Questions on: Miscellaneous
Ron Smith, Horticulturist, NDSU Extension Service
Q: I'm hoping you will take the time to give me some advice on selecting between emerald green arborvitae and juniper skyrocket shrubs. I live in a suburb of Boston and would like to line my driveway with an arborvitae or other decorative shrub. Emerald green arborvitae seems to fit the bill, but juniper skyrocket grows tall and is nice and thin. The reason for the thin choice is so we can see through the shrubs and detect any oncoming traffic when exiting the driveway. We're looking at a possible eight to 10 plants. The emerald green is affordable, but the skyrocket is a little out of price range. Are there benefits to spending the extra money for the skyrocket? Which shrub is easier to prune? (Boston, Mass.)
A: Thanks for a no-brainer! The skyrocket wins hands down. It only gets about 2 to 2.5 feet wide, is moderate in growth, has no particular soil requirements, is tough as nails and is hardy to zone 3. Taking nothing away from the beauty of emerald green arborvitae, it just wouldn't be the best choice for your location.
Q: I have a tree over my garden. Will this affect my cucumbers, tomatoes and zucchini as far as the garden having too much shade? Also, with all this rain we've been getting, is there anything I can do to make sure my plants thrive? (e-mail reference)
A: The shade and roots from an adjacent tree definitely can affect the performance of the vegetable garden. You can have problems with disease, root rot, spindly growth, low fruit set and size. The plants will thrive if you can thin out the tree canopy that is shading your garden. There is no better "thriver" for vegetables than pure sunshine!
Q: Can you provide some advice on controlling tree suckers in my perennial flower beds? I'm constantly fighting tree suckers every year. I've attempted to be diligent and cut the suckers off below the surface, but I can't keep up. Is there something I can apply that will kill these little trees or woody plants and keep them from coming back? (e-mail reference)
A: The stuff I have used is called Sucker Stopper RTU. I have seen it at Cashman Nursery in Bismarck. The sucker is cut off, and then the material is sprayed on. It lasts for one growing season.
Q: I live in northwestern Arkansas and have two crepe myrtle trees. They had just leafed out when a cold blast came through. The temperature fell to 24 degrees one night. The next day, the leaves all shriveled up. Will these survive and still flower or did they die? Can I prune back the dead limbs to help the trees? (e-mail reference)
A: As I have told many before you who have asked the same question, wait until the new growth emerges to see what has been damaged. You then can remove the dead material. These established trees are tough customers. They are able to come back after being dusted with some below-freezing temperatures.
Q: We have two crepe myrtles that we pruned in December. They started to sprout new growth and were doing beautifully until we had four nights of 26-degree temperatures. The new growth turned black and is falling off. Do we need to trim back just below the dead growth or should we leave it alone? I love these trees and don't want to lose them, but I have no idea what to do. Thanks for the help. (e-mail reference)
A: Be patient and wait to see what growth takes place. They probably will recover since they are so mature. The growth might be weird for a while, but they eventually will return to normal. Once the plants have regrown, cut out anything that is dead.
Q: My ladyfinger palm leaves are shriveling up. The plant gets watered every seven to 10 days. Does it want plant food or sunlight? (e-mail reference)
A: Is the palm planted in the landscape or in a container? Are only the oldest leaves showing these symptoms or all of them? A containerized palm will need fertilizing as it starts to show new growth. Since you are asking about the possibility of sunlight being limited, I would say that is the problem. Fertilizing a palm that is getting insufficient sunlight will cause the symptoms you are describing.
Q: Our son built a new home in Blaine (a suburb of Minneapolis). His area requires at least two trees be planted right away. I am guessing he will do more than two at some point. What two great trees should he start with? The house sits north and south on the lot. The lots are large, so the neighbor's trees will not affect his plantings. Thank you. (e-mail reference)
A: I don't like making suggestions because I have no idea what else is planted in the neighborhood or where he is intending to plant them. I also don't know what he wants from the trees, such as amount of shade, flowers/fruit, size, fall color or growth rate. Are there soil problems? This is the kind of stuff that can be sorted out over a few cups of coffee. I suggest he visit some local garden centers because they would stock material that is hardy in the local area. A knowledgeable nursery person could spell out the various aspects of the trees in stock.
Q: The town we live in is graciously giving away trees. Our choices are hackberry, oak, maple, linden, pear, hornbeam or London plain. The trees must be planted on the front lawn. We have a pin oak on our front lawn, but realize it will take some time for this type of tree to mature. Last year it had less than two dozen leaves. We are considering a hackberry because we heard it is quick-growing and drought-tolerant. How long does it take a hackberry to provide shade? Should we consider planting it and then removing it in 10 or so years after our pin oak matures? Should we let both trees grow or forget about planting the hackberry? (e-mail reference)
A: I would stick with oak trees, even if the oak trees being given away are not pin oaks. I'm not in favor of moving trees in the landscape once they have been planted unless it is absolutely necessary. The rate of growth is about the same for all of the species you are being offered.
Q: We recently purchased a home in Sedona, Ariz. We have a plum, apricot and peach tree. During the second week of March, all the trees were in full bloom. By the last week of March, the apricot tree had fruit about the size of a nickel, the plums are the size of peas, but no peaches grew. How long before the fruit ripens? When should I spray the trees and when do they need to be pruned? I am so excited about having fruit trees. Is there a retardant for the deer and rabbits? (e-mail reference)
A: Congratulations on being a fruit tree grower! It is nice to meet someone so enthusiastic about their first crop. I'm going to refer you to the NDSU Extension Service publication on fruit tree culture that you can download. The information is available at http://www.ag.ndsu.edu/pubs/plantsci/hortcrop/h327w.htm. Though this information is intended for North Dakota residents, you can adapt certain parts of it to your climate. For example, dormant oil spraying should be done before the buds open, no matter where you live. Pruning is best done during spring dormancy. Fruit trees often are oversexed, which means the trees sometimes bear too much fruit for the tree to mature. If that happens, Mother Nature takes corrective action by producing a heavy fruit drop about two to three weeks after blossom drop. You can assist the peaches and apples by hand picking some of the fruit when it is the size of a nickel. The remaining fruit then has a chance to grow to full size. As for spraying, you can apply Sevin insecticide right now and again in about two weeks. The insecticide will be broken down by the time you are ready to harvest fruit. As for repellents, some products that are available, include Plantskydd, Liquid Fence and a product appropriately called Deer Away. We have had the best luck with Plantskydd for repelling the widest range of wild beasts and for lasting the longest.
Q: A friend brought me a handful of almond blossoms. We put them in a vase with water and put them in a sunny window. The blossoms are now growing leaves! Can I use these as starts for new plants? I cannot see any roots growing from the ends of the cuttings. Can I put them in rooting material? (e-mail reference)
A: Unfortunately, almond branches do not lend themselves to propagation through cutting. They are grown from seedlings. Trees with desirable characteristics are grafted onto year-old stock. The leafing you witnessed is normal, but lends nothing to the branch's ability to form roots. Sorry!
Q: Am I better off to prune a limb that is partially budding at the trunk or out at the point where the limb is brittle? Will the tree sprout a new limb at the trunk or will the branch continue growing if I cut the limb where the buds stop growing? (e-mail reference)
A: Dead wood is dead and no amount of pruning will revive it. If you prune a live branch back to the trunk, you may or may not get a new branch at that point. Willows are loaded with latent bud and root initials under the bark, which gives them the advantage of being extremely easy to root and form new branches. If you cut back to a visible live bud and remove the dead tissue, that bud will break dormancy and grow as a dominant bud. In reality, as your tree matures, you will be spending a significant amount of time walking around the tree picking up the self-pruning it will produce. Your future pruning tasks will be to keep it in some semblance of shape to enhance your property.
Q: Do you know of anyone who has been able to grow a redbud tree in southeastern North Dakota? Even though we are zone 3 to 4, could one survive in a protected microclimate? (e-mail reference)
A: I don't blame you because they are beautiful trees! However, I don't know of anyone who has grown one successfully. With global warming taking place, it may be possible to have these become a part of our tree inventory in the state, so I encourage you to give it a try!
A: There are just two trees that I am aware of that would meet your needs. The two are black walnut trees, Juglans nigra and possibly Juglans cinerea. I don't know of any nut producing shrubs that would be hardy in your area.
Q: I need help or some suggestions on what to plant. We have about 80 feet of ground. Last year we planted a row of amur maples that we got from our Soil Conservation District. The maples were more in tree form than shrub. We also would like to plant a row of something behind them to help hide a bad grove of old trees. I don't want huge trees. I was thinking cotoneaster, but the gal at the office in Forman said I can't do that if I have any apple trees in my yard. Aren’t they more disease-resistant now? The apple trees are quite a distance from this row of trees. Any help or suggestions from you would be greatly appreciated. I live near Milnor. (e-mail reference)
A: Apples and cotoneaster are in the same family (rose). In spite of the distance, unless it is in miles, the trees would be prone to passing disease organisms back and forth. This could obliterate one or the other, if not both, or force you to do a lot of spraying. Did you ask about common lilacs? They get about 15 to 18 feet tall and spread almost as much. If they are not to your liking, how about planting nannyberry viburnums? They have attractive flowers, foliage and edible fruit for wildlife. They also are good, tough, dependable plants.
Q: Would it adversely affect my trees (apple, maples and ash) to prune them at this time or should I wait until March? (Erskine, Minn.)
A: Pruning at this time will not hurt the trees.
Q: Our Cub Scouts sold Christmas trees this season. There are a lot of pine needles that they didn't shake off before shipping. Can I use the needles as mulch or are there spores on them that could affect my plants and trees? The trees came from Oregon, if that makes a difference. (e-mail reference)
A: The needle trash can be used as mulch around your landscape plants. There is no more risk in using these needles than there would be from using needles from your own property.
Q: I have potted tangerine and tangelo plants I keep in the house during the winter, but set outside in the summer. The plants were repotted into larger pots last summer and moved inside before the first frost. The tangerine started losing its leaves and was bare by Dec. 1, but had two tangerines on it. Now, the tangelo is dropping its leaves. Is this normal for these citrus trees? I also have seed from my gladiolas from last year that I did not plant last spring because it was too dry and hot. Would this seed grow if I planted it next spring? (Egeland, N.D.)
A: Leaf drop of citrus trees moved inside for the winter is common, but usually not lethal to the plants. It is caused by a dramatic shift in the plant's environment. The plant moves from high light intensities, long days and high summer temperatures to an environment with low light, short days and modest temperatures. Continued normal care should have them releafing in a few weeks. Don't overwater or fertilize in the meantime. I don’t know if the gladiolas seeds will grow, but it certainly is worth a try!
Q: We have a lot of brush and trees to clean out of our grove. What's the best way to keep whatever stumps are left from regrowing? Is there a certain time of year that is best to do this? We'd like to do it during the winter. (e-mail reference)
A: Winter is the best time to begin the attack because you will not be fighting insects and you can get into the site (generally) and see what you are doing much better than at other times! As spring comes, there will a flush of growth that can be treated with a brush herbicide or a strong dose (according to label directions) of Trimec or Glyphosate (Roundup). You will get kill-back and most likely regrowth, which you should attack again. Depending on the species and their vigor at the time of removal, a couple of applications or more through the summer may be needed.
Q: I would like to know if the Saskatoon berry bush is the same as a Juneberry bush. If there is a difference, I would like to know the size of the bush and fruit. Is there more than one type of Juneberry? (Rugby, N.D.)
A: They are the same. There are at least six to eight Juneberry cultivars.
Q: As a Hortiscope fan, I thought I might ask you what I can do with a date palm. I love the dried fruit during the winter. I never thought that the handful of pits I tossed into a planter would sprout, but they did! There are four spears standing anywhere from 4 inches to 16 inches tall. Who knows, maybe more will sprout! I tossed the pits into the planter thinking they might compost and help the rather poor soil. The spears appear healthy and vigorous. I hate the thought of destroying anything tough enough to sprout like this. I'd appreciate any advice you can provide. (Ashton, S.D.)
A: Having spent almost three years in Saudi Arabia, I am well aware of the toughness of the date palm! Move the plants to a sunny location and augment the weakening sunlight with a strong plant light. If you can, keep the temperature to at least 72 degrees in that area. Date palms like and thrive in heat and desertlike conditions. They are oasis trees, so don't be too short on the water.
Q: I would like some advice about what kind of trees we should plant on our property. We have had to take out many old elm and ash trees. We have come to appreciate the box elders. Does anyone plant them anymore? Last fall we planted two oak trees. They are doing well, but it seems wise to plant another variety. Native trees make sense, but we'd be open to other varieties that would do well. Thanks. I always read your columns and appreciate your advice. (e-mail reference)
A: You can go to an excellent site posted by Todd Weinmann, Cass County horticulturist, at www.ext.nodak.edu/county/cass/horticulture/treeshrub/decidtrees.htm for a snapshot of many trees, along with basic information about each species. You also can go to the Tree Information Handbook at www.ag.ndsu.edu/trees/ to check out the comments made by the authors on even more trees. This manual was edited by some of the state's top horticulturists who have an interest in trees. Enjoy and thanks for making contact!
Q: My honey locust is looking somewhat sick. It was covered with heavy ice for several months last winter. Right now, it looks spindly and has more pronounced leaves at the ends of the branches. I have deep-watered it several times this summer, but I am sure it was not overwatered. Will it recover? (Kent, Minn.)
A: From your description, I doubt it. Consider replacing it this autumn with a more robust tree.
Q: We are considering planting a privacy screen between our lot and the neighbor’s. We have a sizeable lot. Can you give us some ideas on what trees to plant? We have no height restrictions where we live. We want trees that are disease resistant, hardy and do not send up suckers. (Lisbon, N.D.)
A: This is something that you will have to do. All I can do is give you guidelines, which can be found at www.ext.nodak.edu/extnews/askext/treeshr/1411.htm. Then go to www.ext.nodak.edu/extnews/hortiscope/tree/treecntnts.htm for a listing of tree species. Click on a species name for more information. That way you will be able to make educated decisions about what it is you can plant, but are not limited to my biases or preferences. Everybody views trees and privacy screens differently, so it is a personal choice. Two of the most notorious species for suckering are cottonwood and cherry or plum. The Cass County Extension horticulturist has a very nice listing of trees with photos at www.ext.nodak.edu/county/cass/horticulture/treeshrub/decidtrees.htm.
Q: I have several volunteer trees on my land (cottonwood, ash, elm and hackberry). I would like to transplant them to another area to keep them growing. Can you tell me how and when to do this? (e-mail reference)
A: Do it this fall after the leaves have dropped or early next spring before they leaf out. Dig as much of the root up as possible and then plant immediately at the same depth.
Q: Do you have any suggestions for a fast-growing, disease-resistant, shade tree to plant in West Fargo? (e-mail reference)
A: How about elms? Washington, discovery, new horizon, cathedral and vanguard are all disease resistant. You could plant silver cloud, autumn spire, northfire or firedance maple trees. The freeman maple is a hybrid of the red and silver maple using the blended good qualities of both species.
Q: The leaves on my trees have green bumps with brown spots and the leaves are curling. Is it too late to do any spraying? Should I do something next spring? Will it harm the trees because this has been going on for a number of years? Thank you for your time. I look forward to your column every week. (Valley City, N.D.)
A: The green bumps are from midges stinging the foliage in the early spring as the leaves begin unfolding. The brown spots and curling leaves are likely the result of anthracnose or late-spring frost damage. Next spring, while the trees are still dormant, spray them with horticultural oil and lime sulfur at the same time. The dormant oil will help control the insect pests and the lime sulfur may take care of the fungus disease on the leaves. Spray with a Funginex or Bordeaux mixture when the leaves unfold. Thanks for the nice comments about the column!
Q: The leaves on several of my trees are falling off. It seems like there are webs on them, with little aphids or bugs. What can I use to spray the trees? Are they in danger of dying? (Binford, N.D.)
A: It is doubtful that your trees will expire from this one-time defoliation, but the problem should not go unattended. Based on your description, I cannot tell what the insect is that is doing the feeding. I suggest you obtain a broad-spectrum insecticide, such as Sevin, that is approved for garden or fruit tree use. It should control the problem. Next spring, before leafing out takes place, spray the trees with dormant oil to kill off overwintering eggs and cocoons.
Q: The bark is coming off my honey locust tree. The tree seems to be rotting and has small holes in it. There are some ants on it by the holes. Can you tell me what’s wrong and what I should do? (e-mail reference)
A: It doesn't sound good. The problem could be bark beetles or borers. You have to make a judgment call to decide if the tree is worth trying to save. Use Advanced Tree and Shrub Insect Control (Merit) as a drench around the base of the tree. The product is taken up and translocated systemically through the tree's vascular system to get an effective kill. There is a chance the tree may recover after using the product. Be sure to follow label directions.
Q: I'm working with new fruit trees that aren’t doing well. The trees are apple, crabapple, plum and cherry. The trees were planted a few years ago and had recycled rubber mulch mats placed around them. The trees also were getting a lot of water through drip irrigation. Based on advice, we pulled up the mats because they were covering the grafts and discontinued the drip irrigation. This spring all the trees leafed out some, so I thought we were on our way to recovery. Now it seems ants have stripped off the leaves on two trees. Is there any hope for these trees? (e-mail reference)
A: Yes, there is hope, but get rid of the ants. This is the first time I have heard of ants stripping the leaves off fruit trees. Go to a garden center and purchase some ant poison to distribute around the base of the trees. The trees should releaf again.
Q: I read about rust galls in your column. You mentioned that they were devastating to hosts, such as apples and Hawthorns. Do the galls have to come in contact with these trees to do harm? We have a new snowbird Hawthorn growing about 6 to 8 feet away from our low-lying juniper and a neighbor’s apple tree just across the driveway. Do you think we need to remove the rust galls? Also, will the galls affect an upright juniper? (e-mail reference)
A: Galls will use a juniper as an alternate host without causing any significant damage. Pick off the larger galls on the juniper and dispose of them. This interrupts their life cycle and protects trees, such as apples and hawthorns, from the more devastating form of the rust fungus.
Q: I have extremely hard water. I’ve heard that when watering my trees and shrubs, I should never get the leaves wet. Is this true? (e-mail reference)
A: Hard water will leave a deposit that is unsightly, but not lethal to the plant. If built up too much, the deposits can inhibit photosynthesis, which may result in plant stress or growth reduction. Other than that, watering outdoor plants with hard water should not be a problem.
Q: After the snow storm we had at the end of April, a lot of trees were left with broken branches. Should something be put on the wounds to prevent insects and diseases? Also, I have a tree shelterbelt. I’m having problems with the spruce trees. I had the soil tested and everything checked out OK. Some of the trees grow to a certain height and then topple over. Years ago there was a pig barn near the site. Could it be that the runoff from the barn has affected the soil? It seems to me that when the tree gets older and the roots reach a certain depth, something is getting to them. (Bowman, N.D.)
A: You do not need to put anything on the tree wounds. The trees should heal on their own, but be sure to make the proper cuts back to the trunk. The spruce trees may have a disease. Check the needles for spores. You may have to look at the needles under a microscope. If the trees are Colorado blue spruce, they are very susceptible to disease.
Q: I read that you have suggested getting a certified arborist from the International Society of Arboriculture to get rid of quaking Aspen. I had some people come last year and take out six of my quaking Aspen. Yesterday, I went out to work in that area and removed the ground cloth. Under the cloth, I found many Aspen roots. Most of the roots were 1 to 1 1/2 inches thick. It was like a nightmare. I only worked in a small section, but my back is hurting and I really didn't accomplish much. I need help getting rid of it. Can a regular landscaper do the job? Would using Trimec work for me? Is it found in local nurseries? I have another quick question. My dad read something about growing tomato plants upside down. I tried it, but the plant didn't thrive and quickly dried out. Any suggestions on what I did wrong? (e-mail reference)
A: Yes to your questions. Trimec will kill the roots when applied to the suckers. Hire a landscaping company to remove those roots. They usually have crews of young people whose backs are more nimble than anyone older than 40 and can get the job done quickly. There is a gimmick unit that you can purchase somewhere to grow tomatoes upside down, but why in blue blazes would anyone want to do that? Save your money and grow them the conventional way and enjoy their goodness.
Q: For our bushes, my husband wants to buy wood chips and tree shreds from a company that cuts down trees and use the materials as mulch. We would put down a plastic weed guard for control and then cover it with the mixture of wood chips. The company has free delivery. Any problem with this plan? (e-mail reference)
A: If I was the company, I also would deliver at no cost! You are saving them disposal charges, but you will benefit, too. Keep in mind that you don't want to lay plastic for weed control. Buy a woven geotextile material that will allow air and water to penetrate. Keep the mulch layer no thicker than 2 to 3 inches. If you go thicker, you begin running into anaerobic problems in the root zone. Keep an eye on the plants because uncomposted wood chips tend to tie up available nitrogen to the plants. If at all possible, try to compost the chips for three to four months before applying. This is to get the internal temperature up to pasteurization levels that will kill most harmful organisms (insects and diseases).
Q: I have a Madagascar dragon palm that is 8 feet tall. I am running out of places to put it because it is so tall. Can I cut the top back? Will it branch out again? Any suggestions would be greatly appreciated. Thanks for your help. (e-mail reference)
A: You can and you also can do an air-layer on the part of the palm you cut off and then plant it. Go to www.ext.nodak.edu/extpubs/plantsci/landscap/h1257.pdf and download a copy of my publication, "Home Propagation Techniques.”
Q: I am writing this e-mail in hopes you can help me save my May Day tree. I live in Alaska. The tree is in the backyard and gets morning sun. It is a fairly young tree, but it is reaching the top window of my two-story house. Two years ago, I noticed that the bark of the tree was split from the grass line to about halfway up. I tried putting tree wrap around it to keep the bark in place. After a number of months, I took the wrap off and noticed that the bark had curled, leaving more than half of the inner tree exposed. That exposed part had slugs and spiders on it that I removed. The exposed spot is now black with some white areas. It managed to survive another harsh winter and has buds on it. I really like this tree and I don’t want to lose it. Is there something I can do for it or am I eventually going to end up losing it? (e-mail reference)
A: You did the right thing by removing the wrap and keeping the exposed area clean. The tree will work on healing itself during the growing season. Don't paint it or add any unneeded fertilizer. It should be OK because May Day trees are pretty tough. We have them in North Dakota as well.
Q: I have an individual interested in utilizing tree tubes to enhance growth and exclude rabbits and deer. I know that the tubes do enhance growth, but what is the impact on the roots? Are the roots able to sustain the added growth? Do you know a source for tubes? (e-mail reference)
A: It would be better to use a repellent, such as Hinder or Plantskydd. Both work great and are a lot less expensive than the tubes.
Q: We are going to do a tree planting for a new park in Wahpeton and were given a list of trees to choose from. The list includes patmore and summit ash, Dakota birch, red splendor, spring snow, snowdrift, Indian magic and pink spire crabs, little leaf linden and autumn blaze, sienna, embers and crimson king maples. Any suggestions or other tree choices that you could provide would be appreciated. (e-mail reference)
A: You are somewhat heavy in the crabapple department. I would suggest also considering northern acclaim honeylocust, prairie torch buckeye, pekin lilac, snow mantle dogwood, prairie reflection Laurel willow and prairie statesman Swiss stone pine. My suggestions are all introductions from NDSU's Dale Herman. These trees have gone through rigorous testing and evaluation for many years. You can be assured of their hardiness and disease and insect resistance.
Q: Can I use Canadian cherry wood for smoking meats? (e-mail reference)
A: I don't think so because all parts of the plant, exclusive of the fruit, are considered toxic because it contains HCN (hydrogen cyanide). I have to add that I am not an expert on the choice of wood for smoking meat, but from what I know of this species, I wouldn't do it. I have asked Julie Garden-Robinson, a nutritionist at NDSU, for her interpretation of your question. Agree or disagree, she will get back to you with the official take on this. In the meantime, don't experiment!
Q: I am planning a “living wall” around a large residential subdivision in Moorhead, Minn. The purpose of the plantings is to create a natural barrier to traffic noise and adjacent developments (replacing typical cedar fences). We tentatively are planning on planting approximately 400 Colorado blue spruce, 250 maples and 350 miscellaneous shrubs. I have heard concerns regarding Colorado blue spruce diseases, but have found they are much less expensive than similar species. I would appreciate any advice about our plant species selection. Also, I would appreciate advice on how far apart we should plant the trees, while still allowing the living wall to be an effective barrier. (e-mail reference)
A: Go to my Web site at www.ext.nodak.edu/extpubs/trees.htm and then scroll down to publications EC 1764 and EC 1767. The publications discuss windbreak plantings in detail. The information should be applicable to what your intentions are. If you have any questions after looking over the publications, get back to me.
Q: I am new to North Dakota. I have been trying to find trees that I can plant that grow fast and will be an excellent windbreak. I moved here from a state where fences are all that you see, so I do not want to put up a snow fence. I am on a lot next to a highway and will appreciate the privacy. (e-mail reference)
A: Welcome to North Dakota! It is always great to greet a newcomer. Of course, I am delighted to help you. Go to the NDSU Web site at www.ext.nodak.edu/extpubs/trees.htm for publications dealing with windbreak establishment and care.
Q: I am having a difficult time planting lemon trees. I have taken the seeds and put them in containers filled with warm water to help with germination. After less than 24 hours, I took the seeds out of the water containers and then scattered and buried the seeds into a rich, dark soil. It has been a little less than a month and still no sign of growth. (e-mail reference)
A: It could be the fruit was irradiated to slow spoilage or that the fruit was harvested when it was immature, so the seeds will not germinate. Normally, citrus seed is quick to germinate. You should see results in a few days to two weeks. You might want to check with the source to see if the fruits were irradiated anywhere along the way from harvest to retail sale.
Q: We recently moved and since then our staggered Madagascar tree has lost its leaves. It has three stems. The one without leaves has a stem that seems to be drying out. I have had this plant for 17 months and would hate to lose it. I have tried placing it in different rooms, giving it Miracle-Gro and repotting it. The leaves on the other branches are a light green instead of a darker green. This plant has changed dramatically since we have moved. Is there a way to save this plant? (e-mail reference)
A: Here are the requirements for this species. First, it is a false palm, meaning that it characteristically has a whorl of foliage on top of a bare stem. Yellowing of the older foliage is natural as the tree ages. The plant also needs to have the soil kept moist, but the amount of water should be reduced by probably 50 percent during the winter months. Speaking of winter, while the dragon tree can tolerate cool temperatures, it cannot go below 55 degrees or else problems will occur. Finally, it needs good indirect light, but not direct sunlight. This would mean putting it in an east-facing window, just outside the impact of direct sunlight. If you follow these basic recommendations, I think your tree will recover.
Q: I have a landowner who has a newly planted one-row shelterbelt of flame willow trees. The trees are showing signs of having a high pH level (yellowing and smaller leaves). He would like to neutralize the soil. What would you recommend to amend the soil to lower the pH? (e-mail reference)
A: I promise you it would be an act of futility. Lowering the pH level in highly alkaline soils is like attempting to empty Lake Superior with a coffee cup! The soil should be tested for pH, N,P, K, soluble salts and possibly the iron and sulfur content. Deficiencies in nitrogen, iron or sulfur can cause the symptoms you describe. It would be easier to nail down the deficient element through testing. If it turns out to be a microelement, corrections can be made by adding chelated forms to the soil.
A: This sounds like a spider mite problem. Washing the foliage is the correct thing to do. You also might want to try misting the plant on a regular basis. Mist the tree two to three times a week to keep the mites under control. Mites often show up in large numbers on some houseplants during the winter months because of the dry, indoor air from central-heating systems.
Q: We purchased a potted Norfolk pine from a department store for our Christmas tree because we have a small child and cats that surely would have knocked over a larger tree. Within a week, the pine started drying and browning. I paid careful attention to its watering by waiting for the top inch or two to dry before watering again. It was away from heat vents and next to a south window. I took off all the decorations and gave it a heavy pruning, ridding it of the dried branches. If nothing else, it will look green for a couple more weeks. There's not a whole lot left, just the main shoots and leaders. Is there anything I can do or is it going through an acclimation period? Is the southern exposure too much? Did it get too shocked when brought outside from the store to our house? The temperature was in the teens. (e-mail reference)
A: You could have problems if the tree was not double-wrapped before leaving the store or it wasn't placed in a prewarmed car. All it takes is about 40 seconds of exposure to temperatures in the teens to cause the problems you describe. The tree never will recover the lateral branches that have been lost. You might as well throw the plant away. Pick up a new tree this summer when transporting it from store to vehicle and vehicle to house is not a threat to the well-being of the plant.
Q: I purchased a Madagascar palm last summer. It has been doing great. Now that it is winter, half of its leaves on one side have fallen off. I keep it indoors. I water it when the soil is completely dry (two to three times a month). The trunk was silverlike when I got it, but the top part is still green. Is it supposed to do this? Are the leaves going to grow back? Am I doing something wrong? What can I do to help it? (e-mail reference)
A: This species is as tough as it is ugly in my opinion. It will recover the foliage when you set it outside this spring. I view growing Madagascar palms like raising piranhas in a swimming pool. You eventually will live to regret it. I'll give you three to four years of moving it in and out of doors without body armor. If you don't use armor, you may want to notify the local blood bank when you are planning to move it. This is a tough, xericlike plant, so keep it on the dry side. You are providing the right cultural care for it. If you get around to repotting, make sure it is in a porous clay pot.
Q: I haven’t seen your question-and-answer column in any of the local newspapers for some time, but I assume that you are still in business. I am inquiring about two species of nut trees I have long been interested in. I am enclosing an old issue of the Raintree catalog. In my opinion, it is one of the best and most reliable nurseries. It offers the Turkish tree hazel and seedling plants of the American chestnut. Both of these are listed as Zone 3 hardy. What do you know about these two nut species? Are they reasonably hardy in sheltered areas of this region? If so, can you tell me about their planting requirements? I know that the bush hazelnut grows in northern parts of North Dakota and in Minnesota. (Turtle Lake, N.D.)
A: Thank you for your support! Whether a paper publishes the column is up to it. I supply the column to whoever wants to use it. Both species of woody plants would be marginally hardy in North Dakota. My texts list them as hardy in Zone 4, being killed back when temperatures reach minus 30 degrees. My experience with both species dates back to my time in Ohio, where they thrived. To try them out in North Dakota is a gamble, but where would humankind be today if limits were not pushed?
Q: I have Norway pines lining my driveway. It has been my experience that when I trim a branch, the entire branch will die. I need to trim these pines, but I don't want all the branches to die. Is there something I can do to keep the branches from dying? (e-mail reference)
A: With pines, it is all in the timing. Trim in the spring as the "candle" growth emerges and before the new needles completely unfold. This is what is trimmed or cut back. If you cut back farther, as you have found out, the branches usually die. As most pines mature, they tend to lose lower branches to expose the trunk. If these are the branches you have trimmed, console yourself to the fact that they would eventually die and fall off anyway. Go to www.ext.nodak.edu/extpubs/plantsci/trees/h1036w.htm for additional information on pruning.
Q: I happened upon your Web site and am wondering if you could tell me how to transplant my staghorn. It weighs about 250 pounds. The basket I started it in is rusty and basically gone. I don't want to hurt it. (e-mail reference)
A: My advice? Don't touch it! Contract out the project to someone who would know how to handle such a monster. If it is still doing OK without the basket, why mess with it?
Q: This summer we had a destructive windstorm that came through, took several of our older evergreen tops off and uprooted numerous green ashes. I am wondering what the fate of these evergreens will be. The wind also sheared many needles off. We are going to move some green ash trees from our shelterbelt. What is a good time of the year to move them and how large can the trunk be? I am also thinking of moving some variegated dogwood shrubs. Will I be successful? Lastly, what can I do about creeping Charlie? My lawn is full of it! (Esmond, N.D.)
A: The evergreens probably will be all right, just misshapen. The best time to move any woody plant material is early spring, while the plant is still dormant. This includes green ash and dogwoods. Smaller stock always has a better chance of surviving a move than larger stock. If given a choice, go smaller rather than larger. If the creeping Charlie is growing in dense shade from trees, I would suggest allowing it to stay as your ground cover. If it is growing in open turf, then apply Trimec in early September to bring it under control. It will take repeat applications and the material stays soil active, which means it could migrate to the tree roots, causing some decline, and eventually even death. If the weed is everywhere, then an application of Roundup is suggested where everything in the lawn is killed. You then can replant with the appropriate grass seed.
Q: Can you use pine cones for mulch? I have many spruce trees in my yard that produce pine cones. I would like to use the cones for mulch around my maple trees. My husband says the cones are too acidic. Since our soil is so alkaline, I think it would be OK. What do you say? (Dickinson, N.D.)
A: Cones from spruce or pine trees can be used as mulch without harm. If the cones come from spruce trees, they are spruce cones, not pine cones. It’s a common mistake many folks make because we often think of pine cones as a generic term. Just don’t overdo the mulch. Some people get too carried away when they start adding organic mulch, thinking that if a little is good, much more would be better.
Q: My sister-in-law is allergic to weed whackers (her words, not mine). She uses Roundp around the trees in her yard instead of trimming with a weed whacker or push mower. I accidentally sprayed the bottom of a tree with Roundup, but nothing happened because the leaves were not touched. Can my sister-in-law be doing long-term damage to her trees by using Roundup? They’re full-grown trees, which are mostly spruce, oak and fruit trees. In addition, do you remember me writing to you about my raccoon problems and telling you that zucchini worked for keeping them out of the sweet corn? Well, I’m told by a reliable source that buttercup squash is the best for that kind of raccoon defense. The vines must be pricklier. Also, we’ve had some grub worms in the yard and the raccoons (or maybe skunks) have been turning the sod on my lawn upside down looking for them. Sometimes in the morning, my yard looks like a war zone. Maybe I’ll put the whole yard into buttercup squash next year! (Kindred, N.D.)
A: Your sister-in-law is on safe ground spraying Roundup around the base of the trees. In fact, in the long-term, it is likely better for the trees because string trimmers are responsible for canker development and mowers inevitably are bumped into the trees, scarring the bark and leading to decline. Once the Roundup hits the soil, it is deactivated. It only works on green tissue.
Q: We cut down four poplar trees last fall. Within the last three to four weeks, we’re being inundated with runners from (we think) these trees all over our yard. We are planning to have the stumps removed soon, hoping that will help, but is there something we can spray to kill the runners? Any solution you may offer will be appreciated. (Fargo, N.D.)
A: Let me use this as a lesson for all who read this. If your intent is to remove a tree for any reason, unless it is a hazard, wait until it leafs out completely in the late spring and then flowers. Then remove the tree. Most of the energy to produce suckers will have been spent in this surge of growth and reproductive cycle, so the amount of growth from the remaining roots will be minimal. To control the problem you are having, treat them like weeds and spray with Trimec. The Trimec will get translocated into the roots and provide an effective kill. Don’t expect it to work with just one application. You should succeed with two or three applications. If you apply it now, in midsummer, do so again in the early part of September on the regrowth that shows up then.
Q: We recently planted a hawthorn tree. It was healthy when we bought it, but now it has developed orange spots on many of its leaves. What is this and what can we do? (Jamestown, N.D.)
A: The orange spots are probably cedar-apple rust. There isn’t a lot you can do this year except clean up the fallen foliage. Next spring, before new growth emerges, spray the tree with lime-sulfur. During the pink bud stage, spray with something containing zineb or ferbam. Spray again at petal drop with the same material. Funginex or a Bordeaux mixture also will give you some control.
Q: We have been searching the Internet to see if a Norfork pine can be topped off. Is this possible? (e-mail reference)
A: You bet. The best way to top it off is by air layering. That way you get another plant to work with. Go to my Web site on home propagation techniques for a complete description of the procedure. The address is
www.ext.nodak.edu/extpubs/plantsci/landscap/h1257w.htm. Have fun!
Q: I have mushrooms all over my backyard. At first, a couple of years ago, they were in a small patch under an old tree stump. Now they are spreading everywhere. I have used some chemical applications, such as Trimec (when I was spraying the creeping jenny). Someone told me to sprinkle soap powder on the mushrooms, but that didn’t help. (Starkweather, N.D.)
A: You can do little about mushrooms. They are visible responses to the decay of the tree roots taking place in your soil. The only alternative is to dig everything up and get all the rotting roots out of the ground, which not too many people choose to do. They are not hurting anything and usually disappear or are reduced with warmer, dry weather. Once the decay is complete, the mushrooms will cease.
Q: I have a Norfolk Island pine that has started losing its branches and is turning a pale color. I have added Miracle-Gro and put it under some trees to keep it out of the sun. I am afraid I am going to lose the tree, which was given to me by a good friend. What can I do to prevent more damage? (e-mail reference)
A: Norfolk Island pines are fussy about being moved, so this is a common problem. It sounds like you have done all you can to help, so now the waiting begins. If it continues to decline, do an air-layer on the top 12 inches of the plant. That will at least keep the plant alive, but smaller, and will give the pine a chance to adapt to your home environment.
Q: I have a client who is planning to plant a few horse chestnut trees this spring. He has heard that the leaves and the chestnuts are poisonous. Do you know if that’s true? (e-mail reference)
A: Horse chestnuts are poisonous and are not dependably hardy to North Dakota. Your client probably is talking about the Ohio Buckeye chestnut. Ohio Buckeye is toxic to horses, but can be grown in most parts of North Dakota.
Q: How long should wood chips be aged before using as mulch? (e-mail reference)
A: I would like to see it go for a season or six months, if possible.
Q: Our city has a tree and limb dump. The city chips the limbs and stockpiles the chips. The sources of the limbs and the species from which they derive could be from healthy or possibly diseased trees. The chips are available for the taking by anyone who wants them. Is there any reason that these chips should not be used to mulch around mature trees and in flower gardens? If so, what restraints should one exercise? (Madison, S.D.)
A: This is done all the time around the country. I would hope that any Dutch elm-diseased trees would be debarked or at least separated into burn piles. Generally, nothing adverse comes from using this mulch around the base of mature or otherwise healthy trees. It is the start of a slow composting practice of sorts.
Q: We had two arborvitae and juniper bushes on each side of our front door. Now, just the stumps are left. How can we get rid of the stumps without using a grinder? (e-mail reference)
A: Use the time-honored method that I still depend on - digging them out with backbreaking labor! If this is too much for you, get a high school football player to come over and give him a few bucks to do the work. Have him wield a mattock, a sharpshooter spade and possibly a pruning saw to chop, dig and prune the remains out. You also can use saltpeter that is available at most garden supply stores. It is sold as “Stump Remover.” It slowly works on the stump, getting it out over a period of several years. I prefer the first method, then it is over and done.
Q: We have a well for our water supply. A few years back we installed a water softener. How harmful is softened water on outdoor plants and trees? That is my only source of water other than trying to catch rainwater! (Mayville, N.D.)
A: Did you install the softener or did a contractor do it? In most cases, the companies that install water softeners do not channel the softened water to the cold-water line, just the hot. If you did it yourself and it is connected to both lines, then the softened water eventually will harm your plants. The sodium from the salts will set up a reaction in the soil that will cause it to lose structure over time. The sodium also is toxic to plant growth as the concentration increases.
Q: I have a staghorn sumac that is sending shoots out in many places. Can I dig these up and replant them in other places? I don’t want any more in the area where the main tree is located. If these shoots can be replanted, what’s the best way to do it? (e-mail reference)
A: Replant as early in the season as possible and with as much of the root as possible. Give them a good soaking after replanting and water them enough to keep them from wilting.
Q: I look forward to reading your column each week and really appreciate your timely and pertinent advice. I have a question about mulching and soil additives. There are so many different products on the market. I don’t know enough about mulch or additives to make an educated purchase (which may explain why the success rate isn’t great)! Can you explain the reason for the differences and suggest applications? (Buchanan, N.D.)
A: The use of mulch is based on aesthetic preferences because all the organic mulches have the same purpose. Basically, the shredded mulches stay in place better than the nuggets. Nuggets tend to blown away or wash off during slightly severe wind and rain events. To be effective as a weed barrier, the amount of mulch needed is in the range of 3 to 4 inches, with 4 inches being better. The organic matter slowly breaks down, adding nutrients to the soil and root zone and improves soil tilth. Unmilled sphagnum peat moss is best suited for use as a soil conditioner because it improves the structure of heavy clay and sandy soils. It has the added benefit of being weed-free and tends to lower the pH to more acidic levels with continued use. I don’t think there is such a thing as adding too much peat moss to garden soil. With peat moss, the trick is to be thorough in mixing it into the soil or root zone profile. Thank you for the nice compliment about the column. It is great having you as a faithful reader!
Q: I’m having a bit of a problem with my Madagascar palm. I understood the leaves would fall off during the winter, so I was looking forward to new growth in the spring. When March hit, new fronds started growing, but then they started to shrivel. I’m terribly sad about it. What’s going on? (e-mail reference)
A: This is an indication of too much salt, fertilizer, water or poor drainage. Another possibility is that the plant was moved to an area where heat or cold drafts hit the foliage directly.
Q: What is mulch and where can I get some? (e-mail reference)
A: Mulch is usually organic material, such as shredded bark, bark chips, peat moss or weathered compost. You can get mulch at almost any store that sells garden supplies. Keep it away from the trunk of the plant to prevent disease problems.
Q: I was hoping you could help me out with a decision. I hope to relandscape my yard this spring, so I need to choose a tree to plant in my front yard. Right now, there is a diseased European mountain ash and a dying spruce in the front yard. I want to get rid of both and plant a new tree. I’d like a smaller sized tree similar to the mountain ash. I’d also prefer a tree that will attract birds. I was thinking of a chokecherry, until I saw that they probably will become diseased. I thought of a small variety of birch, but since my two neighbors already have these trees in their front yard, I want to do something different. I have a newly planted maple tree on the berm, so I hope to avoid doubling up on that. Do you have any recommendation for another tree that fits that size, fares well in a North Dakota winter, is generally hardy and has a decent chance of avoiding disease? (e-mail reference)
A: Consider planting a Japanese tree lilac (Syringa reticulate) or an amur chokecherry (Prunus maackii). Both are cold hardy and tolerant of North Dakota weather conditions. Given good drainage, they will reward the owner with outstanding beauty.
Q: I will be helping my kids landscape a yard on Elmwood Avenue in Fargo. The homes in the area are small and close together. The kids would like a couple of trees between them and the neighboring house. What type of tree would have more upright growth without spreading a lot? Your advice column is the first thing I read every Friday. Keep up the great work! (Maddock, N.D.)
A: The Lombardy poplar often is used for that purpose, but it is such a sorry excuse for a tree that I should have my mouth washed out for even mentioning it! One of my favorite trees from when I was living in Ohio is the spring snow crabapple. It is more oval than upright, has nice white flowers in the spring, but no messy fruit. It is hardy to Fargo, with an eventual height of 20 or more feet and a spread of about 12 to 15 feet. If you want to experiment, try the fastigiata ginkgo tree. This is an excellent choice if horizontal space is limited. I don’t know what the eventual horizontal spread is, but this is a fruitless male clone. The reason I say experimental is because it is not “officially hardy” in our state, but there are several growing in and around the city. You probably will have to go to a nursery in South Dakota or the Twin Cities to obtain it. A very hardy plant introduced by our own Dale Herman here at NDSU is the prairie spire. It is rapid growing and narrow pyramidal in form. Thank you for the very kind comments about the column. It is supported by good questions from people like you!
Q: I purchased a majesty palm about two weeks ago. I have noticed some yellowing and tip burn on some of the lower leaves. I also see three new shoots growing. I would like to know how to care for this as a houseplant (many have told me it can’t be done). I mist it twice a day, water it two or three times a week and have a vaporizer in the room for humidity. It sits in a west-facing window. Can the palm be placed outside when the weather permits? (e-mail reference)
A: You are overwatering your palm. Lower your watering rate to once a week or less. Go to my Web site on houseplant care at www.ext.nodak.edu/extpubs/plantsci/landscap/h1123w.htm. You will find loads of information on the site that should help you. Yes, you can summer it outdoors.
Q: We heat our home with wood and have a lot of ashes. What are some good uses for the ashes? We were putting them on the garden, but I think it has changed the pH in the soil too much. Can we put the ashes around our blue spruce trees? (e-mail reference)
A: Wood ashes are high in pH values and potash, which can be leached through rainwater. If you live in a high acid soil region, that actually would be beneficial. If the soil is alkaline, above pH 7, then problems could exist. In that case, I would incorporate the ashes into composting material so the alkalinity of the material can be reduced. Some application around a spruce would not hurt anything if the above situation applied. However, continuous applications could lead to some problems, such as a tie-up of the metallic trace elements.
Q: I would like to propagate a large number of caragana trees from cuttings. What method should I use? In addition, is it possible to propagate Russian olive trees? (e-mail reference)
A: With caragana, cuttings taken in May and June will root at an 80 percent rate if treated with a rooting hormone. Russian olive trees do not root well. Seeding is the preferred method of propagation. Stratify the seed for 60 to 90 days at about 40 degrees.
Q: Recently, I had a conversation with a horticulturist and Kansas State forester regarding the quality of deciduous shade trees available at nurseries, garden centers and discount stores. The horticulturist/forester made the statement that the quality issue is one of container-grown trees versus containerized trees. At the time, that statement went over my head at Mach 3 speed. Today, I realize that his statement was probably quite profound. Could you elaborate on the quality difference between the two? (e-mail reference)
A: Container-grown trees have their entire root system within because they have been grown in containers (imagine that!) since their seedling days. Containerized trees are trees that may have been grown in a nursery field (balled and burlaped). The burlap or the ball breaks down and the tree or shrub is then containerized. Any roots that can’t fit in the container are removed. The same is true with field-grown woody plants. If the difference isn’t too much, then it is no big deal. If there is nothing left but the fleshy or prop roots, it is a big deal because that plant’s ability to take up water and nutrients is greatly impaired.
Container-grown and containerized woody plants are easier to handle, ship and care for by retail outlets, making them the logical choice for all retailers. This saves labor, is cleaner for the client to handle, and most members of the human race know enough to take them out of their containers before planting into the landscape. At that time, it becomes immediately evident as to whether or not the plant was container-grown or containerized. With the former, there should be roots beginning to encircle the interior geometry of the container and the rootball (soil and roots) should hold together fairly well. With the latter, there will be no such encirclement and the rootball will fall apart, exposing the stubby roots that were cut back. Many nurseries get bare-root plants for early season (while the plants are still dormant) sale in this very competitive market. Savvy gardeners know this is the best time to make economical, quality purchases. Rose bushes, raspberries and small fruit trees (called liners) are examples. As soon as the plants begin coming out of dormancy, the nursery operator has two choices: heel them in or plant them in containers. In this instance, if the right size container is selected, quality potting soil used, the planting is successfully carried out and no problem exists, you can have a good container-grown plant. This is because from that time on, that is where the plant will remain, in a container. The plant will be moved up to the next nominal size pot if needed. Essentially, the retail outlets, usually family-owned businesses, do the same thing that wholesale nurseries would do; move the small bare-root stock into containers for the duration of their life before being planted. Without a doubt, the quality will be with the container-grown stock rather than the containerized material.
Q: You mentioned in your column that saltpeter could be used to get of rid of stumps or that saltpeter would help. Where can I buy saltpeter? We would like to use it on some stumps we have. (Fargo, N.D.)
A: The material may not be sold as saltpeter (potassium nitrate) anymore. Look for stump remover products that list saltpeter as a major ingredient.
Q: I have a question about digging or grinding stumps. My builder says that if I grind the stump down, the rest will rot over time and leave soft spots in my yard. He says if they are big enough, the ground will sink. He says if I dig up the stumps using a backhoe, I can fill in the area with dirt and prevent any soft spots. (e-mail reference)
A: If the stumps are ground down, the sawdust removed, the hole filled with suitable soil and packed down in a suitable manner, you will not have a problem. It is done thousands of times a day around the country. The backhoe can remove the stumps, too, and the same operation carried out. Neither action will get all of the roots out. When the roots eventually do rot, the decay provides nutrients for the living plant material and shouldn’t leave any depressions or soft spots of any consequence. If there are roots left in the soil the size of a Volkswagen, it could cause a problem or two, but normally not. The decision is yours to make. I hold an International Arborist Association (ISA) certification and he is a builder. I don’t give advice on building homes, just plant material. You really have nothing to lose with either plan, if done properly and completely.
Q: I have a friend who is clearing my lot. He will take the trees, but leave the stumps. What is the best way to get rid of the stumps? Should I dig them up or grind them down? (e-mail reference)
A: If you have ever dug out a stump, you wouldn’t be asking the question! Grinding the stumps is by far the easier of the two methods. The machine is easily maneuvered into place. Grind the stump and adjacent roots to sawdust. Scoop up the sawdust, let it compost and then use it as mulch or burn it. Digging out tree stumps, even small ones, always seem to have a “surprise” root waiting for me to find before I can get it out. Digging is the way to go if you want a good workout, but be sure you are in good shape and on good terms with a local chiropractor!
Q: I read your garden tips article every week and really like it, but I was a little confused about one of your answers. Someone had removed several cottonwood trees that were next to electrical boxes. The tree service would not grind the stumps. In your answer, along with using Sucker Stopper and Salt Peter, you advised renting a stump grinder. I must have missed something. I can’t think of anything more dangerous than a stump grinder in the hands of an amateur, especially around electrical wires. (Fargo, N.D.)
A: You are right, but I believe the question referred to electrical boxes on poles, not in the ground. I would hope the individual would have the common sense to realize that it would be tempting death if the electrical boxes were in the ground. Thanks for being a faithful reader of the column!
Q: We live in zone 4 and are considering planting peach trees, which are rated for zones 4-8. I’m also considering planting valiant grapes, which is a South Dakota State University variety suitable for zones 3-8 and blueberries rated for zones 3-8. Will these fruit trees survive and bear fruit if taken care of properly? (Ashley, N.D.)
A: Valiant grapes should be a piece of cake. The blueberries will need 100 percent sphagnum peat moss and winter protection. Planting peach trees is a coin toss. Plant the peach trees where there is protection from spring winds and cold air drainage. Grow them hard not soft. This simply means not over-fertilizing the trees or allowing any turfgrass fertilizer to reach the tree’s roots. Nothing ventured, nothing gained, so go for it! Nothing beats a tree-ripened peach unless it is freshly harvested raspberries!
Q: Is south Moorhead in zone 3 or 4? I have heard both from different sources. (e-mail reference)
A: Take your pick as to hardiness zones. You are in zone 4 if you live south of the interstate highway. Those living north of the interstate are in zone 3. If you believe that, I have a bridge I want to sell you. In reality, you can get a lot of zone 4 plants to survive our fickle weather with good cultural practices. The same applies to zone 3 plants. Most of the time plants in either zone expire because of our freeze/thaw cycles that often begin in late February and continue through March and sometimes into April, and not from our coldest temperature in midwinter. That’s why using good cultural practices is important.
Q: I’ve got some trees/shrubs that are starting to look bad. You often advise people to contact a certified arborist (I think that’s the term you use). How do I find one? (Fargo, N.D.)
A: I have direct experience with two people in Fargo. Kelly Melquist, (701) 729-6899, is very good at diagnosing tree problems and finding a possible solution. James Danielson, Cougar Tree Care, has the uncanny ability to remove limbs or entire trees with the competency of a surgeon. Danielson can be reached at (701) 729-7208.
Q: We live along the Sheyenne River. This spring we had clay fill brought in and this fall we would like to have some spruce trees transplanted and maybe some pine trees. Do spruce and pine trees do well in clay/sandy loam soil? Also, we have a shelterbelt composed of cottonwood, ash and dogwood trees. We had black fabric put down, but now I hear that isn’t good for the trees. I’m willing to take it out if it is going to harm the trees. We have had problems with the fabric blowing in the wind and rubbing against the trees. Is it wise to buy trees now and plant them or should we wait until spring? (e-mail reference)
A: I haven’t seen where spruce does not do well! They are extremely adaptable to all types of soil and drainage situations. Pines are a little more sensitive to poor drainage. This is an excellent time of year to purchase containerized nursery stock. The sooner the better as far as planting goes. The roots will actively grow while the soil temperature remains above 40 degrees.
Q: We have several very old and tall burr oaks in our yard. We have a few mushroom-looking fungi that have started protruding out of the bark on one side of the trees. The fungi is whitish, hard and rubbery feeling. There are several woodpecker holes that have fungi growing out of it this year. The bark where the peck holes are is very loose and the wood underneath is soft and has ant tunnels. There is a hole close to the peck holes that you can look into and see another fungi growing inside. On the opposite side of the tree from the peck holes is another small fungi. We are concerned that this fungi has gone through the center of the tree. Can we scrape off the bark that is loose and spray that area with a fungicide? If we were to do that would new bark grow? Can you give us any idea what these fungi are called and why we would have them? (e-mail reference)
A: Get the tree professionally removed very soon! The growths you see are a physical manifestation of decay taking place internally. The woodpecker holes are an indication that borers or bark beetles have found the tree to be tasty. Once these growths called conks are witnessed, it is a sign of advanced internal decay. Your tree is doomed, so don’t let it take you or any part of your property too.
Q: I have a doublewide home on a large corner lot. I planted evergreens on the north side for wind protection. There is a small maple tree at the northwest corner. I would like to plant two or three shade trees on the west (back) side. What would you suggest and how far apart should they be planted? (Watertown, S.D.)
A: Go to a local nursery and see what they have for selections. Make your decision based on that. Some of the more dependable shade trees for our area are hackberry, green ash, lindens, black walnuts (if you don’t mind the nuts), bur oaks and cultivars of silver maples.
Q: I planted an Aspen this year. Some of the leaves are turning black and shriveling. Others just have a few black areas. Should I spray the tree with anything? (e-mail reference)
A: It sounds like the tree has come with its own built-in disease problems! I would get a refund and start over because it isn't going to get better.
Q: I had several trees removed and the stumps grinded down. I also spread top soil over the entire lawn and re-seeded. The lawn looks great with the exception of the areas where trees were removed. There is a light yellow circle at each spot. The circle is slightly larger than the tree. (e-mail reference)
A: The yellow circle is an indication of nitrogen tie-up from the stump sawdust and root grinding that took place. It can easily be corrected by applying a high nitrogen fertilizer. You might want to apply it to the entire lawn to get everything a nice even green color. As the sawdust ages, the problem will disappear.
Q: I would like to try to fashion a fence-like structure, training the branches of three trees. Is it harmful to trim unwanted branches throughout the year? Am I able to somehow top the tree to keep it around 8 to10 feet? I know this is usually done with dwarf trees, but these were freebies, and I don't have a lot of room? (e-mail reference)
A: Yes to both of your questions. Keep the tree growing in two dimensions - vertical and horizontal against the wall or structure. This is not a difficult task, just one that needs regular attention.
Q: What types of trees do you suggest we plant on a piece of land we acquired in Otter Tail County Minn.? We hit water about 14 to 16 inches down when we dug a hole in the back of our property (this week). It is about 36 inches from the water table in the front of our property. In the middle of our property we have a stand of old-growth basswoods. We were thinking of river birch in the back part of our property or some kind of willow, but I personally think willows are too messy. Highway 78 runs right behind our property so we would like some kind of barrier from the noise. (e-mail reference)
A: Go for the linden if you already have one on your property. You might want to contact the Otter Tail County Master Gardeners for some help. They are a gung-ho bunch of devotees that love to assist in garden/landscape undertakings. Contact the County Extension Office.
Q: How close to a well system can I safely plant a tree? The tree I'm considering is an American linden. (Harvey, N.D.)
A: A well system should not be a problem to any great extent. Wells are enclosed unless they are hand-dug, which I haven't seen in more than four decades! A linden will probably do fine if it is planted anywhere from 30-50 feet away, assuming your concern is the root system.
Q: We are moving to a location that does not have trees. What is the fastest growing shade tree? (Pelican Rapids, Minn.)
A: The fastest growing trees in this area are hybrid and other poplars. Your local nursery should have a good idea about what is available. Fast-growing also usually means short-lived. For example, the Lombardy poplar (a variety from Europe) grows very fast and straight and then dies in about 20 to 25 years. At that point, you're stuck with a tall (40 to 50 feet) dead tree in your yard that needs to be removed. If it is not close to anything such as a house or powerline, then it is easy to cut down. If there are obstructions, it will be difficult and expensive to remove. Remember this when you are determining plant locations. Having said that, I still think hybrid poplars are great for a quick, temporary shelter. You may want to consider planting poplars in combination with other trees that are slower-growing. The poplars will provide quick shelter while the other trees get established. Think of poplars as disposable.
Q: We planted a row of cottonwoods and a row of blue spruce trees at one end of what was once a cattle barnyard. The area has been planted to crops for the past 20 years. The land must be quite fertile because the crops were heavy and tended to lodge. The trees were planted about five years ago. Each year we had to replace some of the blue spruce. Some of the damage is by deer and a hail storm we had, but some of the trees do not seem to be able to survive no matter what care we give them. The trees get yellow and dry up. It has been suggested that perhaps the soil is too fertile. If this is the case, what trees would you recommend to replace them? (Valley City, N.D.)
A: This is a common problem with areas that have been cattle feedlots. Trees simply don't do well in these areas. No one is sure of the exact cause, but it seems that excess nitrogen (as nitrate) in the soil is common. As you said, the crops that are grown in this area seem to grow well, but lodging can be a problem if there is too much nitrogen in the soil. A second idea that comes to mind is using a herbicide called Casoron. This is a pre-emergent herbicide used for control of perennial weeds such as Canada thistle or leafy spurge. For whatever reason, spruce trees are very sensitive to this herbicide. It causes the needles to turn a bright yellow and fall off. The trees eventually lose all their needles and die. There is not a whole lot you can do if you have a nitrate problem. Most trees won't survive. If Casoron is your problem, you have a lot of options. Most other trees or shrubs do not have a problem with this herbicide.
Q: Have you heard of royal paulownia trees? Will they grow in North Dakota and what is their life span? Will planting them be something I will regret in five to10 years? (E-mail reference)
A: Thank goodness royal paulownia trees are not hardy to our area. They are extremely messy and require a lot of maintenance. They do grow fast. If you ever want to see them, visit Longwood Gardens in Delaware. You will see the best of this species, if they still have them.
Q: I am planting a 100-foot row of emerald green arborvitae. I am having a retaining wall built and these will be planted about two feet away from the top edge of the wall. The wall will have a drainage system behind it. Do you see any placement issues? (E-mail reference)
A: I would recommend placing the plants a little further back from the top of the wall. These plants don't have invasive roots, but they will follow the flow of water to the drainage system. This could cause a minor problem down the road as the roots develop and concentrate in that area. Enough pressure could develop and cause the wall to buckle at those points of contact. You could also solve the problem by having a root barrier installed.
Q: I have a question about Juneberry trees that are grown and established. They have not produced fruit in the last three or four years. The trees blossom and then produce a few berries, but they do not mature. Could it be an insect or fungus causing the problem? (Williston, N.D.)
A: It is more likely frost damage than an insect or disease problem, as either of those two would be rather obvious. I have occasionally had the same problem with my Juneberries only to have them come back like gangbusters the following year! Your problem may be an incomplete or non-fertilization of the flowers.
Q: My husband and I recently moved into a new home. We discovered this week, to our disbelief and horror, a young tree that was planted with the plastic bucket still around it. It is budding right now. We believe it's a silver maple. My husband and I dug around the pot and cut away as much plastic as we could. We had to leave almost half on the bottom because I couldn't get to it without the risk of severing the primary root. I carefully filled in the soil around the tree and then watered. Will it survive? Is there anything special we should do to help it? (Jamestown, N.D.)
A: As incredible as your message is to read, it is unfortunately not uncommon. Hopefully, your efforts will help the tree survive. About the only thing I can think of are the girdling roots. You didn't mention if you cut through those. If you didn't, make some clean cuts with a hand pruner or a sharp knife as soon as possible. Do this in at least two places opposite each other and, if possible, a third spot between the two. You have done all you can to help the tree survive. Don't allow it to become drought stressed, but don't overwater it either. Good luck!
Q: In a recent article you recommended using Bravo for needle cast. Can I assume that this refers to spruce trees and that this is the best product? Also, is there any problem with applying Bravo to all my spruce even though some are less affected or not at all? (Fargo, N.D.)
A: No problem with a universal application of Bravo. Apply it in early June and again in early July.
Q: Is there a local arborist I can call? I live 20 miles south of Fargo? (E-mail reference)
A: Try calling Kelly Melquist at (701) 729-6899 or James Danielson at (701) 729-7208. Both have done excellent work for me and get my highest recommendation.
Q: What fungicide do you suggest for rhizosphaera needle cast? What are some appropriate suggestions on application, timing, etc? (Linton, N.D.)
A: Rhizosphaera needle cast, assuming the plant isn't too far gone, is best controlled with a product known as Bravo, which can be applied during the late spring or early summer months. Follow the directions on the label. It will probably have to be applied for two or three years in a row to bring it under complete control.
Q: I have three rows of trees approximately 120 feet long. One row has common lilacs that are spaced five feet apart. The other two rows are green ashes that are spaced eight to 10 feet apart. Each row is spaced 18 feet apart. I would like to install a drip irrigation system this spring to reduce the time it takes to water. I have 60 pounds per square inch on a 3/4-inch water supply line. I would like to know what size water line and emitters I should use. (Bismarck, N.D.)
A: You didn't say if the supply line is copper, PVC or polyethylene. Without that answer, I am going to make some assumptions. The flow capacity is 10 gallons per minute or 600 gallons per hour, which is the figure you would be interested in using. The lilac row would have 24 plants spaced five feet apart. The ash rows would each have 12 plants, spaced 10 feet apart. The total number of plants being irrigated would be 48 with each requiring three point source emitters at two gallons per hour for a total of six gallons per hour delivered to each tree. Six gallons per hour time’s 48 trees equals 288 gallons per hour required at the source. You have plenty of leeway in your supply line with 312 gallons per hour left over for future expansion if needed. Sixty pounds per square inch is too high. It would blow the emitters out of the polyethylene line. You need a pressure-reducing valve at the header line to bring the pounds per square inch down to about 15 to 20. You should install a filter at the header to prevent the emitters from clogging. You didn't say what type of soil you have. I’m going to assume you have a loam and not sand or clay. Run the system for two hours and then shut it off. Check how much of the soil ball is wet. It should be wet beyond the roots of the plants. If it isn’t, run it another hour or so until that happens. That then becomes your watering time. You could use 3/4-inch polyethylene line for each row and essentially lose nothing to pressure friction. Run the lines down the tree rows and get a multi-outlet emitter (pressure compensating) and some micro-tubing to insert into the outlets. Bring each one up to the edge of the rootball, spacing them evenly around each plant. Anchor them in some way to keep them from being blown around by the wind. Be sure the bug caps are installed over the end of the emitter tubing or else all kinds of stuff will crawl in. Give the system about three years to establish the plants. Move the emitters out a little farther each year to expand the root system.
Q: I noticed the question about growing pecans in North Dakota. I found a hardy variety in the Miller Nurseries catalog. It says this winter-hardy pecan will tolerate 30 below temperatures and it lists zones 4-9, which is almost the same as their hickory, which is a zone 4-8 and a black walnut, which is zone 5-9. (E-mail reference)
A: Let me know what kind of results you have. It would be great if you succeed because I'd love to see pecans growing as a dependable nut crop in our zone. Pecans taste good and are healthy for you.
Q: I noticed in this week's edition of Hortiscope that someone from Napoleon asked about growing pecans. I thought I remembered seeing a variety that was fairly hardy in one of my catalogs. I did find it in the Miller's Nurseries catalog out of Canadaigua, N.Y. It says this winter-hardy pecan will tolerate 30 below temperatures. It shows that the variety will grow in zones four through nine. I have ordered fruit trees from this company and they have good quality trees. (E-mail reference)
A: Go for it and let me know what kind of results you have. It would be great if you succeed because I'd love to see pecans growing in our region as a dependable nut crop. Pecans are tasty and healthy.
Q: I’m hoping you can answer a question I have regarding a contorted filbert tree I purchased last year. When I bought it, the nursery provided some pruning instructions on specific ways to keep the branches contorted. The instructions stated that if you pruned the tree improperly the branches would no longer contort. Any advice or instructions you could provide me would be greatly appreciated as I do not want to loose the contorted look this tree has. (E-mail reference)
A: The contortions of the tree are lost when the tree is over-pruned back to beyond the graft, which would be difficult to do since the graft is on the rootstock of the species. What they might have meant is that if you prune more than 25 to 30 percent of the tree at any one time, you might cause extensive suckering to develop from that rootstock. If unchecked, it would wipe out the grafted scion wood that is doing the contorting. You might be lucky and have one of the cultivars that are propagated via stooling, a process that has the roots developing on the contorted stock rather than having it grafted.
Q: Can pecans be grown in south central North Dakota? Is if feasible to grow it in the house? Are hickory or walnuts an option? (Napoleon, N.D.)
A: Pecans (Carya illinoinensis) are not even marginally hardy in our area. Even if it were, this tree along with other members of the hickory family develops very significant taproots that make it difficult if not impossible to transplant. A homeowner is better off obtaining the fruit and sowing it directly where the trees are desired, taking into account the mature size they will eventually attain. Both the hickory and black walnut are or should be available from the Soil Conservation Service and will grow in most areas. Often, the SCS will come out with seedlings and plant them for the property owner if they are used for conservation purposes. These would be bare-root, probably one-year old stock that would be planted while dormant in the early spring. Otherwise, nurseries and garden centers may carry them as container-grown trees that an individual can handle as a specimen tree.
Q: I have a question about my rubber tree. I’ve had it for more than a year. It sat by a west window and grew rapidly with good colors and was very strong. I recently replanted it to a larger pot and moved it about 10 feet back. It is not happy. It stopped growing and several leaves turned orange then fell off. It is my understanding that they are very diverse in their surroundings. I thought the move would be hard but the plant would recover. It isn't. What do you suggest? (E-mail reference)
A: What you have done is to change the light dynamics of the plant. Also, you didn't state why you repotted it, which is generally not done at this time of year. Repotting should take in early fall or spring. If you can, move the plant closer to the window or get some plant lights that shine directly on the foliage. It will not correct the discolored leaves currently on the plant but will encourage new growth that will be strong and healthy. Keep the lights on for at least 12 hours a day.
Q: I would like to know if the hull of a hazelnut is useful for domestic animal feeding. (E-mail reference)
A: I checked with some of my colleagues in animal and range sciences and they have no information on it. Sorry I cannot help you but I imagine that there must be some value to them. Perhaps someone reading this will know and get back to me.
Q: I have started a tree farm and one tree species I have planted is aspen. I ordered trees from Baileys and Lawyers ranging in size from 1 to 2 1/2 feet. I also have some 5-foot trees. They are all growing well but they have larger leaves (that do not tremble) than the natives in the Black Hills and they do not get the fall gold color. They turn an ugly brown and drop off. My customers will not buy the tree once I tell them that they may not have the gold color in the fall. Why don’t they get the good fall color this species is known for? (Sturgis, S.D.)
A: Because you were sold something other than the quaking or trembling aspen species. Insist on botanical names from nurseries. Populus tremuloides is the quaking aspen that gets the yellow fall color on the leaves.
Q: I have a young redbud tree that my neighbor would like to plant a seedling from. There are many smaller trees growing up around it, so I said he could have one. He says it’s okay to plant in late fall or early winter but I've always heard spring was the best time. (E-mail reference)
A: It depends on where you live and the size of the transplant. Early spring might be better, if you live in a region of extreme cold and exposure. Otherwise, fall would work because there is not as much demand on the top part of the plant and the roots would have time to get established before the ground freezes.
Q: Is it possible to raise Frasier firs in northeast S.D.? (Sioux Falls, S.D.)
A: Yes, as it is in zone 4, which is the high end of this plant's hardiness zone. I will be very jealous if you succeed because they are one of my favorite trees! It would need supplemental irrigation and spraying of the foliage during hot, dry periods in summer, which shouldn't be a problem. But watch out, they develop into beautiful Christmas trees so people have been known to steal them right off the stump. Some way to celebrate Christmas -- presents under a pirated tree!
Q: We've had a rubber plant tree for almost 10 years that we’ve kept in the house. The last two years we've put it out on the deck in June. It has thrived with new leaves and grown 2 to 3 feet but it lost almost all of its leaves after a hard frost last week. Can it be saved if we bring it inside? (Brookings County, S.D.)
A: Bring it inside and give it plenty of water and light. It will eventually re-leaf.
Q: I am in the process of developing several 4- to 5-acre shrub plantings for wildlife. The shrubs I am using come from a list by the N.D. Game and Fish Department. The list includes chokecherry, silver buffaloberry, silverberry, American plum, Arnold's hawthorn, snowberry, red osier dogwood, skunkbush suma, woods rose and Juneberry. Is it possible or practical to grow any of these plants from seed? I would like to try it on a limited basis. It would be fun to have some plants propagated from seed and would give me some personal satisfaction. I've planted about 5,000 so far and am planning on another 15,000 to 20,000 over the next 10 years. (Robinson, N.D.)
A: Yes, it is possible to grow each one from seed. I suggest getting a hold of a book on plant propagation or Dirr's book, Manual of Woody Plants. In it he mentions the best methods for propagating each of the species, either by seed, cuttings, division, or other methods.
Q: I have a very old juneberry tree whose leaves are turning yellowish brown and falling off. The tree is almost bare and it is only mid-August. Also, the trunk is a little greenish in color. I’m hoping you can tell me if this tree is diseased or dying. (E-mail reference)
A: Obviously so but I cannot tell you what could be doing it from your description. Since it is in the same family as the apple, I suspect it might have a leaf spot or scab disease that commonly afflicts apples. About all you can do at this point is clean up all fallen litter and starting next spring, spray the shrub with lime sulfur while still dormant. Follow up with a spraying of Bordeaux mixture after leafing out is complete. That may stop the development of the disease.
Q: I have decorative retaining blocks I put around my trees and filled with decorative mulch. I have a ton of grass growing up through it. What can I use to kill the grass but not my tree? (E-mail reference)
A: Roundup is the best way to go. It will kill the grass and other green stuff but will not harm the tree as long as you do not spray the foliage.
Q: I have a 5-year-old hawthorn. This year, three quarters of the bark has come off the trunk and the leaves are very small. Can this tree be saved? (E-mail reference)
A: It doesn't sound like it. Once the damage is that extensive, it is usually only a question of time before the tree dies.
Q: This spring I planted a row of seven poplar trees, a row of 35 Lilacs, a row of 15 sumac and a grouping of three red maples. All of the plants came from our county Soil Conservation Service. I've made about 20-24 inch diameter rings to hold mulch out of thick plastic edging for each tree or bush. They all seem to be doing very well. I’m almost finished putting plastic and rock on top of each row to prevent any grass or weed growth in between the trees. I mulched heavily inside each ring with cypress mulch and water thoroughly once a week if we don't get rain. The trees and the landscaping all look great but are there any problems that the plastic and rock could cause? Is there anything else I should do to keep them healthy? (Lisbon, N.D.)
A: It sounds to me like you’ve given the project a lot of thought and done a lot of work to get these plants established. If you haven't overdone the mulch around the plants (greater than four inches), they should be ok. It certainly will not be your fault if they don't turn out beautifully!
Q: I would like to know where I can order or purchase some buds or plants to start a diamond willow patch? I'm buying five acres of land and thought it would be neat to try and grow some diamond willows. I want to make canes or other stuff out of the willows. (Williston, N.D.)
A: I am glad you asked the question because the subject has just about driven me nuts over the years. Here is the best explanation I can give you based on my most current knowledge. There is a diamond willow species and a diamond willow fungus. It is the fungus, not the species that produces the dark, artistic cankers used to make colorful canes and walking sticks as well as other decorative home furnishings such as lamps and candleholders. Diamond willow, the species, is Salix eriocephaia, or the synonym Salix missouriensis. To add to the confusion, Salix pulcha has the common name of diamond leaf willow. The diamond willow cankers are produced by fungus acting on various species of willow trees and not by the diamond willow species itself. I do not know where you can get the diamond willow species if that is still what you want. At least you now have the proper names to do some searching.
Q: I have a small tract of land with three rows of trees on it. The rows are on a hill following directly down the hill. They consist of lilac, ash and caragana. They are about five years old and are five to 12 feet tall. When we till or cultivate, the water has a nice furrow to run down the hill so we are losing a lot of top soil. Do you have any suggestions? Should we plant grass or something else? On this same tract of land, we want to plant more trees but on the other side of the hill. We want to avoid erosion problems and keep native grasses growing. Can we plant trees without cultivating and tilling the ground? When we've done this, we ended up with nothing but weeds and lost all the good native ground cover. The tract of land is about five acres. Our goal is to have a grove of trees with fruit trees and the like inside. We don't have resources such as water and power to groom it daily. We have a water tank on an old truck. (Dickinson, N.D.)
A: You need to plant grass between the rows. I suggest a creeping red fescue like Cindy or Ruby. They are easily established, help to control weeds and will do well in the shade. I would treat the other land the same way. Kill everything with Roundup, mow down the dead growth, inter-plant your trees, then seed with the red fescue. You could use sheep fescue in place of the red. It will get about six feet tall and stop growing.
Q: This is the second year I’ve had my honey locust. The trunk and limbs appear green yet there are no buds. Is it just too early or is my tree "toast?" It gets plenty of water, probably too much. I don't know what to do about that because the sprinkler system controls the amount. It’s either the grass or the tree. I have removed all the mulch that was under the tree. It has pretty good run-off and is in the open on the west side of my deck. (E-mail reference)
A: It is a little early to give up on the tree. The irrigation system can be adjusted so that the system comes on just before the grass shows symptoms of wilting. Most lawns are watered too often anyway. I’ve had an irrigation system in my yard for 17 years and I find that, if I manually control the cycling, my lawn, trees and water bill are far more attractive to me!
Q: I’m looking for any ideas regarding the planting of trees in my front yard which faces directly west. We do not have air conditioning so by late afternoon during the summer it is hotter in my house than it is outside. I need something that grows fast, is easy to mow around and is full of leaves to block the sun. I was thinking a laurel leaf willow but any other suggestion would be greatly appreciated. (Saskatchewan, Canada)
A: Poplars will grow the fastest, but you would not be thanking me for the suggestion a few years from now! One of my favorite trees is the linden. It seems to have everything going for it: dense foliage, relatively fast growth, attractive flowers in summer, and in some cases, a halfway decent fall color. A cultivar to look for in your region is harvest gold which was introduced in your country. American linden cultivars include frontyard which grows to 70 feet tall and sentry which gets to approximately 60 feet tall. A little leaf linden cultivar is norlin which was introduced in Manitoba by the Jefferies nursery. The best thing to do is visit local nurseries and see what the nursery owner recommends. Often advice from a distance can miss the mark completely so I like to make suggestions and follow it up by encouraging local visits.
Q: We have strange trees growing in our evergreen windbreak. They have black berries but the birds won't eat them. Someone told us they are buckthorns. We have cut out a few of them but, like a bad penny, they keep coming back. I've also heard there is a spike one can buy that will kill a tree. Do you know if there is such a thing, its name and where it can be purchased? (Eagle Bend, Minn.)
A: In Minnesota the buckthorn is considered a noxious weed. The DNR has a program for controlling it. There is also an organization in Minnesota called Trees Trust ( www.treetrust.org ) that can help. Their phone number is (651) 644-5800. They will give you a prescription process to follow in order to get rid of this pest.
Q: The leaves on my indoor yucca tree are very dusty. The dust sticks to the leaves and I can't get it all off with plain water. I know there are commercial plant-leaf cleaners that I can buy but is there a home concoction that I can make that will safely clean the leaves? (E-mail reference)
A: I would suggest using insecticidal soap. It will not hurt your plant or you and it should clean it up quite nicely while getting rid of any hiding varmints that may be lurking in the leaf axils thinking they had found their nirvana!
Q: I’m looking for the address of a New York state tree and fruit tree nursery. I don't know the name of the mail-order business. The nursery specializes in zone 2 and 3 hardy stock. They carry many wild shrubs and native berry trees. They also list heritage apple and pear trees. (Thief River Falls, Minn.)
A: I know exactly the nursery you are talking about. It’s the St. Lawrence Nurseries in Potsdam, N.Y. All of their products are organically grown, hardened off and not pushed for size with high nitrogen fertilizers.
There are a number of ways you can reach Bill and Diana MacKentley.
- Phone: 315-265-6739
- Email: firstname.lastname@example.org
- Surface mail:
St. Lawrence Nurseries
325 State Hwy. 345
Potsdam, NY 13676
If you call and reach Bill, watch out, this man will talk your ears off about plants!
Q: We received a mailer advertising a particular tree that sounds too good to be true. According to the ad, the paulownia tomentosa grows to roof height in one year and grows to 40-50 feet high in subsequent years. It supposedly grows in almost any soil and is hardy to -30 F. What is the life expectancy of a tree that grows that rapidly? How about disease resistance or ability to tolerate strong winds? We have a 3-year-old house in Burleigh county on two acres of land. The wind blows incessantly and the sandy soil makes it difficult to grow trees. We and our neighbors have our lots outlined in lilacs and/or dogwood, but they are still only 3-4 feet high. I have two apple trees and two silver maples planted in our yard for shade and wind reduction. The trees are approximately 8-10 feet high. Would it be practical to plant a couple of pawlonias to get immediate shade and hope they die by the time our other trees mature? Tree placement is limited because of our septic system and I don't want to have these trees compete too closely with the maples near the house. There is plenty of room on the upwind side of the lot where the paulownias would actually shade the maples as well as the garden from the late afternoon sun. Is there another tree that you would recommend for a windbreak or fast shade? I understand that cottonwoods and poplars are outlawed by our local housing association. What about Chinese elm, or terragana ? (Bismarck, N.D.)
A: The "miracle princess tree" is making its way into the market once again! When something sounds too good to be true, it almost always is and the paulownia is no exception. It probably would not survive in the location you describe. It is marginally hardy in zone 5, where it can get protection, and officially hardy in zone 6 or 7. The wood is extremely brittle so it would probably get blown apart during the first summer. If it did survive the summer winds, then our negative temperatures would surely kill it. In short, you wouldn't be happy with it. A similar tree and almost as fast growing is the catalpa. It isn't a beauty, it gets large and has messy "bean pods" but it is hardy and tough enough for most North Dakota conditions. We have one (at least) on the NDSU campus in Fargo and it appears to have weathered the many storms that have hit us over the years without too much trouble. I'd suggest visiting the local nursery and checking out what they have that is tough and fast growing. They may or may not carry the catalpa since it is more of a reclamation type tree and not a beautiful ornamental. As a kid I used to love the tree for the big white blooms and the "super beans" they produced. I won't tell you what we used to do with the seeds.
Q: What is your opinion of boxwoods? I have seen Korean boxwoods available in my area. Do they need to be trimmed and shaped often? What about their hardiness for our area? Also, what do they require for sun exposure? If they are not successful in my area what would be similar to them for a northeast corner of a house? (Onida, S.D.)
A: If you have seen them successfully growing in your area, I would think they are fairly hardy enough to make it. They are the kind of plant that responds well to trimming which should be done on a seasonal basis to maintain optimal looks. They are usually considered a "formal" plant, and no, they do not require full sun exposure. In fact, winter sun causes a winter burn or sun burn on the foliage in many locations, so a northeast exposure would be acceptable. My experience with boxwoods has been limited to Ohio, New York, Pennsylvania, New Jersey and through the south. We cannot successfully grow them in North Dakota.
Q: I found a very unusual tree in my back yard when I moved into my house. A clipping I found in the basement along with some research showed it to be a catalpa tree (cigar tree, also known as a catawba tree). I have since noticed a handful of catalpa trees in the area. However, every one has seed pods. Mine blooms but never produces pods. (For which I am thankful after reading that they can make a mess). Why doesn't mine have pods? Is it a female? Is there anyway to reproduce the tree by seed or another manner? I have never seen the tree offered by any local nursery. I did notice that a nursery in the twin cities offered it, but advertised it as having pods. Is mine a freak? I would like to grow more but without the pods. (Moorhead, Minn.)
A: The catalpa is usually considered too coarse a tree for planting in a refined landscape setting. The wood is extremely resistant to rot while in contact with the soil, hence it's early use as a source for railroad ties. The trees were usually available through mail-order catalogs as "super bean" trees or from soil conservation sources. The wood is brittle, second only to Lombardy poplar in providing kindling. Seed will germinate readily without any pretreatment. As a kid I used to collect the giant pods, pop out the seed and grow them in small pots, most of which died (thank goodness!) but it gave me a confident green thumb. Root cuttings taken in early winter will develop and if yours is truly a non-fruit bearing tree, that is the way it should be propagated. I suspect that you don't have the Catalpa speciosa, instead you probably have the Catalpa bignoniodes. It’s a southern species that is somehow surviving but the sexual parts of the flower are killed off by our capricious weather. All the catalpa species have perfect (male and female parts) flowers. Hope this information helps!
Q: To the lady with the beaver problem. She should us 36 inch hardware cloth, 3/4 to 1 inch, wrapped loosely around the trees so it will expand with the tree. That should save her trees if she doesn't live by running water. They will kill acres of trees if they dam running water. What they eat isn't too bad. In two years she will be glad to get rid of them. The guy that's going to move trees should learn to root prune first so the tree will make a root ball. It sure helps in sand or sandy loam. (Bemidji, MN)
A: Thank you for your common sense advice. I'm sure all of the readers will appreciate it.
Q: Can yews be propagated at this time of year? Do the cuttings require heat? I am also interested in dogwoods. How are they propagated? (E-mail reference)
A: Hardwood cuttings can be taken at this time of year and rooted under lights with bottom heat. Use sterilized sharp sand and dip the cuttings in a rooting hormone. Ditto for dogwoods. Rooting should take place in about six weeks.
Q: I was able to get some helpful information from your Web site about the transplanting of trees. However, I still can't figure out how the root ball is formed properly if I'm dealing with sandy soil. I see where they talk about using a box, but I don't understand if the box or burlap should be placed under the root ball before lifting the tree out of the ground or later. Thanks for any help you can provide. I'm directing a boy scout that is doing this for a project. (E-mail reference)
A: I'll try my best to explain the process to you. First, determine how big a ball you can handle. Then start digging a trench around the tree at that distance, cleanly cutting the roots with your shovel or spade as you encounter them. As you dig, taper the ball so the base is smaller than the top. Once you have gone around the tree, then begin undercutting to make a clean cut of the taproot. Next take the burlap and roll it into a tube shape, sliding one end under the ball with someone helping to tip it away from you. Once you have it under as far as you can on one side, then roll the ball back the opposite way and yank the burlap through. You should have enough burlap to wrap to the top of the ball. You can secure it with cotton twine in a criss-cross fashion along with some large nails to help hold the folds in place. Then roll or lift it out of the hole to the new location.
Q: What books would you recommend when looking for information on trimming, shaping and caring for trees and shrubs in this part of the United States? I would like to give it as a gift.
Also, I have tried raising hibiscus indoors by a south window. The bottom leaves always turn yellow and then fall off. I was told they like even moisture and I shouldn’t let them dry out. No matter what method of watering I try they always lose the bottom leaves. I do fertilize every few weeks with a general fertilizer like Miracle-Gro. (E-mail reference, S.D.)
A: I only know of one bookstore so you will just have to explore on your own what is there, as pruning is both an art and science that is more often learned by the school of hard knocks. A good rule of thumb with any pruning is like in cutting lumber, measure twice, cut once. Try to visualize what the tree or shrub will look like when the branch(es) is removed, and certainly have a mental image of what you want the finished product to look like after you are done pruning, otherwise you'll go too far. The hibiscus would probably benefit from a dormancy period. Allow the plant to dry and drop leaves, keeping it barely moist for about 6 - 8 weeks. Then move it to a warm, bright location with some direct sunlight daily, and begin watering heavier, allowing only the top one-half inch of soil to dry. Fertilize only during active periods of growth.
Q: I was wondering the correct treatment for a 10-year-old tree that had about 10 inches of bark stripped off all the way around the trunk by some children. The tree is a nice straight tree, and don't want to lose it. Should it be wrapped with something, or what, if anything, should be done. (Napoleon, N.D.)
A: The tree should be wrapped at least to get it through the winter. Then next spring, if it leafs out, take some cuttings from the top and do what is known as bridge grafting. Refer to the publication Home Propagation Techniques for details.
Q: What is the best time to prune back a Ninebark? I planted one last year and it has flourished beyond my expectations. Can I contain it's growth to less than the 8-by-8- foot natural growth without jeopardizing the overall appearance? I am in a Zone 5 (possibly 4) area. (Ontario, Canada)
A: Yes, by selectively cutting out the thickest stems, back to the ground, each year. Don't remove more than a third of all the branches.
Q: One of the new trees we planted this spring is really struggling. First, all of its leaves/buds were eaten off by rabbits so we put "sleeves" around it; then the leaves/buds came back and it seemed to be taking hold when all of a sudden the top leaves turned brown and fell off. Then the lower ones started to turn brown and we noticed spider webs inside the sleeve; now its leaves look sick and have holes eaten away. Is it spiders doing that or what? (Buchanan, N.D.)
A: Being hot from working outside, I'll bet you a long, cool drink that the tree has been planted too deep. Try pulling some of the soil from around the base of the tree until you see just the top of the rootball. The spiders are your friends. They are waiting to catch any unwary insects, so let them do their work. I think if I am correct that the tree is planted too deep ( a common problem) you will see a big improvement in the tree next spring. Continue to keep it well wrapped this fall and through the winter.
Q: I would like to know if it is safe to water trees, flowers and lawn with water that contains 500 parts per million (ppm). of sodium in the water. What is the tolerable level in the water, and if this water is continued will it build up in the soil? (Tioga, N.D.)
A: This level -- 500 ppm of sodium -- is well within the acceptable levels for growing turfgrass. When it reaches as high as 2,000 ppm, injury may occur, depending on the soil type, frequency if irrigation, and the relative proportions of calcium and magnesium in the soil. Just make sure that your irrigations are complete -- that is, total wetting of the root zone and a little beyond to prevent accumulation of salts from building up.
Q: We are looking for a tree that provides: good rate of growth, shade for a 1 1/2 story home within a couple of years, a rustle sound in the wind, minimal care, clean droppings, large leaves. And has NO sap dropping, NO seed dropping, NO helicopter leaves, NO cottonwood droppings. What do you think? (Grand Forks, N.D.)
A: There is nothing that meets all of your requirements, that's my first answer. Now, for selections that come close, here they are:
- 'Fallgold' black ash
- 'Skyline' honeylocust
- American hornbeam
- 'Macho' Amur corktree
- 'Prairie Gem' Ussurian pear
- Laurel willow
Have fun shopping!
Q: I have a client who wants to plant some trees near his house. He had some pine and spruce trees planted, and they did not fare well at all. We examined the area and tested the soil. There is very little topsoil (1 or 2 inches, tops), hard sandstone and calcium, and I think it was salty, too. Are there any varieties of trees that may thrive here? It is a hillside, and some Russian olives are doing OK, but are quite short. (Bowman, N.D.)
A: They might try some of the Ponderosa pines or limber pines, both of which are native to your part of the state. High salts are going to have an impact on the growth of all plants, even those that are salt tolerant. You might also consider suggesting the larches. Since they are deciduous in winter, they would be under less stress.
Q: I have what I believe is a lemon tree that was planted by seed from Hawaii. The container that I have it in is 38 inches around the top and 12 inches deep. It stands about 6 feet tall, but the leaves have started curling and falling off. Can you tell me what is wrong with it? If it needs repotting, would Miracle Gro potting mix be good to use? I would like to save this plant if possible. I am sending you leaves so you can see what they look like. (Parshall, N.D.)
A: Your sample does appear to be from a lemon tree, but I do not detect any problems with the leaves you sent in. I suggest the following: Move the plant outdoors for the summer. Cut it back by about 1/3 its volume of branches. Repot using either the Miracle Gro product you mentioned or one of similar quality. Be sure the container is free-draining. Fertilize once a month during the summer.
Q: We are just developing a lake lot on West Battle Lake. One of the basswood trees that we planned to keep has developed problems this spring. This year the tree (about 20 feet tall) developed lots of buds but they have not leafed out. The branches still seem to be alive but we don't know what to do with it. It is located about 10 feet from the shore; the land is very sandy. There is another basswood about 15 feet farther inland that is doing beautifully. Last year the water level was extremely high and I wonder if the roots just have had too much water. Should we cut it down or wait until next spring and see what happens to it? There are other assorted trees closer to the shore, elm, cottonwood, etc. that are doing all right. (E-mail reference)
A: This is a good ecological lesson: the elm and cottonwood will tolerate shifting water table levels much better than basswood trees will. Those that do are known as riparian species. I suggest waiting until next year to see if the tree will recover. If not, take it down.
Q: I purchased an Idaho locust tree. It is about 12 feet tall. Yesterday, a high wind came along and broke the tree in half. The tree had been staked. Is there any way of saving this tree or starting growth from what is left? (E-mail reference)
A: Consider the tree a loss. I am against staking trees for the reason you cited. True, trees will lift in high winds, but they can always be reset. Staking creates a fulcrum that just doesn't give, resulting in what you experienced. Start over -- you'll be a lot happier with the results.
Q: I don't know what the stuff is called that drops from trees as they are leafing out. That stuff remained on a new planting around a farmstead. The trees are dead this year. They are 3 years old. Is there a disease affecting the tree and would it be causing death? (Ellendale, N.D.)
A: That is probably the leaf coverings or flower (bud scales) parts that are dropping off. This is common on poplar species, ash species, etc. and is not a source of problems or disease.
Q: Approximately two years ago we removed a large diseased maple tree from our front yard. Since that time we have had an abundant crop of mushrooms. We have been unable to keep them under control and would welcome any suggestions that you may have. They are affecting the lawn. (Jamestown, N.D.)
A: The presence of mushrooms indicates that nature is working to digest the stump and remaining root system. If this is not acceptable to you, the only alternative I am aware of is to have a tree/stump removal company come in and grind everything down to sawdust and haul it away.
Q: Rhododendron trees are now available in our area. Do you recommend them for outside planting? (Fessenden, N.D.)
A: No, because I have not heard any results of their hardiness. Until I do, and get it confirmed professionally, I'll withhold my recommendations on them.
Q: Can systemic anti-fungal treatment be used for needlecast? If so, what are the products that can be used? (Campbell, Minn.)
A: Unfortunately, there are no systemic fungicides labeled for needlecast. Only chlorothalonil and Bordeaux mixture, which must be applied for two consecutive years, shortly after the new needles have elongated.
Q: I 'm building on a lot with over 25 years of growth and trying to incorporate as much as possible. I have some ash trees worth keeping, yet I may have to raise the grade. How much higher can I raise the soil until it causes the trees harm? At this point they have 10 inches of loam; then they hit clay. (E-mail reference)
A: Any kind of grade change will have an effect on the tree's vitality. With 10 inches covering the roots, the trees will likely die off over the next three to five years, being attacked by secondary pathogens and predators (boring and leaf-chewing insects), along with random die-back of branches. At this point, you need to get involved in vertical mulching with stone all around the drip line and beyond. This may do the trick, or it may not. Radial trenching may also be called for. Both processes are too detailed to explain here, but perhaps a local landscape contractor or arborist can help you. I would encourage you to make contact with a competent individual at your earliest to help you save any trees that are important to you.
A good reference is a booklet, "Tree Preservation During Construction," by Gary Johnson at the University of Minnesota.
Q: Are you familiar with the antidessicant Wilt Pruf (active ingredient 25% pineoleene)? The label says not to use on juniper, cedar or arborvitae. Why? These are the species most in jeopardy. They say to apply in March. I think that's too late for the U.S. Can you enlighten? (Devils Lake, N.D.)
A: Yes, I know the material well. The reason they suggest not using it until March is that is the time the plants are most sensitive to possible foliar desiccation, when the soil is frozen or nearly so and the plant cannot uptake adequate water for the transpiring foliage in the bright late winter/early spring sunlight. The common practice is to apply it in the fall before freeze-up, which is all right, but then 90 to 120 days later the material bas broken down, washed off, or simply degraded, and isn't performing its intended function. The recommendation to not use it on the species they list is because research has shown that the material has a phyto-toxic effect on those conifers under certain conditions. Foliar burning (winter burn) was reduced when the application was made in March when the air temperatures were warmer, but the soil was still frozen or too cold to transport sufficient moisture to the foliage.
Q: I have an opportunity to get a holly tree about 8 feet tall now from my parents’ yard in Maryland. Will it survive in South Dakota? My mother loves it and hates to leave them all behind when they move out to the Dakotas to live with us. This one is the smallest in her yard because it volunteered where it didn’t belong. It has to be removed anyway, so will it make it if I mulch it, fertilize it or do what ever it needs? I know nothing about holly tree care although I do have a green thumb when it comes to gardening. (New Underwood, S.D.)
A: I don't advise it. Hollies are mostly broadleaf evergreens (there are a couple of deciduous species) which do not fare well in our prairie environment. I am afraid your efforts would all be for naught, as there is essentially nothing right for it to survive: minimum temperatures are too low, the soil pH is wrong, and the exposure, along with the wide swings we get in temperature, would likely kill it. However, if it has to be moved anyway, what do you have to lose? Give it a shot. Spray it with Wilt-Pruf first, dig as much of the root ball as you can handle, plant it in modified soil, rich in organic matter like peat moss, and fertilize with acid-forming material that is specific for holly and azalea plants.
Q: One of my dad’s trees has started to crack in the crotch of the tree. He was wondering if he should cut the branch that is making the crack worse or if he should tie something around it to keep the crack from getting any bigger. The tree has slanted to one side so for it to grow straight again I thought he should cut the branch off. I just wanted a second opinion. ( Fargo, N.D.)
A: Thanks for a good question. The answer depends on a number of things: The age, species, and size of the branches in question; whether or not the tree will be badly misshapen as a result of the cut you want to make and whether or not the tree's branches are at a location in the structure of the tree that would allow cabling or bracing. Whatever the choice, something needs to be done so there is no further damage to the tree. If your inclination is to cut off one of the offending branches, I trust your aesthetic judgement and ability to make the proper cut. Whatever you do, don't "tie" anything around any branches or a girdling effect will make everything worse.
Q: I have seen bright red-leafed smaller-sized bushes in the landscaping of new homes in and around the Minneapolis area. They are a deeper red during the summer and a bright red in the fall and are outstanding. What are they and will they grow in North Dakota? (Harvey, N.D.)
A: I think what you are talking about is the purple leafed barberry, which in most cases is actually red, and even redder in the fall of the year. Yes, they will grow in most of North Dakota.
Q: Would it be all right for me to do some major trimming on my Sioux Land trees this fall? They have most of their leaves. I guess our freeze hasn't been hard enough for them to drop. (E-mail reference)
A: Late winter, the beginning of March, would be a better time. The wounds from pruning would not heal in time if done now and may lead to some winter kill. If you must prune now, remove only the dead, diseased or broken branches.
Q: We have an Ohio buckeye tree in our yard. Is it possible to plant nuts from the tree and have them grow? If so, what is the procedure? I'm interested in doing it as a fun project with my grandchildren. (Arlington, S.D.)
A: Yes, the Ohio buckeye nuts will grow into Ohio buckeye trees! The biggest problem will probably be keeping squirrels from digging them up for food. The only procedure is that they need a cold treatment. You can plant them directly outdoors this fall, about 4 to 6 inches deep, where you want them to grow, because they do not transplant very easily. Cover the area with screening or hardware cloth, remembering to remove it next spring before growth emerges. Be sure the planting is in an area that gets plenty of sunshine, is moderately well drained and has room to grow. That's all there is to it!
Q: I have three tree stumps that I would like to remove. I am not able to dig holes and put in stump killer and burn it out. I heard that you could get rid of the stumps by using zucchini and putting them on the stump somehow. Have you heard of this or was I misled? (Wayzata, Minn.)
A: I have never heard of that one before! There is stump remover available from local garden centers, where you drill holes into the stump pour in the material, and it disintegrates over time.
You can also rent a stump grinder, or hire someone with one to do it. They can turn the biggest stump into sawdust in a matter of minutes.
Q: How do you tell red mulberry from white mulberry? I would like to grow some from hardwood cuttings (I've read that they root readily) but am not sure which species the local trees are. I want to grow only native trees. (E-mail reference)
A: Think very carefully before you plant a mulberry tree ( either one). The fruits are almost irrationally attractive to birds, and if they are planted in a location that is inappropriate to that kind of attention, you will have a mess on your hands! If you can, try to propagate from a fruitless (male) tree for a cleaner area under the canopy. Of the two trees, the red mulberry (Morus rubra) is more rare and more attractive. It is difficult to describe the subtle differences but I will try: the white mulberry leaf is very polymorphic-- that is, some leaves are lobed, others not; the base of the leaves could be cordate (kind of heart shaped), others not; the veins on the underside of the leaves could have a slight pubescence (peach-fuzz) to them. The red mulberry has a much handsomer, dark green leaf that is broadly oval, and comes to an abrupt point, with some being two or three lobed (but not as frequently as the white); the underside is dark green and softly pubescent, not confined to the veins.
Q: We planted bare root trees this spring. Is there anything special we should do to prepare them for winter? Should we continue to water them up until frost or longer? Also, when can grass be seeded this fall? (Aberdeen, S.D.)
A: Keep your trees watered until they are defoliated. This doesn't mean daily watering, but do not let them go into the winter months dry. Yes, grass seed can be sown this fall. Starting around Labor Day weekend is an ideal time to carry it out.
Q: Our trumpet vine is destroying our house foundations and neighbor's driveway. We cut down the vine, but its runners are popping up all over the place and pushing through the asphalt driveway. This is an emergency! Does anybody know a way to destroy the darned thing? We have been putting stump remover (potassium nitrate) into the stump and have been pulling out the runner sprouts coming up to surface, but no use. The vine will soon cost us extensive foundations repairs, a new driveway for the neighbor or maybe even several more asphalt toppings. (E-mail reference)
A: Wow! Sorry to hear that. You are doing the right thing with the stump killer; try "painting" the emerging sucker growth with Roundup. It will take persistence, but you should win!
Q: We have a long row of basswood trees planted in the grove on our farm. My husband and I are having a disagreement over how they should be pruned. I want to prune them so that they are shaped like trees, taking off the bottom branches each year. My husband thinks that they should be more like big bushes and wants to leave all of the growth on them so they are bushy from the ground up. Are either of these two ideas right or is there a different way that they should be taken care of to get a properly shaped tree? (E-mail reference)
A: You are both right. It all depends on what you want from your trees, a hedge barrier or a stately row of trees that are limbed up to view beneath. The former is more a European choice, while the latter is more American. It might all boil down to simply whether or not there is anything worth while looking at beyond the trees. So, take your pick!
Q: I have several large deciduous trees in my backyard (oaks and maples mainly), and I wish to hang a couple bird feeders (suet feeders) from the trunks of a few of them. I figured I would just use nails to hang them, but I don't want to injure the trees. Is it okay to hammer just a single nail into a few trees, and if so, are there certain metals that are better to use or that I should avoid? Suspending the feeders from the branches via rope or cable is not an option in my particular case. (E-mail reference)
A: Although it is not recommended as a good treatment for the tree, a single nail being driven in for the purposes you state should not injury a healthy tree. Go for it! The birds will thank you.
Q: Is water from the sump pump safe for occasional watering of trees/bushes that we planted May, 2001? I have been doing it but heard on a gardening show it is not a good idea because of minerals or whatever the water picks up going through the soil. (Grand Forks, N.D.)
A: You use the term "occasional," which will not hurt any plant material except the most salt sensitive. However, as the sole source of water for the trees and shrubs, I think you would find yourself in trouble very quickly. Established turfgrass seems pretty tolerant to sump water if it is "occasionally" moved around. I wouldn't direct it toward any herbaceous plantings unless they are reputed to be salt tolerant.
Q: Can you tell me what kind of tree this is? It is about 15 feet tall, bushy, and grows in thickets. This year was a very good one for fruiting, but I haven’t tried using these fruits for anything yet. (Minot, N.D.)
A: Thanks for the good sample, which turns out to be a hawthorn, a member of the rose family. The fruits can be eaten, but they are not tasty. I would suggest leaving them for the wildlife.
Q: Everyone in town loves this tree when it is full bloom, but I haven’t found anyone who can name it. Also, where do I get trees started? We get little trees sprouting up all over, but the landlord won’t let them grow until fall, so we can’t transplant them when dormant. (Faulkton, S.D.)
A: The tree is a black locust. Local nurseries should carry them.
Q: Can you give me some information on "common American smoke tree seed" and where I can purchase some? ( Fargo, N.D.)
A: The American smoke tree is the Cotinus obovatus, which is common in south-central U.S. landscapes and is closely related to Cotinus coggygria, the common smoketree, which is seen more often in the northern states. There is an outside chance either one could survive in the southern parts of North Dakota, as they are listed as hardy starting in zone 4 in protected locations, but will definitely do better in zone 5 areas. Where to get the seed is a good guess. I would suggest writing to the Arnold Arboretum, 125 Arborway, Jamaica Plain, MA 02130-3519, phone 617-524-1718 or e-mail
Q: Our home was built about 6 years ago in a wooded subdivision. Just this year, in the area of our basswood tree (at the back of our yard and includes our yard and our neighbor’s), we have groups of one to eight plants coming up in our lawn. The ones that I have dug up are attached to roots or can be in a large clump with a thick deep root system of their own. We have cut the lawn area short hoping they would die, but they come back. We have also sprayed them and it didn't seem to do anything. Can you tell me if this has anything to do with our basswood tree, and if not can you send me in the right direction to eliminate this problem? (E-mail reference)
A: I doubt that it is the basswood tree causing the suckering, unless the leaves on the suckers you are digging up are identical to the ones on the tree. Since your home is in a wooded area, it is highly likely that trees were cut down to make room for yours and your neighbor's houses. In doing so, parts of root systems were left behind, some of which have the ability to send up new growth from those root pieces. Poplars, cherries, lilacs, and willows are just a few of the species that are known for this characteristic. The only thing you can do is what you are currently doing--dig or spray with herbicide. Eventually you will prevail, so hang in there!
Q: We just cut down one of my big Red Canadian trees. It was full of black knot. Could you suggest a tree to put in its place? I would like something that turns red in the fall but want something that is hardy to the area and not susceptible to black knot. We also lost a tree to the deer. They rubbed all the bark off of it and it died. This was a flowering crab. Any ideas what I could plant in its place? (Tappen, N.D.)
A: I would suggest planting a hawthorn (spines and all) in both locations. That would keep the deer away and provide food for the small wildlife in the area. They have an attractive red/gold fall color as well.
Q: I would like to grow some fruit trees from stones. Is that possible ? If it is, what is the best way to germinate and grow them? We just built a greenhouse this winter, if that would help in the process. (E-mail reference, Salt Lake City, Utah)
A: The more information I have, the better I can help. Thank you. Stone fruits ( plums, peaches, etc.) have a very hard endocarp (outer shell) that at one time was thought to inhibit germination, but in research studies the germination percentage was actually higher with the endocarp intact. Apparently the embryo was damaged in some instances during removal of the hard outer shell.
Except for the southern species of Prunus, all require a cold stratification period of about 90 days. This is accomplished by placing the stones in a moist mixture of 50/50 sand/peat at about 40 degrees F. This is easily done in the vegetable crisper of the refrigerator. Some germination should be evident at the end of this period. If not, keep the stones in there for another 10 to 20 days, or until germination is evident. From there, it is simply a matter of potting the sprouted seeds up and growing them on in your greenhouse for a season, then allow them to go dormant and harden off. You should have a decent crop of stone fruits in a few years.
Q: What do fruit trees and fruit-bearing bushes need for fertilizer? What about spraying? I don't like to do spraying any more than I have to and am trying to attract butterflies and birds to my yard. I have a terrible aphid problem on a current bush. What kind of spray could I use? Are there some good, simple landscape software programs or web sites that I could get practical ideas from? I love to look at garden catalogs and books but they always seem to be for another zone and assume I have the perfect soil. I have to work around gumbo-on-shale soil and within a short growing season. (E-mail reference, Rapid City, S.D.)
A: Generally fruit-bearing trees and shrubs don’t need fertilization on a regular basis unless you are in it for commercial purposes. I usually advise people to respond to any diagnosed deficiency that shows up. Most yard grown trees and shrubs get adequate nutrients as a coincidence from turfgrass care. To control aphids on your currant bush, I suggest using insecticidal soap as soon as you see them. This is safe material for you to handle, allowing you to eat the fruit without a worry. Spraying, again, should be in response to a diagnosed problem, not just as a prophylactic action. Local garden supply stores carry many lines of insecticides and fungicides that you can use. Simply spray in the early morning or late evening (before sundown) when the insects and birds are less active. Try my website. Just about everything is published there: www.ag.ndsu.nodak.edu/horticulture.htm
Q: I’m looking for information on starting trees from seed, mainly coniferous and deciduous for North Dakota. (E-mail reference, Cavalier, N.D.)
A: There are a couple of good books available "Seeds of Woody Plants in the U.S." USDA publication #450, and "Seeds - Ecology, Biography, and Evolution of Dormancy and Germination" Neither is casual reading, but they should be available at the local library, at least the USDA one. It is a fairly complete book and should answer your questions pretty completely.
Q: I would appreciate any information you could send me regarding native trees or trees that do well in the Midwest. I am specifically interested in Dutch elm disease resistant elms. (E-mail reference, Sioux Falls, S.D.)
A: The following elms have passed the test to date in our trials for DED resistance: American Liberty Elm, Independence Elm, Jefferson Elm, Princeton Elm, Valley Forge Elm, Washington Elm, Sapporo Autumn Gold Elm, New Horizon Elm, Cathedral Elm, Vanguard Elm, Accolade Elm, Dandada Charm Elm and Triumph Elm. Other trees to consider are: 'Stately Manor' Kentucky coffeetree (Gymnocladus dioica); Amur corktree (Phellodendron amurense); Ironwood (Ostrya virginiana); Laurel willow (Salix pentandra). (This is a "clean" willow, not the typical messy ones.)
Q: Will butternuts grow in our area? We have a few walnuts, horse chestnuts and an Ohio buckeye or two in the area, but that is about the extent of our nut crop. (E-mail reference, Williston, N.D.)
A: The butternut should grow in your area. It is hardy to zone 3. You are on the western fringe of its native range. Make sure the soil is enriched with organic matter prior to planting.
Q: I would like to plant a nice shade tree in my front yard but don’t want one that will get too tall. Someone suggested an Ohio buckeye or the Amur maple, but how tall do they get? (Edgeley, N.D.)
A: You could grow the two beautiful cultivars of Ohio buckeye, ‘Autumn Splendor’ and ‘Homestead’. Both are excellent mid-sized trees for residential properties, with excellent red-orange fall color. Amur and Tatarian maples can also be considered, with the same recommendation. Use the named cultivars for good performance, like ‘Embers’ and others. I have one of these in my back yard and totally enjoy it.
Q: My three giant umbrella plants (over the rooftops) are now all but sticks due to the freeze here in central Florida. The lower branches and leaves are intact. Can I cut the tree down to window height (height of other branches)? I see no new growth, and the trunks are about 4 inches or more around. I have had these plants for 14 years. The last time it got down to 30 degrees, the trees came back in full bloom. This time, due to the height, I don’t think there’s much chance. It’s 80 degrees during the day now. (E-mail reference, Florida)
A: The tree should come back if you cut it to where the lower branches are -- about a quarter inch above that point. Once they get to that size it should take more than a 30-degree overnight to kill the thing off. In many cases, a freeze injury like this, coupled with a follow-up pruning like you are intending, results in a better-looking, bushier plant.
Q: I have a dragon tree that has lost all the leaves from being in the shop without heat. The temperature was as low as 16 degrees F, and the tips of some of the stems are soft and black. Can I do anything to save this plant? (E-mail reference)
A: Your dragon tree is toast. If it should revive from 16 degrees, let me know, and we'll clone the most cold-hardy Dracaena marginata ever known and make millions! I advise dumping it and starting over.
Q: A tree advertized in Parade magazine is claimed to be a "super growing flowering shade tree that grows roof-high in just one year." The ad also says it’s hardy to 30 below zero but doesn't mention a zone. Is it something to try in North Dakota? (E-mail reference, Jamestown, N.D.)
A: No, not a candidate for North Dakota! It has too many problems and is hardy only to zone 6.
Q: I have three quaking aspen trees in my front yard. I am having two separate problems with the trees. First, the trees send up suckers in the lawn each year. Is there any way to kill the suckers without killing the main trees? Second, for the past three years the trees have defoliated by early September. The leaves will start to develop lesions around July 1 and then turn black before falling off in September. What could be causing this problem? (E-mail reference)
A: Unfortunately, there is little you can do about the suckers coming up from the quaking aspen in your yard. I have two in my back yard, nestled amongst a wildflower planting, and I have to go in a couple of times a year and prune out some vigorous suckers. This just happens to be a characteristic of the tree. While spraying the suckers with a broad-leafed herbicide would kill them back, it may also weaken and eventually kill the trees. I do not recommend this action. The early defoliation could be caused by a fungus called Marssonina leaf spot. Unfortunately, there is no registered fungicide for controlling this disease. The best procedure is to rake up all fallen leaves in the fall, prune out all dead and cankered twigs and branches in the late winter or early spring, and spray with a lime-sulfur just before bud-break. This acts as a surface sanitizer, possibly controlling any further development of this disease. Then, sometime before the first of July, I'd suggest spraying the trees with a fungicide containing chlorothalonil (Daconil, Ortho Multipurpose Fungicide). This should help control the disease and keep the leaves on the tree for their normal span of time.
Q: I have two American chestnut trees that a friend from Green Lake, Wis., gave me about 15 years ago. He said they have them growing there and he wanted to see if they could take our winters. I really babied them and they died back once but are now 12 to 15 feet high. This past year, 2000, is the first year they bore nuts. That has been very interesting -- they are about the size of a golf ball with spiny stickers on them. When left on the tree, they eventually pop open like an X and the seed falls out. I planted some this fall. Could you send me some information on growing this particular type of tree? (E-mail reference, Dell Rapids, S.D.)
A: If they are truly the American chestnut (Castanea dentata), then you are among one of the more fortunate Americans to have a living, nut-bearing tree! The nutmeat is very edible for both wildlife and human consumption. Don't worry -- the squirrels pounce on them as soon as the prickly husks open, revealing the nut. They are perishable and should be harvested and consumed quickly or stored properly, but for not more than four to six months. Storage conditions should approximate the vegetable crisper of the household refrigerator- - temperature just above freezing and the relative humidity close to 70 percent. Anything significantly higher could result in decay. As far as the trees themselves go, if they are the true American chestnut, their days could be numbered, but perhaps not, since you are outside what was once the natural range of this species. The fungus that came into the U.S. in 1904 kills without exception. If you wouldn't mind, I'd like to see a sample of the leaf when spring comes around. Allow them to open completely, then send me a small branch about 6 to 9 inches long, leaves attached. I'll key it out to determine whether it is the American or Chinese Chestnut. Send the sample in a ziploc bag, dry, in a padded envelope.
Q: Are there any nut-bearing trees native to the Northern Plains? I understand by reading the bulletin by you and Dale Herman that both butternut and black walnut are not native to the region. What about hazelnut? If they are native, what is their preferred habitat? The only "nut tree" as such that I can think of at present is the bur oak. (E-mail reference, Grand Forks, N.D.)
A: Yes, the American hazelnut is native to our region -- in fact as far north as Saskatchewan, and as far east as Maine. They are found in the Turtle Mountains and along our eastern rivers. They grow as a shrub, getting about 8 to10 feet tall, but can get considerably larger if cultivated and given a milder climate. Heights in Ohio were more like 15 to 18 feet, and the spread was about two-thirds the height. You can expect about 25 to 30 pounds of seed for every 100 pounds of fruit collected. To germinate the seed, about two to three months of prechilling is needed. Nurseries meet this by simply sowing the collected seed in the fall before freeze-up. They germinate over a 60-day period, at temperatures ranging from a high of 86 degrees during the day to a night temperature of 68 degrees. They are an excellent source of wildlife food.
Q: Thanks for the prompt reply on the American hazelnut. My question was prompted by a request to me to review a manuscript on Native American Ethnobotany in the Great Plains based on the archaeological record. The author was puzzled as to why there were not more nut remains from archaeological sites in the Northern Plains. I could respond as to the reason for the absence of butternut and black walnut, but could not readily answer to American hazelnut. I can now clarify that matter. In addition, I have long wondered why we do not find charred hazelnut hull or nut fragments at archaeological sites in North Dakota. We do find lots of other charred seeds but to my knowledge no hazelnut fragments to date. Most of our excavation data, including use of techniques to recover charred seeds, comes from our work on the James River and in the Missouri River valley. I assume the American hazelnut naturally occurs in those regions. Could it be that the American hazelnut does not naturally grow in "stands" where the nuts would be concentrated enough to warrant intensive harvest? It might also be that the hull fragments being somewhat thin may not preserve well in archaeological contexts. I'm always interested in those things which are "missing" from the archaeological record but which are known or suspected to have been present on the landscape. (E-mail reference, Grand Forks, N.D.)
A: Glad to help out. Very interesting stuff you told me -- I guess tend to think only of the present and not the archaeological past. My guess is that dearth of any evidence of this nut or the shells is due to the high desirability of the nutmeat by wildlife and the frailty of the shells.
Q: We have a large (40-foot) white pine in our backyard in south Fargo. All winter it has been dropping the last inch to 1.5 inches of the ends of its branches. The ground is covered with these short pieces of pine branches. They are not yellow and do not look diseased. My sister who has a cabin in northern Wisconsin has reported that they were there this past weekend and the same thing is evident with the pines around their cabin. She indicated that there the little pieces even have pine cones attached. Any thoughts as to what is happening? (Fargo, N.D., e-mail)
A: If you look closely at the branches that have dropped, you will note that it is a clean break. The critter responsible for this is a fur-tailed, cute little bounder known as a squirrel. I have the same thing being done to my ponderosa pines as well. For some reason they get into the tree and like to nip the ends off--6 inches to 12 inches at a time in some cases. While I don't like their "random pruning," there is little I can do about it unless I want to try trapping. My trees have long since lost their nice symmetrical shape, but other than that, they are doing OK.
Basically, I'd say you have nothing to worry about. You might consider putting some corn and sunflower seed out to give them something else to chew on!
Q: I am thinking of purchasing a paulownia tree due to its fast upright growth. What are the pros and cons of these trees? (Maryland e-mail)
A: I am glad that you thought to include where you were writing from--Maryland--as my answer for a paulownia tree would be "no" for our northern plains climate!
Eastern Maryland is in zone 7 and western Maryland is in zone 6. This is a fast-growing, coarse-textured tree with heart-shaped leaves that has a reputation for messiness. It provides a very dense shade at maturity, which makes it difficult for grass to grow under it. It's more of a tree for large areas, since it can reach 40 or 50 feet tall with an equal spread.
If you live in eastern Maryland, it is likely you will enjoy the flowers. If you live in western Maryland, the flowers are likely to be killed in winter. The flowers resemble a foxglove flower and have a vanilla smell.
Q: I had two smoke trees in my yard that were broke off, one to the ground and the other is about 6 inches tall. All kind of sprouts came up. Will they amount to anything or should I start with new trees?
We planted 13 acres into grass and white clover. Last summer and fall was good growing weather for dandelions. Is there any kind of spray that will kill only the dandelions? (Pelican Rapids, Minn.)
A: Your smoke "trees" are Cotinus coggygria, a plant that is more of a shrub rather than a tree--getting about 10 to 15 feet tall and as wide. Cotinus coggygria is definitely hardy in zone 5 but questionable in zone 4. You must have grown it in a protected microclimate. If it was up to me, I'd let the sprouts take off and see what develops. It will be interesting at least and possibly attractive and functional.
To simply take out the dandelions and not kill the clover, I suggest using 2,4-D. It may toast the clover somewhat, but in my experience it has always come back. Be sure to follow label directions.
Q: We are thinking of replacing some old trees with a poplar and a Russian olive. Do we need to worry about the roots that are left from the old trees?
Also I have been planting wave petunias every year since they came out, but this year they only had about half as many blossoms as other years, and the leaves were real slender. Other people we talked to had the same problem. We have saved some seed, but we are wondering if it could have been caused by the weather? (Litchville, N.D.)
A: You are OK! Any remaining root material will simply rot and eventually provide nutrients to the newly growing trees.
The petunia was a fluke. And, I doubt you will get anything at all like the wave petunia from the seed you saved.
Q: I recently discovered that my young aspen was damaged. What should we do to protect the tree now that the damage is done? ( Garretson, S.D.)
A: Keep the damaged area of your aspen wrapped and dry through the winter. Next spring you should see some callus tissue starting to "roll-over" the wounded areas, to begin healing.
Q. What can I do to protect my trees from winter injury?
A. If your area of the state has been dry, then the first step toward protection is to make sure of ample moisture in the root zone. Plants can then build reserves in their tissue that will help them resist the vagaries of our winter weather. Wrapping trunks of thin-barked trees with tree wrap up to the first branch will help to reduce sunscald. Remember to remove it prior to new growth beginning next spring.
Any evergreens with a historical record of winter burn should be protected with a barrier of burlap on the south, west or windward sides to block the sun and wind. The application of anti-desiccant sprays is especially helpful as well. Research has shown that these sprays are most protective when applied during late winter thaws (February-March) than at this time of year. This is because the sunlight intensity is increasing, causing the evergreen needles to lose moisture that cannot be replaced because of the frozen branches or soil.
Rodent damage from voles and rabbits is a reality in our part of the country. To protect vulnerable trees, enclose the trunk with a cylinder of quarter-inch hardware cloth or white drain pipe. Here's the trick: get the cylinder to go above the snow level to be effective--an impossible task during some winters.
Other means of protecting can come from repellent sprays which must be re-applied, and all vary in effectiveness. I have found it easier to simply make other food available for them, such as cracked corn and sunflower seeds. They seem to prefer that to the bark of my trees and shrubs.
Q: The leaves of my trees were scattered with translucent coloring this year. What's wrong? (Jamestown, N.D.)
A: Mostly, nothing to worry about. The colors indicate cool conditions that cause a breakdown in chlorophyll and the expression of the colors red and yellow within. Now, if these same colors show up next spring, there is likely something to worry about!
Q: Every year about Oct. 10 I fertilize all the trees in my front and back yards. Then I put my soaker hose on and water them thoroughly. I can't afford to water my whole lawn, but I would like to keep my trees. I've been told that the root system on these trees is so far down that I am wasting my time. Is this true? (Ipswich, S.D.)
A: Someone doesn't know what they are talking about! The root system of a tree does not go beyond its capacity to absorb air and water. Most of the feeder roots--that is, those which take in the nutrients and water are within the top 12 inches of the soil. Continue what you are doing! The trees are obviously benefiting from it!
Q: I saw a tree growing in Lexington, Ky. The pods were about a foot long. Can you tell me what it is and if it will survive in Minnesota? (Osage, Minn.)
A: The tree is a honey locust tree--Gleditsia triacanthos inermis. And yes, it certainly should grow in your area of Minnesota since they grow up here in Fargo! They make a very attractive shade tree, providing dappled shade/sun under its canopy and thus allowing most species of turf grass to thrive.
Q: I have two horse chestnut trees that were planted by squirrels. Is this a nice tree to plant in my yard in front of my house? When would be the best time to transplant them? (Lidgerwood, N.D.)
A: They are most likely Ohio Buckeyes, which are in the same genus as horse chestnuts, but are a little hardier. I have found that fall transplanting works best. This species has a fleshy (tap) root and is somewhat difficult to successfully transplant. Wait until the tree is defoliated, and then dig the hole where you want it. Try your best to dig a ball, the same size, around each tree. Tie strips of burlap around and under each ball to help hold it together, and move it carefully to the new site. Be sure to water it quite well. If you're lucky, the moved trees will re-establish in the new site.
Q: I am wondering if there is any way to preserve trees after they have been cut down. We cut it into pieces and brought them in the house to dry, but they mildewed. I would like to paint a picture on them, but I am also not sure how to preserve them. (Carrington, N.D.)
A: Without knowing what size pieces you are talking about, I would suggest air drying -- out of the sun, but in a well-ventilated area. You may want to look up the process of decoupage. My parents took my diplomas from the University of Georgia and Ohio State and mounted them on wood and sealed them with something that has not shown a trace of breakdown in decades. Don't worry about the mildew; it can be cleaned off with Lysol.
Q: It is not the water table that is killing my tree. The water table is down and it is still dying. I thought that it might be bugs, but I didn't see any. I have sent a photo. Could you help me once again. (Deer Creek, Minn.)
A: Your photos have given me another clue, I think. It looks as if the trees had soil fill placed over the roots. If I am correct in this interpretation, then this would be the cause of death after so many years. If I am incorrect, then I cannot tell without lab testing for disease presence.
Q: Is it safe to plant new trees now or should I wait until spring? (Cooperstown, N.D.)
A: In no way keep the trees in their containers through the winter. It is best to get them planted ASAP and water in well. Fall planting will allow the roots to establish without competition for top growth. Next spring a well-established vigorous tree will be the result of this effort now.
Q: I have a tree in the yard which has been there 50 years or so. In looking at an article that compared the horse chestnut with the Ohio buckeye, I thought it was a horse chestnut. I'm enclosing the mature seed, which is a pretty reddish brown nut inside a prickly covering. Can you clarify what it is by looking at the samples? (Finley, N.D.)
A: Piece of cake! The difference between the Ohio buckeye leaf and the horse chestnut leaf is like the difference between a Ford Escort and a Ford half-ton pickup. Same species, but the difference in size is obvious enough that measurement is not necessary.
Ohio buckeyes are hardy into Canada. Horse chestnuts are found across the lower Midwest—Ohio, Indiana, Illinois, Iowa, South Dakota, etc.
Everything except the fruit is larger on the horse chestnut—overall size, leaves and buds.
Q. Like so many of your readers, I have a question.
I have a tree which my book refers to as horse chestnut or buckeye. It is a very well formed tree, and for years I have been hoping to try and grow one like it. It has to be watched at fruit time, as the squirrels do beat me to the nuts. I have gotten a few this year. A sample is enclosed.
I have tried other years to plant some seeds that would grow. Any idea you might give me would be appreciated.
We also lost a small grove of chokecherries to that so-called "black leg." For over 50 years there had been no damage. Is there some background on that?
Thanks for any help and keep the information flowing. There is always something new it seems. (Litchville, N.D.)
A. Thanks for writing. I am glad the column has helped you.
The sample you sent was of an Ohio buckeye nut still in the outer husk. If you had planted that nut about 4 inches deep where you would want about a 30-foot tree to grow, it would have germinated this spring, assuming, of course, the squirrels didn't find it!
The disease that destroyed your chokecherries was black knot. That fungus has become so widespread throughout our region that it is difficult to justify recommending this species to anyone any longer. Our current wet, humid summers are believed to be the culprit in making this disease so prolific.
Q. I am enclosing quite a conglomeration of samples from our yard. This has been an unbelievable year for growing flowers, shrubs and trees. I am about to give up on it all. With late freezes, a very long dry spell and then down pours--I don't think plants know what to do either.
I read your column when you told someone that if their hollyhocks had rust there must be oats nearby. Is this perhaps the cause of some of my problems since I used oat straw to cover almost everything last winter and also as mulch this summer? I have removed it all now and am using baled peat moss as a mulch.
I have sprayed our fruit trees with True Value Green Thumb fruit tree spray, but did not begin early enough. The lilac bushes and Mock Orange bush was sprayed with Fertilome Triple-Action and I used Hi-Yield Captan 50% WP Fungicide on the hollyhocks, but I am sure I did not do it often enough. I quit because I was afraid of what the sprays might do to the hummingbirds, bees, and Goldfinches that frequent these plants.
I did have the soil tested where the bleeding hearts are and it was OK in all areas.
I lost three Orange Glory flowers before they were two inches out of the ground. One had worms all over its roots, the other two just died. This happened with several plants in various locations. A healthy plant in one spot with the neighbor plant dead. I do not understand it.
Any helpful hints you can give on any of this will most certainly be appreciated. (Britton, S.D.)
A.Two of your samples, the maple and highbush cranberry, are howing what appears to be herbicide damage. This could come from spray drift or residue in the oat straw you were using.
The rest of your plants appear to be suffering from a range of maladies: hollyhocks, rust; dicentra and mock orange, aphids and possible overwatering; ponderosa pine, winter damage; crabapple, delayed winter damage; honeysuckle and lilac, powdery mildew damage; haralson apple shows some edge frying from possible excess salts. I am concerned about you horticulture should be a happy, healthy experience. You are trying too hard. Lighten up a little and I think everything will look better.
Q: A full-page Sunday newspaper ad said "Super growing flowering shade tree grows roof-high in just one year!" The ad also said the "Royal Paulownia" grows in virtually any soil, requires no special care and is hardy to minus 30 F. Is this too good to be true? Will this tree really grow like this, especially in our climate? (Fargo, N.D., e-mail)
A: Paulownia tomentosa, also known as royal paulownia, princess tree and empress tree, is too good to be true, at least the way it is described in the advertisement. It will NOT survive in North Dakota. It is hardy to zone 6 which is Maryland, Kentucky, Missouri and Kansas. Try it in zone 5, and it will die back to the ground in typical winters. Where it can be grown, it is an extremely messy tree, similar in character to Catalpa, which is hardy here but not desired from an ornamental viewpoint. Where it can grow, it grows extremely fast, and is therefore used for land reclamation. Its very coarse texture through all seasons would not make the royal paulownia a welcome addition to the North Dakota landscape. We ought to be thankful this tree cannot survive in our region.
Q: I have been planning on taking down the old boxelder trees in my yard and replacing them with others. Gurneys has a Douglas pear tree that is rated for zone 4, and a Reliance peach tree rated for zone 4 as well. I would like to know if these do well in our area since we are on the border of zones 3 and 4. Or, do I need to stick with zone 3 plants? I am a novice at gardening and have never quite figured that one out. (Lisbon, N.D., e-mail)
A: Stay with the plants rated for zone 3 or zone 2. I'm afraid you'll be disappointed if you don't.
Q: I live in Kansas City, Mo., and from all of the information I have read thus far, the problem with my tree appears to be a frost crack. I still need to know what effect it will have on the tree in the long run. We think the rabbits got to the trunk late last fall. They ate the bark all the way around the trunk. The split happened at some time during the winter. We first noticed it in January. (e-mail)
A: A girdled tree has no hope of recovery, so you are better off replacing it. The vertical split is known as sun scald but is really caused by frost splitting the trunk after it has been warmed by the sun during the day. In the future, wrap the tree in the fall with some horticultural tape or plastic to both keep the rabbits away and to keep the bark protected from the sun while the tree is still young.
Q: My golden elder has many stalks/canes/trunks (I'm not sure what they are called), that are rotted off right at ground level. What caused this and will this tree live? It is about 15 years old and has been a beautiful tree, and I would hate to lose it. There are still several stalks left, but I know I took out at least half of them if not more. (Tappen, N.D., e-mail)
A: I have no idea what could be causing the stems to die. Try spraying it with lime-sulfur or Bordeaux mixture, which are broad spectrum fungicides and somewhat environmentally friendly. That should arrest whatever is causing the decline, I hope!
Q: I need a fast growing tree for a screen, and have been considering green ash or cottonwood. I read in a gardening supplement in my local paper about the Austree which can grow 8 to 15 feet per year. Usually when something sounds too good to be true it is. What is your opinion of the Austree? (e-mail)
A: My opinion is zero. You are right, it is too good to be true. This is a cross between a willow and poplar. NDSU has evaluated them at various sites around the state, with the results being that they do indeed grow quickly each year, but then die back every winter to the crown. You are better off keeping your thoughts going in the original direction.
Q: Can you tell me what is wrong with the enclosed sample from my tree? For the last 15 years it has been green and never dropped branches until this spring. I water it once a week and it was transplanted about 6 months ago, which is when I think the problems started. Can you tell me what the problem is and what to do to solve it? (Wilton, N.D.)
A: Norfolk Island pines (Araucaria heterophylla) are beautiful but finicky plants! Change something and they defoliate! This can be anything from a change in the watering regime, air temperature, humidity, drafts, and potting soil. If you can, try misting the foliage with distilled water. Make sure the plant pot does not stand in water after watering, but keep the soil evenly moist. Try to reflect on what has changed -- even slightly -- since you repotted. That would be your first clue as to what could be causing this.
Q: I have questions about the yellow-brown look to some of our trees and shrubs. The maple trees turn yellow in early summer, then brownish and the leaves fall of by mid summer. Our Potentilla also does, and our rose bushes have this mid-summer. We cannot tell if insects attack the roses, but the flowering almond bushes definitely have bug attacks, if not both fungus and insect damage. How do we tell whether to spray for insects or fungus or both and when and how often do we spray? Nothing seems to help. (Wheatland, N.D.)
A: If such diagnosis were easy, I, along with thousands of other horticulturists and plant professionals would be out of a job! Here is what I’d suggest without knowing the source of your plant problems:
1.Clean up all fallen leaves this autumn.
2.Spray next spring with a lime-sulfur and dormant-oil combo. That will take care of all overwintering insects and disease spores.
3.Apply a protective spray of Bordeaux mixture on your plants after the leaves have elongated. Apply systemic insecticide like Orthene to non-edible plants where insect damage is suspected.
4.Monitor the plant material for initial signs of trouble. If these steps don’t improve things, then you’ve got real problems!
Q: I have a large vigorous stand of Staghorn sumac on the back edge of my property. I trim back the front edge of the trees each year so I have both new and well established plants. For some reason my sumac do not turn red in the fall like most sumac do. Could they be missing some nutrients or minerals that could be provided with fertilizer so that we could have the normal fall colored foliage? (E-mail reference, Aberdeen, S.D.)
A: Good question. I would tend to think that you are likely being too good to them -- water, fertilizer, etc. Try neglecting them a little and see if that results in better fall color. If not, then it is likely a genetic deficiency and nothing can be done about it.
Q: I know we don't grow chestnut trees in our state...at least I don't think so. A client is asking if its still possible to purchase chestnuts. He claims you can't get them any more. Where would they be grown? (E-mail reference, Cando, N.D.)
A: The chestnut your client is referring to is either the Chinese chestnut or the American chestnut- - Castanea mollissima and C. dentata. The American native was wiped out by a fungal blight which started at the beginning of the last century and is now, unfortunately, only a memory. The nuts were delicious and sweet tasting. The Chinese chestnut fruit is used commercially and is certainly acceptable in flavor and quality, and fortunately is resistant to the blight. Both are hardy to zone 4.
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