Questions on: Ash

Ron Smith, Horticulturist, NDSU Extension Service


Q: We have a lot of green ash trees. They are starting to get some size and looking nice. We also have eight to 10 that are smaller in size. After reading about possible contaminated firewood imports, I'm wondering just how long it will be before some such incident introduces the borers here. Maybe it would be a good idea to pull the small ash out and start planting some other species for more diversity. What do you think? We have planted some silver and autumn blaze maples. I also read about the Asian long-horned beetle. What kind of trees would make good replacements? We need something that grows fast because we are in our 60s. We don't like some of the fast-growing poplars, but maybe there are some good varieties. Would appreciate your advice! (Valley City, N.D.)

A: It is a good idea to have some tree diversity. The varieties you selected are excellent choices. As to the arrival time of these pests, I have no way of making any accurate predictions. They could start showing up in a couple of years or not for a few decades or more. Hopefully, by the time they arrive, the good minds that are working on their control will have something that we can use for protection.


Q: New growth on my ash tree was severely interrupted by freezing temperatures. Is there any reason for concern? Can anything be done to enhance recovery? (e-mail reference)

A: Not much you can do except being patient. Mother Nature, in her infinite wisdom, anticipated such capricious action by the weather and the tree has reserves that will allow it to bud later in the season. The canopy will not be as dense, but the tree will survive.


Q: We planted 200 trees in 2005. Some are green ash. We are wondering if the trees should be pruned this spring. Some have begun spreading out because deer have been nibbling in them. (Bismarck, N.D.)

A: Now would be a perfect time to prune to get them started on the shape you want them to eventually take. You need to do something to control the deer activity or else your best efforts will be wiped out. There are plenty of repellents to select from.


Q: I found your Web site and I've done some other research on the Internet, but I'm still having trouble figuring out what exactly is on my ash tree. I noticed some dried, curled leaves a couple of days ago. Upon close examination, it looked like tiny, white larvae or secretions were on the underside of the leaf. Do you know what this could be? I'm wondering if I need to be concerned and take some action. (West Fargo, N.D.)

A: This looks like mealybug activity, which is a type of scale insect. I would suggest using Bayers Advanced Tree and Shrub Insect Control. It is applied around the base of the tree and is absorbed systemically through the tree's vascular system and then kills the feeding insects. It has a reported effectiveness of 12 months. For it to be effective, be sure to follow label directions


Q: We have a green ash tree with a crack in the fork. The crack extends about halfway down the trunk. It appears that the wood on both sides of the inside of the crack is rotted, but otherwise the tree appears healthy. I checked your archives and found that you told someone with a similar problem to drill and bolt the tree together in March or April. Can we do this now or is it too late in the season? Also, we've been told that our spruce trees have needlecast. The remedy we were given is to spray the entire tree with Dacinin in the spring for the next two to three years. In your archives, I see that you recommend spraying with Bravo (chlorothalonil) or a bordeau mixture for two years in early June and early July. Which is the best solution to this problem? We would hate to lose these beautiful trees. (Jamestown, N.D.)

A: You can bolt the tree now, but I don't like the rotted wood you mentioned. If you can, get a qualified arborist to inspect the tree because you might be wasting your time trying to save it. With the spruce, the recommendation I gave is the only one I know, but that doesn't mean others will not work. If the suggestion came from a qualified individual, then I would believe it.


Q: We purchased a very large ash tree from a local nursery. The nursery used a tree spade to plant it, which was five weeks ago. The last two weeks, the leaves have turned yellow and are falling off. The nursery owner refuses to look at it because he says he would lose $200 an hour if he did. We are very concerned that we will lose this tree after spending more than $500 for it. We have watered it every week and we do understand the horrible hot weather would have caused stress on the tree. We also purchased another tree at the same time that is not losing its leaves. The nursery owner advised us to dig down to the rootball to find out if it was too dry or wet. It was a little dry, but certainly not powder. We are not experts, so it is hard for us to make an intelligent analysis. (Dilworth, Minn.)

A: The tree should not have been transplanted at the time it was. Transporting a tree in full leaf during midsummer almost is a sure-fire pathway to problems. You should have had it moved while it was dormant in early spring or fall. If the tree did not have an annual root pruning, then most of the ash roots were left in the ground at the time of removal. Both of these factors would be enough for the tree to respond the way you describe. If the tree did not have its roots pruned on an annual basis, the tree could die slowly until you can no longer tolerate its appearance and have it removed. The price you paid for the tree was unbelievably low. Normally, a spaded tree that size costs about three times more than what you paid. The advice to keep the rootball wet was good. Don't flood the tree with continuous water. Instead, try to keep everything moist.


Q: Has ash borer been discovered in North Dakota? If not, how close is it? I am questioning whether I am seeing it in a couple of ash trees at my parent’s farm. The leaves are covered with orange spots. If you look closely, the spots appear to be something blooming on the leaf. What do you think this is? Also, I have some cantaloupe plants that were started in a greenhouse at the beginning of May. Should I be seeing fruit development? All I see is bloom. Is there a way to attract pollinators? (Jud, N.D.)

A: The emerald ash borer has not been reported in North Dakota, but it is in Michigan and Wisconsin. Those states are doing their best to eradicate and quarantine the areas where they know it exists. In the meantime, we have the lilac ash borer that is active in our area. Also, there are a host of bark beetles that are causing problems. If the efforts to contain the emerald ash borer continue, it is estimated that it will not arrive in our area for another 10 years. Hopefully, by then, there should be some other effective control, other than simply cutting down the infested trees. The leaves on your trees are showing ash rust. Don’t worry about it at this time, but clean up the fallen leaves this fall. Spray the tree with Bordeaux or Funginex next spring as the leaves unfold and again 10 days later. There should be some fruit on your cantaloupe plants. If not, the vine might be producing only male flowers or it may be a lack of bee activity. Planting borage will attract bees and will pollinate the squash flowers as well.


Q: About a year ago, you really helped us with a lawn problem. Now we have a problem with a mountain ash tree. We have two trees in our front yard. One is fine, but the leaves on the other tree have started turning yellow and the tops of the leaves look rusty. Any help would be greatly appreciated. (Tioga, N.D.)

A: Glad to help. The tree is showing signs of iron chlorosis. Correct the problem with an application of chelated iron in water-soluble form. Spray it on the foliage and under the tree canopy. If you are unable to locate this material, look for Miracle-Gro that is for rhododendrons, azaleas and camellias. It will temporarily acidify the soil and make the iron available to the plant. Hopefully, you are catching the problem in time to save the tree.


Q: I planted a white ash last September. This summer, numerous shoots grew and circled the base of the tree. I assume the shoots are coming off the rootball. Should I trim these back or is this a part of the growing process? Could this be an indication that the tree has a problem? The leaves on the shoots are larger than the leaves on the branches. Thank you for your help and your Web site is very informative. (Dickinson, N.D.)

A: These are suckers coming from the crown of the rootball. It could be an indication of something wrong with the tree because ash trees typically do not sucker in this fashion. Get some Sucker Stopper RTU from a local garden center or supply store. Cut the suckers back as far as possible and then spray the cut surfaces with the sucker stopper. The tree will stop suckering for the remainder of the growing season. Thanks for the nice comment about the Web site!


Q: Is a golden ash suitable for the rainfall and alkaline soils of the Jamestown area? (e-mail reference)

A: Not likely because golden ash hardiness runs from zone 5 to 7. Besides, this species is more susceptible to ash borer than the natives. Also, the fact the foliage is yellow on new growth sometimes drives people crazy because they like the green color. The same problem exists with the golden honeylocust. It’s a novel idea, but poor in practical application. It does tolerate alkaline soils and limited rainfall. Who knows? Perhaps with continued global warming, Jamestown and the rest of the state south of Interstate 94 might become zone 5!


Q: Our two ash trees in our south Fargo yard have developed a powdery, light-green funguslike growth on some of the lower leaves. Some leaves are curling into a ball shape that is sticky. Any thoughts? (e-mail reference)

A: Two thoughts. It could be powdery mildew or likely some insect with a piercing-sucking mouth part that is causing the foliage to curl. The mildew is not going to be overly destructive, but the insect should be brought under control if possible. Contact Kelly Melquist, a certified arborist, at (701) 729-6899 to set up an appointment. He is very busy these days, so I'd be surprised if he could get to you in less than two weeks.


Q: I have a question about our green ash trees. They were planted in the spring of 2005. They developed lesions on their leaves last spring and this year. The leaves tend to curl and turn yellow. Last spring I contacted the forester in Jamestown, but he didn’t seem to know what the problem was. I am coming to Fargo, so I’m wondering if I could bring you a sample. If you are not available, could I drop the sample off with someone? (Edgeley, N.D.)

A: This could be ash anthracnose, but to make a positive determination, you need to send a sample to the plant lab in Waldron Hall at NDSU. Better yet, bring it with you when you come to Fargo. The lab diagnostician is Kasia Kinzer. Her phone number is (701) 231-7854.


Q: Can you tell me where I can get help with our black ash tree? We’ve had the tree for about five years. Last year it did not leaf out properly because many of the leaves shriveled and died. This year the same thing happened. I have noticed other black ash in our neighborhood seem to have similar problems. Can you recommend anything that we should do or someone we can contact to examine the tree? We love this tree and don't want it to die. (Fargo, N.D.)

A: The black ash plantings up and down the valley have been dying off the past few years. We don't have a clear understanding as to why. All the tree experts in the area are stumped and our specialists at the university are working on trying to determine the reason for this decline. I'm sorry, but we can’t offer any help at this time. If your tree should pull out of this or if you know of any black ash trees that are looking good at this stage with none of the die-back symptoms, please let me know. As soon as we know something about what is causing the problem, we'll let everyone know!


Q: We had a landscaping company plant some tree rows for us. How often do the trees need to be watered? The trees are Ponderosa pine and ash. We also have a single row of lilacs running along the front yard. (e-mail reference)

A: Are you talking about a dozen trees or hundreds? The best way to water is by drip irrigation. As to frequency and duration, it depends on the water-holding capacity of the soil, exposure and if the plantings were mulched. The goal is to keep the root zone moist, but not wet. All three species of plants will not do well if their roots stay in saturated soil too long. If you are making reference to just a few trees and shrubs, then simple hand watering two to three times a week should be more than enough, even under the most severe heat conditions, unless they are planted in pure sand.


Q: Is there a spray that will make the fruit seed of an ash sterile? I have hundreds of saplings growing in the yard, so it is quite a task to remove them. (e-mail reference)

A: There is, but it is difficult for a homeowner to apply. You are better off hiring a professional arborist to do the application for you. Such applications, even when timed correctly, only give about 50 percent control.


Q: I obtained a young, white ash in the late fall. I was going to plant it, but the weather took a turn for the worse (as in snow and ice) and I was unable to plant the tree. Do you have any suggestions on how I can keep the tree alive during the winter? (e-mail reference)

A: Keep the rootball frozen, mulched with lots of straw and covered with a tarp until the soil thaws. Plant it as soon as possible.


Q: Does a healthy mountain ash that is 25 to 30 feet tall and planted approximately 20 feet from the house need to be sprayed with Roundup several years in a row to kill it? I want to protect the foundation. Does this species qualify as a weed? (Valley City, N.D.)

A: Mountain ash trees are not weedy or a threat to foundations. It sounds like you have a beautiful tree, so I would suggest trying to do all you can to preserve it. Healthy mountain ash trees are an asset to any landscape!


Q: I planted a white ash called Junginger. I know we have too much green ash in the Fargo-Moorhead area, but are white ash susceptible to the same diseases as a green ash? Also, do you have any opinions about Junginger? I hear it gets a nice purple color in autumn, but can’t seem to find much about it on the Web. (Fargo, N.D.)

A: It is one of those trees with more than one name, depending on where you make the purchase. It also is known as autumn purple. Here is a brief synopsis of what I found on the Web. F. Americana autumn purple equals F. Americana junginger. It was discovered at the University of Wisconsin, Madison, by Karl Junginger (1905-1991) of McKay Nursery, Waterloo, Wis. It was introduced in 1956, has rapid growth, a rounded habit and is seedless. It has a heavy, dark green foliage of pronounced deep purple or mahogany in the fall or a mottled yellow-orange. Unfortunately, white ash is plagued with disease and insect problems too numerous to mention. I hope this cultivar turns out to be an exception to the species. Sorry, I don’t know more about this tree. Keep me posted on how it grows for you.


Q: I have an ash tree that has a large split in the middle. The split is an inch wide and goes from ground level to 7 feet up. The split appears to go to the core of the tree. I think the split occurred during a windstorm back in November or December. I have been told to put a band around the tree, drill holes and bolt the tree together or cut it down. I hate to lose the tree because it is a major shade tree for our patio. My next question is about two ash trees on the other side of my home. They produce large amounts of seeds, but very little foliage. One is a large mature tree. The other is a runt that is 20 feet high with an 8-inch diameter trunk. They all were planted at the same time. There are adjacent ash trees that are very healthy. Do they have a disease or are they slowly dying? (Sykeston, N.D.)

A: If the ash with the split is important to you, then bolt it together sometime this spring, March or April. In the meantime, you might want to wrap the tree with something to cut down on desiccation. The other ash trees can be removed or allowed to go out the slow way! The proliferation of seeds is an indication of decline. The trees probably will die in a year or two. The runt may have a root problem and probably should be taken out.


Q: I read the article in the paper a few weeks ago about the beetle or bug that is killing ash trees in Michigan and moving this way. Is it killing all the ash trees in those areas or will it eventually? Ninety-five percent of the trees along our street are ash. Should we consider cutting down some of the trees (they are probably too close together anyway) and planting some other shade trees? (West Fargo, N.D.)

A: I shy away from the idea of removing trees that are healthy. At the same time, I am in favor of species diversity. In this case, my bias would be toward species diversity against any future calamity. The Asian longhorned beetle is a voracious destroyer and, if the past is a reflection on the future possible successes at controlling this pest, it very likely will arrive in our area in a few years.


Q: In May 2003, I purchased a European mountain ash. It had a few blossoms on it. This year it did not bloom. Does that mean it won’t survive another year? When is the best time to transplant hosta? (Rothsay, Minn.)

A: It could be the flower buds were damaged by a late spring frost before they had a chance to open. If the tree appears healthy, you have no need to worry. Hosta is best divided in the spring.


Q: My mother-in-law has an ash tree close to her house. We have been told it is dying, but it will be a couple of years before it is cut down. She is worried about the roots damaging the foundation. How long can the roots get? The tree is approximately 15 to 20 feet from the house. (e-mail reference)

A: My colleague, Joe Zeleznik, NDSU urban forester, showed me an example of a tree that had “volunteered” near the foundation of a house. The owner cut the aerial growth back each year, not giving a thought to what was going on underground. When the roots and crown were dug up, it was interesting to see that the roots had grown against the wall and were following it down the side, exerting pressure on it. The root was only following the route of the percolating water, but the potential for foundation damage was there if it was at all weak. She does have room to breathe because the tree is 15 to 20 feet from the house. She might want to have a barrier trench put in between her house and the tree if she is really worried. If she has a good overhang on the roof and the weather is not prevailing on that side of the house, the soil immediately adjacent likely stays dry most of the time. Roots will not grow where there is no water.


Q: I had to move some ash trees at a bad time of year. It was late June after they were totally leafed out and thriving. If I didn’t move them, I would have had to cut them down. I have eight years of care invested in them, so I thought it was worth the chance. I kept them well-watered the first summer. The trees seemed ok even though they lost their leaves early in the fall. Last summer they leafed out fine, but a little late. I kept them watered, but they again lost their leaves early. This summer, only a few branches had leaves. I attributed it to a late frost, but they didn’t recover like my other trees. Are they a lost cause? (e-mail reference)

A: I wish I were enough of an optimist to say that everything will turn out ok. I really doubt that it will. Keep in mind that the majority of the feeder roots were removed when the trees were moved, so the trees were essentially living on what stored carbs were in the remaining supportive roots, crown and stem.


Q: I have a purple ash that has a problem with its leaves. They have round bumps on them that look like warts. What should I do for the tree? (e-mail reference)

A: The bumps or warts are likely caused by a gall-forming insect that are only causing cosmetic problems, not lethal ones. There is nothing you can do about it now and it isn’t worth attempting to control it in the future. The pest will likely be effectively controlled by normal predation or differing weather conditions from one spring season to the next.


Q: I was just out to the Wahpeton Armory to look at their black ash trees. They have several trees that were planted in 2001 that are partially leafed out at the top or not leafed out at all. The branches are not dead as they are still pliable and when scratched, still green under the bark. The branches do not have buds. Other trees of the same variety planted at the same time appear to be doing well with no signs of a problem. The trees did leaf out and grow normally the previous two years. All of the trees have landscape cloth with crushed rock mulch around them at the base of the tree. Could this be winter injury? I tend to think it is environmental as there is no evidence of anything else. (e-mail reference)

A: The problems with black ash in our area have been extensively noted. We are attempting to draw a logical reason for the near universal failure. Could it be herbicide use, lack of winter hardiness or a root disease? At this point, the most cogent explanation seems to be winter damage. The temperatures got down into the 30 to 40 below range last winter with little or no snow cover. The thinking is that it probably damaged some of the roots so they were unable to store sufficient carbs for growth this spring. That said, we have found trees that don't fit this scenario. I tend to think there is something environmental going on, rather than something biotic or from herbicide use. Right now it is a wait and see situation. Hope for the best because it is affecting a lot of trees...


Q: I have a question about a Marshall seedless ash tree. This spring the main stem of the tree didn’t bud-out well. We thought it froze, but when I checked it, the tree looks like it has holes worn in it. (Corsica S.D.)

A: The holes could be caused by bark beetle or sap-sucker activity. From what you describe, it sounds more likely to be the former, unless the holes girdle the branch. If you can, locate a certified ISA arborist (check the yellow pages) to see if the tree can be treated and saved.


Q: My ash trees were starting to bud nicely, but then got hit with frost. They now have no leaves and the buds are drying up. They are located in a shelterbelt near our farm. Will they come back? (Dickinson, N.D.)

A: The trees should recover. Mother Nature has a backup to irrational weather so the species can survive. This happened to lots of plants all over the state this year.


Q: We planted a Patmore ash tree this spring. It started getting green buds on it during a week of nice weather in April but then we had a week of cold weather and freezing temperatures at night. Now the tree no longer has any green buds. Will this tree develop green buds and leaf-out this year? Since this is a new tree, what type of fertilizer do you recommend? (Bismarck, N.D.)

A: No fertilizer please! The tree will re-leaf a little later. Mother Nature, in her wisdom, has programmed in such contingencies. Just don't let the tree become water stressed this summer.


Q: Do you have any information on male ash trees? I need your eloquent words to let a homeowner know that his ash tree has some strange growth because it is a male. (Forman, N.D.)

A: How about this simple, factual statement: Ash flower galls result in the abnormal development of male flowers on white and green ash species lasting throughout the winter and are caused by a mite. If that doesn't do it, I don't know what else to say.


Q: We have a 21-year-old white ash tree in our yard. Last year we noticed that several lower branches had died. Also, for the last few years there has been brown stuff hanging on the branches where leaves should be growing. This year it looks like the tree is dying. It has not leafed out and the brown stuff is everywhere. The branches still have green under the bark but the middle of the branch has a soft white center that seems spongy and dry. We really want to save this tree if at all possible. (E-mail reference)

A: Get someone out to inspect the tree, preferably an International Society of Arboriculture certified arborist. They are trained to identify tree problems, make appropriate recommendations and take the necessary action.


Q: I have a young mountain ash tree. Recently I noticed the bark has been chewed off the south side of the tree to a height of about two feet. I’ve wrapped the tree in burlap to protect it from the sun. Is there anything else I can do? Is there a chance that it may survive the damage? (E-mail reference)

A: There’s a very good chance it will survive. The tree is young so it should have plenty of vigor to heal, for the most part, this summer. I suggest removing the burlap this spring to allow air to get to it and aid in the healing. Next fall, wrap the trunk in burlap before the snow flies. Wrap it to the first set of branches to protect it from gnawing varmints!


Q: I have a 35-year-old green ash. All insects seem to like this tree. For the past five years I have been having it injected with an insecticide that kills all the insects. Do yearly injections harm the tree or can I keep doing it indefinitely? I thought that the tree was slow to leaf out this year, but I suppose that it could have had the first buds frosted. (Billings, M.T.)

A: It shouldn’t be a problem as long as the person doing the injections knows what they are doing. You might try a dormant oil spray next year before the tree leafs out. This may solve the problem by killing the insects in their over-wintering stage. The same tree service that does the injection work for you could likely provide this service as well.


Q:  Last fall we planted an ash but I don't remember what kind it is. We over-watered so the leaves curled and fell off. This summer the tree has been doing great.  We have been careful not to over-water. The leaves are curling again and look a little brittle but not as bad as last fall. The leaves aren't yellowing or falling off. Should we be concerned?  (Fargo, N.D.)

A:  It sounds like it could be herbicide residue from a neighbor or in the backfill soil or mulch you are putting around the plant. If that isn't it, then it could be that you have it in a very high temperature and sunlight intense microclimate. Continue your careful watering. If it gets worse, send a sample to our plant diagnostic lab at NDSU.


Q:  I looked at a nice old mountain ash the other day. The homeowner says it was planted about 1970. What is the life span of a typical mountain ash? There are some leaves yellowing, browning and falling off but not a high percentage. The yellow leaves didn't appear to have iron chlorosis symptoms. A lot of the berries seem to be drying up and many have fallen off. I didn't see any symptoms of fireblight. Could it just be going into decline? I suggested they fertilize. (Cando, N.D.)

 A:  This tree has gone beyond the average life of a mountain ash by about 15 years. They are sensitive to poor drainage, alkaline soil, and root rot. It might be time to give the poor thing its last rites. Try fertilization to see if that gives it a little boost.


Q: We live north of Bismarck on a couple of acres of clay soil. In the summer of 2001 we purchased three ash trees that were discounted because of moderate hail damage -- two patmore ash and one fallgold ash. We planted the patmores on the north side of the lot and the fallgold on the south side. I know we took a risk in planting hail-damaged trees but we couldn't pass up a bargain. They seemed to do pretty well that first summer and last summer, despite the dry weather. This year the patmores have little to no leaves on the west side. All the foliage is on the east side of the trees. The branches on the west side are still pliable so they aren't dead. There is also a distinct difference in the color of the bark. The east side is grayish while the west is brown. We did have a strong freeze this spring after the trees started budding but I can't imagine that it would have affected only the west side. Is this just an indication that the trees are not long for this world? Is there a chance they can come back? For what it’s worth, the leaves on the east side look healthy. The fallgold, which is slightly more protected from our incredibly strong northwest winds, is doing fine. (Bismarck, N.D.)

A: The trees may live but will they be an asset to your property? I would suggest replanting the two and keeping the fallgold which you indicate is doing . The true long-term damage from hail will not show up until a few years after the event. You took a chance and got one bargain out of three so consider yourself lucky!


Q: I have some green ash trees that are about 10 years old. The last couple of years I’ve noticed that the bark seems fragile and has been breaking or peeling off. It’s nothing major but it does have me concerned. I wrapped them last year and then took the wrap off over the winter. I have them wrapped again now and I painted any wounds or cuts with pruning spray. The leaves were fine except I did notice one was curled. Any ideas or suggestions? (Stanley, N.D.)

A: Leave the tree alone unless you want to wrap it going into the winter. However, ash trees usually don't need such attention. In 99.9 percent of the cases, green ash trees need little care after planting. In spite of what they go through, there is usually nothing terminally wrong with them unless you get too intrusive by painting wounds with pruning spray and wrapping. One leaf curling is nothing to worry about.


Q: I have a question regarding pruning a mancana ash tree. The tree is 12 feet tall and has developed a second leader. Would removing the secondary leader ruin the canopy of the mature tree? (Fargo, N.D.)

A: Removing the secondary leader shouldn't be a problem but get it done this week if possible, as trees are starting to leaf out.


Q: We have an ash tree that we transplanted by hand. It was about 10 feet tall and straight, but has grown to 16 to 20 feet in 5 to 6 years. The trunk is about 4 inches. It's not bushing out like we'd like and it's growing more to the southwest. I’m wondering what would happen if we cut the top two feet or so off? Would it bush out more, or would it kill it? Also, if we can trim it, when's a good time? (Perham, Minn.)

A: It should bush out and not die. Just be careful to cut back to a lateral branch or bud. Do so next spring before new growth starts.


Q: I bought a marshall seedless ash tree in May 2002. It was doing very well until two weeks ago. The leaves on the end of the branches turned brown and fell off. The nursery said it was a bug and wouldn't hurt the tree. They will spray the tree for me next year. The branches where the leaves fell off are dead from 8 to 12 inches from the end of the branch. Can you tell me what the cause is? Is the tree terminal? The man I purchased the tree from at the nursery said he couldn't believe it and would be out soon to check it. (E-mail reference)

A: I would say it could be any number of things. It could be planted too deep, have cankers, bark borers, or a combination of problems. I suggest that you wait for the nursery owner to come out and check the tree for you. It might not be terminal, but it will probably never be the tree that you want it to be.


Q: We have a 4-year-old shelter belt with a row of green ash trees. Instead of the leaves on the ash trees turning colors after the first frost, ours turned brown and dried up. Why are the leaves on our trees drying up instead of turning yellow like the older ash trees in the area? (Aberdeen, S.D.)

A: Simply genetic variation amongst the species which is nothing to worry about.


Q: I'm having trouble with scale on my trees, especially my green ash trees, where they are so thick that they’re almost on top of each other. The trees have a lot of dead branches. They are also on my apple and apricot trees. I have used ACECAP 97 twice on my ash trees, but was told that I probably shouldn't do it every year. Also I can't use this on my fruit trees. I have sprayed them a couple of times in the fall with dormant oil spray. What can I do before all of my trees die? (Tioga, N.D.)

A: The dormant oil should be applied in the early spring, just as or before the leaf buds open. It sounds like you have a near impossible situation to bring under control. Unless scale is caught early, it can be difficult to eliminate. Timing sprays to kill off the crawler stage is important, but unless you are a competent entomologist you will succeed only by luck. You might try summer oils, which are a lighter consistency and will not be toxic to the plant in leaf. Other than these recommendations, I have nothing else to offer. Sorry!


Q: Is there any thing a person can spray for ash borers this time of year? There are ash tree rows full of the borer larvae, which are difficult to control at this stage. (Minot, N.D.)

A: What a curse to have on your ash trees!! The way I understand the ash borer cycle, if this is the first year of infestation, the larvae are feeding within the bark and could be vulnerable to a systemic insecticide. Typically, this pest takes two years to complete a life cycle, with the second year boring deeper into the wood, beyond the bark/cambial area. At that stage, no insecticide, systemic or otherwise will have any significant effect. The "hottest" systemic insecticide to control these pests is a product called Bidrin, put out by the Mauget Company. It is a restricted use material, so one would have to be licensed to make the purchase and application. Perhaps a local arborist is licensed to do this injection work and could serve your nursery. Other possible practices are to cover fresh wounds with tree wound dressing to prevent further bleeding and entrance of disease organisms; prune out anything that is beyond saving and burn, and finally if only a couple of trees are infested wrap the trunks and basal parts of the main branches in mid-May with burlap or cotton cloth to trap the emerging moths, removing it in mid-August. Repeat this for three years. I hope something here will help you save your trees!


Q: I have an ash tree (Marshall I think) that is about 20 years old. Last year, and more so this year, there are not too many leaves and a lot of dead branches. It looks like it is dying. Is there any hope for it? The rest of the ash trees are doing very nicely in my neighbor's yard. This is in the front yard so hate to lose it. (Groton, N.D.)

A: The tree could be suffering from borer damage. Check the dead branches to see if there is evidence of borer activity at the base, and peel the bark back to see if there is evidence of bark beetle damage. I suspect either or both could be causing the problem. If you can, get a certified arborist or horticulturist out to check over the tree. Something may be getting started here that you don't want spreading to the other trees on your property.


Q: Last year I sent you some photos taken of our ash tree and you stated that it was suffering from an invasion of the flower gall mite. Now I have enclosed some samples of three things that all came from this same tree. We don’t want to lose this tree in our front yard. Is there anything we can do? (Wahpeton, N.D.)

A: Your tree will be all right. You can spray with Malathion or Sevin if the insect problem persists. Nothing can be done about the galls now.


Q: The leaves on my ash trees froze. Will they come back yet this year? ( Linton, N.D.)

A: If they truly froze, they are gone for the season, but Mother Nature is clever. She doesn't expose all of her leaves at the same time to the vagaries of the weather in North Dakota, so a second flush should be taking place in two to three weeks from the buds that did not open early.


Q: I wrote last year about bugs killing my green ash and you suggested to use Neem. I was wondering if it will work without the lime-sulfur because I tried getting it with no luck. I sprayed today and couldn't believe the new holes drilled in the trunks from the outside. A week ago I sprayed and didn't see any holes. The holes are about the size of a small match. I feel like giving up on these trees. (E-mail reference)

A: What you are looking at could be holes from the yellow-bellied sapsucker. They are active at this time of year punching holes in trees to get them to bleed to attract insects, which they then enjoy as a meal.


Q: I looked at an ash tree today (planted in 1998 and about 8 feet tall) that has numerous holes in it, resembling ash borer holes, and a large fresh hole that appears to be a woodpecker trying to get the borer. With the removal of Dursban from the market, what would be a good product to use? There is also a large branch on this tree, about an inch in diameter, that has this insect damage right at the collar, and it extends at least half way through the branch. Does this sound like something seen with ash borers? I thought they just made the entrance and exit holes, or is there more? (Hettinger, N.D.)

A: The nearly over-planted ash tree is no stranger to problems, both insect and disease. The ash borers have a three-year life cycle to maturity, during which time they can raise havoc with the trees they attack. Apparently this tree is under stress of some kind, so I would take it down and replant with something that is more resistant like the Amur cork tree or Kentucky coffeetree. Your part of the country would support these two beauties easily, and they would offer something that is not commonly seen in our North Dakota environment. Both are virtually trouble-free. If the idea of replacing the tree is abhorrent to your client, then lindane is suggested at three-week intervals beginning around the middle of May. To me, spraying that often with a toxic material like lindane isn't worth trying to save the tree. I would encourage replacement.


Q: I need to cut down a mountain ash tree that has fire blight. I would like to know if I can chop this wood up and use it for mulch, or will this procedure continue to spread the bacterial infection to other plants or trees in my yard or my neighbor's yard. (Bismarck, N.D.)

A: It will be a vector for the disease, should there be any members of the rose family nearby (apples, pears, raspberries, etc.). If you compost it first, getting it to a nice high temperature of 140 degrees plus, that would cut down on the incidence of disease and the locking up of nitrogen.


Q: I'm an uneducated tree lover with three ashes in my yard in Colorado at an elevation of about 6,300 feet. Because of the elevation (and the foothills microclimate), my trees are subjected to late frosts. This year's was especially bad, hitting right after the Patmore and Autumn Purple (both about 5.5-inch trunk) leafed out. The frost completely killed off all the leaves. The Patmore (planted in a lawn) has struggled back with about 30 percent leaf coverage, but the Autumn Purple is failing. It put out perhaps 20 percent leaves, though very small ones. They are now browning atop the individual leaf stems and then turning brown. Also, the Autumn Purple pushed up numerous suckers around the base. My front yard ash has a few leaves turning yellow, and I was told this is due to overwatering. The tree is in a lawn and the watering amount hasn't changed over the past three years. The Patmore in the back and the ash in the front both show signs of borers, but I failed to notice early enough to take action against the pupae. I will be vigilant next spring! I realize a leaf sample would be far more descriptive, and can send if necessary, but from this description, can you ascertain what approach I might take to save this beautiful backyard neighbor? (E-mail reference, Colorado)

A: The prognosis doesn't look good. If it were just the frost damage, I would say no problem, as trees of that trunk size can survive occasional nips by Jack Frost and recover nicely the next year. But, since you have indicated the borer problem and the suckers coming up, this indicates the trees are under a lot of environmental stress, and might not be long for this world. If the threes are worth it to you, have a qualified arborist come out to make an assessment for you. Undersized leaves on a re-leafing is normal; borers and suckers are not. An aroborist could see the situation they are in and advise you far more accurately than I can at this distance.


Q: Enclosed are samples of green ash trees that have been sprayed with Malathion for over two years. The bugs must work at night and must be big or a lot of them, because my smaller trees are stripped. A nursery gave me some powder called "Halt" that I mix with water and spray every 28 days following with Miracle Grow and they told me to keep them watered when needed. I don’t feel it’s working, because it started with my dogwood trees. My green ash are next to them and now are getting it. I treated that row but it’s still traveling. My first dogwood has only a green stem, and this is just about where my first green ash is. It hardly has any leaves left. I put in 20 caragana trees this spring, and there is something eating them too. I sprayed them with Malathion with no luck. Could you suggest something that would kill all bugs in this yard without damaging the trees or birds? I have no children near. (Bismarck, N.D.)

A: Use a product containing Neem. It has both insecticidal and fungicidal properties and is not harmful to birds, humans or non-plant-eating insects. It is not cheap, but it is effective. One such product put out by the Schultz company, Fungicide3, controls mites, insects, and a host of fungal diseases. You are fighting a gall-forming insect that needs early season treatment. Spraying now does little good. Early next spring while the trees are still dormant, spray with lime-sulfur and dormant oil to sanitize the trees, then spray with Neem (a biological) when the leaves unfold and again in 10 days. Monitor thereafter and treat as needed.


Q: I have an old large mountain ash that seem to have had something feeding on it. There are shells left stuck to the smallest branches with part of the shells being round, shiny and black. The leaves on those branches are just stripped down to almost nothing. I can tell the feeding took place some days ago as nothing is there now doing any feeding. I think the tree may have a touch of fireblight also. (E-mail reference)

A: Sounds like the perfect description of the pear slug sawfly. With warm weather, we are liable to have a second generation this summer. Insecticidal soaps, summer oils, Sevin, etc. will take care of them when they are present. Usually the tree is not seriously hurt, it just looks ugly!


Q: Our new house has an ash tree in the backyard. The tree took a long time to leaf this spring. Now all the leaves have wart-like projections up to about a quarter inch tall. There are about 10 on each leaf. What can we do to help this tree? ( Dickinson, N.D.)

A: Just be patient. Those are harmless galls that have little or nothing to do with the late leafing of your tree. They likely will not be there next year. Depending on the age of the tree, I would suggest fertilizing it so it will come forth next spring with a little more vigor.


Q: We planted 6 to 7-foot ash trees about six weeks ago. About 10 days ago the leaves started browning and curling and falling off.I have read about anthracnose diseases, but there is also bright orange color along the trunk of the tree. Any ideas? (Gettysburg, S.D.)

A: It sounds like a case of ash rust hitting your tree, along with the possibility of anthracnose. At this stage, there is little you can do about either one. Rake up all fallen leaves for now, and next spring spray the trees with lime-sulfur while still dormant, but when the buds are starting to swell. At the green tip stage of the buds, spray again, this time with a chlorothalonil product such as Daconil 2787, and again with the same product when the leaves are fully grown.


Q: About six years ago I bought two ash trees that were listed as a "North Dakota Hybrid". Two years later I could not find that tree at any place that sold trees I was told that the North Dakota Hybrid may also be called "Dakota Hybrid" At one place I was told that tree was a poor choice and that the "Patmore" ash was a better tree. The two N.D. Hybrids are the best trees I have. They are well shaped and least 25 feet tall. The Patmore ash has grown only a few inches in the past three years. My question is, where can I find the N.D. hybrid ash trees? (Faulkton, S.D.)

A: My goodness, how we try to sell what we have and downgrade what we don't carry! The so-called North Dakota hybrids are several cultivars developed by NDSU's Dr. Dale Herman, and I assure you they are anything but inferior to any other ash tree on the market. He has the patience of Job in evaluating his trials before releasing any selections to the market. His introductions include Dakota Centennial ash, Prairie Spire ash, and Prairie Dome ash. All three were introduced in 1988. As to where you can purchase them, I'd suggest giving Bailey Nursery in the Twin Cities a call and asking them where the trees are being retailed. I know they are being sold at most of the nurseries in North Dakota and Western Minnesota.


Q: We have planted three Dakota Centennial ash trees. Would it be possible to get more information on how to take care of them? They are planted in a sidewalk box. Is there anything special we need to know on their upkeep. (E-mail reference)

A: The Dakota Centennial Ash, selected by Dr. Dale Herman, is a beautiful tree, needing no more care than the run of the mill green ash. It will get about 40 feet tall and 35 feet wide at maturity. It was selected for the oval canopy it has at maturity and the fact that it proved to be hardy throughout the trials across North Dakota. Be sure to keep them well watered through the first two to three years of establishment. Make sure the planter box is never saturated, nor bone dry.


Q: Last summer my young ash trees didn’t leaf out like they should. There were few leaves and some were curled on the edges. Last fall you mentioned this problem and suggested a spray before they leafed out in the spring. Could you please repeat that information before spring? Also, all of our longer needle pines have a lot of brown on the needles. Are they hurt? Does one need to spray them with something? (E-mail reference, Kimball, S.D.)

A: That was anthracnose that affects the ash trees in the spring. Spray the trees before leaf-out, just as the buds are beginning to swell, with lime-sulfur spray. This acts as a good sanitizer and should help to control the disease intensity somewhat. If the weather is in our favor, that too will help. Winter burn is common this year with many of the evergreens across the prairie states. Most will recover, although the needles that are all brown now will likely fall off. The buds that will open this spring should produce fresh foliage that will help to mask some of the winterburned foliage. Spray the trees next year just before freeze-up with an anti-desiccant, like Wilt-Pruf, to prevent moisture loss from the foliage during the winter. Respray the first above freezing day that occurs in February or early March.


Q: Enclosed is a picture of our summit ash tree. There is something on the tree and is also on many of the ash tree in the neighborhood. We treated the tree with an insecticide through a root feeder and also sprayed with Ortho’s Isotox Insect Killer Formula IV in the spring and again in August, but it hasn’t seemed to help. Do you know what is affecting our trees and what we can do? (Wahpeton, N.D.)

A: The ash trees are suffering from an invasion of the flower gall mite. They attack the male flowers on the trees (some ash trees only bear female flowers) causing them to fuse together in a distorted manner. To some folks, this distortion is unsightly, to others, not. For sprays to be effective, they must be used when the blossoms start to form in spring. In my view, as long as the health of the tree is not compromised, it isn’t worth the time, expense, and environmental assault to spray for such a harmless pest.


Q: We want to plant a couple of backyard shade trees next spring, probably basswood or ash. In a recent column you spoke of Autumn Blaze maple. I am not familiar with this tree. How might it compare overall with ash or basswood?

Also, last fall I put in a grape. It really grew this year, but no blossoms. Do you need two? Should I cut it down for winter? (Aneta, N.D.)

A: The Autumn Blaze maple has striking fall color--red to orange,whereas the ash has yellow only and the linden has none. As far as dependability goes, you won't go wrong with any of them.

I assume you planted a Beta grape. If so, there is no need to do anything. Anything else needs protection by laying the vine over in a trench.


Q: The leaves from our two Patmore ash trees are curled, and it appears to be herbicide damage. An Amur maple about 20 feet from the two ash trees has similar characteristics. The only reason I question herbicide damage is that there is a spirea and a Virginia creeper within 10 feet that are perfectly healthy. Any thoughts? (Pierre, S.D.)

A: The symptoms suggest phenoxy herbicide damage. The fact that the Virginia creeper is so close by and unaffected could indicate that the herbicide--whatever it is--is migrating via ground water to the root system. Or, it could be that when the herbicide was applied and the drift occurred, the Virginia creeper was not yet in leaf.


Q: The leaves of my mountain ash started turning color, and upon closer examination we found holes at the base of the trunk in three of our trees. Is there anything we can do to save these trees? Near these affected trees, there are a large oak tree and an apple tree that don't seem to have any symptoms. (Pekin, N.D.)

A: The mountain ash samples you sent show several problems--scab on the foliage, borer damage on the stems and some root rot at the crown. I advise removing the trees. Attempts to save them at this point would be an exercise in futility.

The oak should be OK, but because the apple and mountain ash are in the same family, I would keep a wary eye on that tree and take immediate action should it start to deteriorate.


Q: Can you tell me what is wrong with my ash trees this year? They are a little curly and dried out. I also am wondering what is wrong with my basswood tree? (Sioux Falls, S.D.)

A: There are a couple of problems. Some of the spots are symptomatic of ash anthracnose which hit the tree earlier in the year, and the other is more serious—it appears to be an environmental problem—salts accumulating, drought stress, excess water in the root zone or some spray damage. The symptoms are not distinct enough to say exactly what the cause is. If possible, core aerate around the dripline of the tree and be sure to pick up all fallen leaves this fall.

Your basswood appears ravaged, but it does not appear to be suffering from herbicide damage of any sort. Most of the problem appears to be physical—hail or insect damage—or perhaps planted too deeply? These are generally easy trees to grow, so this one must have gotten off to a bad start. If the tree is still small, you might consider replacing it, or you can try nursing it along with a couple of applications of Miracle-Gro.


Q: Can you tell me what the orange circles on the leaves and branches of my green ash are and how to get rid of them? (Marion, N.D.)

A: Ash trees are having a tough time this year and yours doesn't appear to be an exception. Ash anthracnose is the disease that is hitting your tree, along with many other ashes across the region.

About the only thing you can do at this stage is fertilize with something like 10-10-10, and clean up the fallen leaf litter completely this fall. The tree should re-leaf in a couple of weeks, and unless the tree is in poor health or subject to other stress, it should recover. It is seldom fatal to the tree unless the pathogen occurs several years in a row.

Next spring if it looks like a cool-wet spell, spray at bud swelling with lime sulfur. Two other sprays should be applied, one at leaf expansion, and the second about 10 days later, using Daconil 2787 fungicide, at a rate of 2 teaspoons per gallon of water.


Q: I have a question about my green ash tree. The leaves are curling and when I open them up there are a lot frost white little bugs. Should I spray the tree with something or leave it alone? (e-mail)

A: I would recommend a spray of either Malathion, Sevin or Orthene (which is systemic and contact). They could be mealybugs or aphids (most likely the latter), but either way, we don't want them to get out of hand.


Q: Can you tell me what is happening to the ash trees this spring? So many of the new leaves are falling. Will they get new leaves? (e-mail reference, Aneta, N.D.)

A: The ash trees are being hit hard by a fungal disease known as ash anthracnose. It causes defoliation shortly after leaf-out, but then the tree does re-leaf a couple weeks later. It is usually not lethal to the tree, and there is little that can be done at this time of year.

In the fall, rake up all fallen leaves, and if the following spring appears to be coming on with a cool, wet spell, spray at bud swelling with lime sulfur and fertilize to promote vigorous growth. Two other sprays should be applied: one at leaf expansion, and the second about 10 days later, this time using Daconil 2787 fungicide at a rate of 2/3 tablespoon per gallon of water.


Q: Can fireblight affect green ash? Is the fungus airborne or does it need direct contact? Can I plant a new green ash 10 feet from where the old one has been removed? Does the fungus live in the soil? (Faulkton, S.D.)

A: First of all, fireblight is not a fungal disease, but a bacteria infection. It infects, potentially, any member of the Roseate family. It is airborne and is most troublesome on this plant material after a hail storm followed by warm, humid weather. The denser the population of vulnerable hosts, the easier the disease will spread.

Prune the infected branches ASAP before bud-break. If this arrives after the buds have already opened, place a bag over the infected branch, tie it and cut it off cleanly. Do not use any pruning paint.

Spraying should begin at blossom time, and continue for three more applications, spaced five days apart.


Q: We inherited a black ash, probably the cultivar Fallgold, which is positioned between the street and sidewalk here in Fargo. Having seen few large trees of this ash species I have no idea how wide it will get or how high up I should let the canopy start. It is about 8 feet from a streetlight and our main concern is keeping the branches from bothering pedestrians. Does one try to shape the black ash to have a single strong trunk under these conditions? The tree is only 5 feet high, but I like to prune the branches off before they get wider than a nickel, making sure to cut outside of the branch collar as is recommended these days. What is your advice on shaping this step-tree of ours? (Fargo, N.D.)

A: The black ash is a beautiful tree that is similar to the green ash, except that the canopy spread is somewhat less -- getting to about 15 to 20 feet in your situation, compared to a green ash that can get twice the size.

Ashes in general need little corrective pruning. If your tree has been planted for at least two years, you can then remove the smaller branches that will have the potential to interfere with pedestrian traffic or the street lamp.

This species is not as drought tolerant as green ash, so if we get into an extended period of no rain, then you should give it a good dose of water. Go ahead and get the pruning out of the way now.


Q: I remember reading in your column about spraying ash trees that have all the seeds with a weed spray to help cut down on the amount of seeds produced. What exactly is it, when do you spray, and will it hurt the leaves or new buds of the tree? I have three of 15 trees that have so many seeds that this would really help. (Groton, S.D.)

A: I hope you have me mixed up with someone else, or that someone else isn't using my name and giving such advicebecause I know of no such procedure. 

This is why clonal or named cultivars are suggested in landscape plantingsto avoid problems such as this! If you think ash seeds are bad you ought to experience Ginkgo Biloba fruit. There was a case in Ohio where a homeowner thought they were getting a male (seedless) tree. It turned out to be femalediscovered years laterwhich dropped rancid smelling fruit all over their patio! Talk about someone being angry! 

My only suggestion of this time is to cut down the trees if you find them that offensive. Sorry!


Q: Can you tell me what we should do to treat our ash and apple trees with scale? (Breckenridge, Minn.)

A: Heavy infestations of scale need attention during the late winter or early spring while the trees are still dormant. Use dormant oil spray, and be sure to cover all branch surfaces.

You may have to repeat this a couple of years or more to get good control. But it is worth the effort to save ash trees. Dormant oil is effective and nondamaging to the environment. It also has essentially no mammalian toxicity when used properly.


Q: What do you recommend to spray for needlecast on spruce trees and anthracnose on green ash? (e-mail)

A: Needlecast on spruce and anthracnose on ash can be sprayed with the same materialchlorothalonil (Bravo) or bordeaux mixture. The timing is very important.

The spruce, infected with Rhizosphaera needlecast, should be sprayed twice in a single growing season, in early June and again in early July. This should be done for a period of two years to restore the tree to full foliage health.

With ash, spray the trees as soon as the buds start to swell, and again 10 to 14 days later. The disease is most virulent when the spring weather is cloudy and rainy. This treatment should be combined with selective pruning of dead branch tips that were cankered from this fungus.


Q: Is there something we can spray on our ash tree to slow down the production of seeds? They make a mess in our yard year round. (Drake, N.D.)

A: In the "old days" there was, but not any more. Sorry!

The seedlings are easily controlled with a dilute solution of any broad-leaved herbicide. Just be careful where the spray is directed.

Also, simple shallow cultivation will take care of the emerging seedlings—stopping them dead in their spot.


Q: Can you tell me what is wrong with my ash trees? One has completely lost its leaves, and the other one is starting to lose its leaves. (Hankinson, N.D.)

A: The one that has lost all leaves is due to a severe case of a fungus known as Anthracnose. This flourishes early in the season if wet weather persists. Generally, it is not lethal, and simply collecting all fallen leaves this autumn and spraying the tree next spring just before leaf-out will control this—along with a drier spring!

Your second tree has somehow received a strong dose of herbicide, which is causing the distorted injury to the foliage. There isn't much you can do about this except to wait and hope it starts coming out of it next season. In the meantime, try to keep the tree from going through any environmental stress.


Q: Enclosed is a sample of our mountain ash and a few leaves from a tree that I cannot identify. The ash blooms and gets berries, then it dies off, and is now getting some dead leaves. We also have three apple trees right next to the ash that we were told have fireblight. What can we do to save these trees? We did try spraying Malathion at the time of blossoming, but it didn't help. (Berlin, N.D.)

A: My suggestion is to get rid of the badly diseased apples and mountain ash, and allow the black walnut that is growing among them (probably planted by a squirrel) to thrive.

The apple and mountain ash are members of the same family, and both are susceptible to fireblight, along with other diseases. Once they are hit as hard as yours are, there is little that can be done to save them. Enclosed is a publication of apple cultivars that are more resistant to diseases ("Tree Fruit Culture and Varieties in North Dakota"H327).


Q: We have six ash trees on the golf course in Selby, S.D., with this growth on them. Could you please identify the problem and tell us how to cure it? (Selby, S.D.)

A: Thank you for the beautiful example of ash rust—Puccinia sparganiodes—one of the most spectacular and destructive rust diseases on deciduous trees and shrubs. The alternate host for this rust is any number of marshy grasses.

This rust, along with other species of Puccinia, flourishes when the weather is wet, humid or foggy. Protective sprays (not curative) of Daconil 2787 (chlorothanlonil), Fore (Mancozeb) and Protect will limit the severity of this disease.

Since I am a strong believer in lime-sulfur being an effective sanitizer, I suggest spraying your ash trees with this material early next spring, before leaf-out. Then after the leaves unfold, make applications with one of the other fungicides about every two weeks, according to label instructions.


Q: I am enclosing a leaf from a mountain ash. Can you please tell me what is wrong with it? Also, when should a person transplant columbines? (Walcott, N.D.)

A: It appears that the mountain ash is suffering from poor drainage, compacted soil or too much water.

Columbines transplant easily just about anytime. I have popped them out of the ground to move them around when needed. I generally do it in the early evening and water in. Less stress on the plant at that time.


Q: Enclosed are a few leaves from our ash trees. The older trees are starting to die off, with the lower branches losing leaves as soon as they come out. There is also a lot of brown fungus on the back of the leaves. We have been told that it might be caused by a blight caused by too much water, but we are not sure that is true. Can you please let us know what is wrong with our trees? (Twin Brooks, S.D.)

A: Your ash trees are being hit by two problems: flowergall mites and a fungal disease known as anthracnose. Based on some of your desciptive language, your trees may also be fighting verticillium wilt. Spray the trees with lime sulfer in early spring prior to bud swelling. Then, as the buds swell, spray with something which has miteicidal activity, such as Malathion or Orthene. If the trees are being afflicted by verticillium, there is little that can be done at this stage.


Q: Enclosed is a sample of mountain ash that has never bloomed. It died this spring and I am wondering why. (Devils Lake, N.D.)

A: The primary cause of the death of your mountain ash was a bacterium known as fireblight, Erwinia amylovora, which caused a canker to form on the root collar, killing the entire tree. This species of tree has become quite vulnerable to this bacterium due to damaging winds, hail and normal benign neglect on the part of homeowners.

Insects, birds and mankind are excellent vectors of this disease. It is particularly troublesome when the temperature is warm, humidity high, and convection storms (with high winds) frequent.

Spraying with Streptomycin is one option for protection. Additional materials include Bordeaux mixture and Benlate. 


Q. In late fall of last year I had a 20-foot mountain ash tree moved to a full sun location. The tree mover used a large unit to move the tree. A cone-shaped hole 6 feet in diameter and about 6 feet in depth. Many of the dry brown leaves still cling to the tree. My questions are: (1) Do I need to prune back the branches and (2) Do I need to apply a fertilizer?

Another question is in regard to two North Dakota hybrid ash trees. Both trees are approximately 18 feet tall and 5 years old. One of the trees developed a vertical split in the bark including the cambium layer. The growing outer part remained viable. The vertical split is near the base of the tree and approximately 10 inches long.

I put bark protectors at the base of each of the trees. These are loose-fitting plastic cylinders split lengthwise with holes for circulation to allow for expansion growth. I can not find any insect damage. Both trees had adequate leaf and growth last season. Any suggestions? 

Is there any way to control slugs with a spray this spring or a repellent around plants late this summer?

I read your column every week. You provide many gardeners with helpful suggestions. Thank you. (Faulkton, S.D.)

A. No fertilization or pruning should be needed unless there are broken or diseased branches. The old leaves will fall when the new emerge.

Do nothing on your ash trees at this time. The wound should gradually close. Next fall, wrap the trees before snowfall, remove by April 1.

I know of no sprays for slug control, but there are several baits available, along with the "old beer" trap that works about as well. I have enclosed extension circular H-887, "Controlling Slugs in Home Gardens." Others may obtain a copy from any county office of the NDSU Extension Service, or by calling the Ag Communication Distribution Center at (701) 231-7882.

Thanks for writing and the flattering comment about the column.


Q. These leaves are from our young ash trees in the yard. Can you tell us what this is and what we can spray with? Thank you. (Hot Springs, S.D.)

A. It appeared that your ash tree was heavily infected with a leaf spot disease known as Mycosphaerella fraxinicola.

As bad as this disease looks, it occurs too late in the season to necessitate control measures. It simply causes the tree to defoliate earlier.

I suggest good leaf litter clean up this fall, and if it will make you feel better, a spray with lime-sulfur next spring just prior to leaf-out.


Q. I look forward to reading your "Hortiscope" articles in my paper.

I have a 4-year-old, 5 foot ash tree with leaves that are drying and curling up and it looks like its dying. Can I save this tree? Also, next to it is a flowering crab tree, the center branches keep dying. I have cut the branches off but the whole tree is yellow and sick looking. I have only the lower branches left at ground level. Would there be a connection of the disease between the two trees? Should I remove and destroy both trees? I have two other ash trees in my yard, 10 to 12 feet high and they seem to be doing OK. Any advice you can give will be most helpful. (Garrison, N.D.)

A. Your crabapple tree is beyond hope--go ahead and remove it. The small green ash looks as if it is planted too deeply, or it has been the object of over-watering. It could also be a  possible root rot fungus.

Your large green ash leaf looks "normal" for this time of year, with "normal" stippling from earlier ash plant bug activity.


Q. I am sending you a seedling from a tree. My husband thinks it is from our green ash or mountain ash. The reason for this is our green ash has seeds hanging on it.

Now, I think it is from a plum tree we once had by our house and a neighbor has one by his garage now. Please let us know what it is and how to get rid of it.

We surely do appreciate your information. Thank you. (Kenmare, N.D.)

A. Three good guesses, with the third one being right. It is a plum, but not a seedling. It is a sprout or sucker coming from the root system.

Unfortunately, once these get started they are very difficult to control. Herbicide applications will only be a temporary correction and could end up damaging or having a negative impact on the mother tree.

I had plums in my yard for years until they started suckering everywhere. I cut them down in 1995 and am still digging and spraying sucker growth.


Q. I have written to the Hortiscope before and have received great help.

We now have trouble with a young maple tree, planted beside our driveway. The leaves on the west side are drying up (see the enclosed sample). What could be causing this? I think the small oval leaves may be hail damage. Also, we planted a Marshall seedless ash two years ago. This spring we noticed the bark on the trunk and branches are cracked open. We would like to know the cause and what to do to save this tree.

We do not get the paper, so could you please send us a letter. Thank you. (Mobridge, S.D.)

A. The damage in all cases is abiotic or nonpathogenic. The silver maple leaves look as if they have been exposed to excess heat from an engine or blacktop driveway surface, possibly exhaust fumes.

The Marshall ash responded to the winter sun. Protect this year with tree wrap or white-wash.


Q. I have a question regarding a mountain ash tree that is about 12 years old.

From the sample enclosed, what do you think is wrong and what should the treatment be? I have given it Miracid about 14 tablespoons over the last three weeks. (Mayville, N.D.)

A. Your mountain ash is showing symptoms typical of a root disease or a vascular wilt fungus. They have not been known to recover. The trees that are afflicted with this will show the chlorosis and leaf margin wilting your samples show and will continue to gradually decline. Sorry about the bad news.


Q. Enclosed is a sample from our ash tree. The leaves have been cured up and dried like this for the past few years. We have sprayed them with malathion several times in the past,  but that doesn't seem to help any. Some of the branches are losing all their leaves. Any suggestions and/or remedies? Thank you for your time. (Kindred, N.D.)

A. Your green ashes are showing symptoms of a fungal disease known commonly as anthracnose. It gets started in wet spring weather, causing leaf disfiguring and premature defoliation.

There is no action to take at this time, but in the fall, do an especially good job of leaf litter clean-up. Then next spring, spray with Daconil 2787 or lime sulfur just as the buds break open.


Q. This winter the snow blew into our 4-year-old shelterbelt, leaving just the top 1 to 2 feet of green ash branches exposed. The deer have fed on the tips of these trees. Will this cause permanent damage? Is there anything we should do to the trees? Is there anything we could have done to prevent the deer from eating the branches? Thanks for any help you can provide. (Tolna, N.D.)

A. Simply prune the damaged branches back to a lateral bud or branch.

When the deer population goes through what it did this past winter, I don't think there is much you can do to prevent them from damaging plant material.

The typical tricks of human hair, bars of scented soap, etc., work for occasional grazers. When deer are starving and moving in herds, their feeding frenzy is second only to grasshoppers'.


Q: A mountain ash tree in my yard recently died. My neighbors tell me that there was a mountain ash in the same spot that died as well. Is there something wrong with the soil in that spot? There is a beautiful mountain ash about 25 feet away that seems to have no trouble. Also, I replaced some dying potentilla shrubs in front of my house, but there is one spot where everything I plant dies. Any solutions? (Cavalier, N.D., e-mail)

A: There must be a toxicant of some kind in the soil that is nailing everything you plant. Could be a pesticide residue or construction debris. Mountain ash are also a little fickle in my book. They seem to be prone to fireblight and other diseases in some instances. I'm glad that you have one that is performing satisfactorily for you.


Q: This coming fall we plan to transplant some green ash trees. My question is, how big is too big to transplant? We have a very nice tree in our tree grove that is about 25 feet tall. We have had good luck with 14-foot trees but want to make sure it will be OK to use this larger tree. (Houghton, S.D.)

A: Larger trees transplant successfully with greater difficulty--usually. I assume you are going to employ a professional tree mover to do the job. Chances of success are greater if the mover can come in with the tree spade and simply root prune the tree, leaving it at the site. This will cause new roots to grow during the season, thus increasing the surface area and "softening" the blow of being moved to a new site this fall.


Q: Would it be safe to spray Roundup on the ash seedlings that are coming up in the rock around our house? Also, I have a 1.5 gallon sprayer that I would like to use to do it. Please let me know how to do that. (Gettysburg, S.D.)

A: Ash seedlings should be fairly easy to wipe out. I’d suggest 2 ounces per gallon. If you should accidently get any on the desirable ornamentals, you’ll only get a small foliage burn and not kill the plant.


Q: I have a list of questions for you: 1. I have several different kinds of monarda and have always grown them with no problems. This year several of the varieties have many leaves turning brown and curling up. What is it and what should I do to stop it? 2. I noticed that many of the ash trees in our shelter belt have leaves that are full of bright orange spots. Is this something they will recover from? 3. I have two Memorial Day peonies (the fern leaf kind), one of which bloomed beautifully this year and the other did nothing. The buds turned brown and never bloomed. Both are plants that I have had for many years. Any idea what would prevent the one from blooming? 4. We have many very large silver maples in our yard and they usually produce a huge amount of seeds that litter our yard. The lawn actually looks brown some years from all the "helicopters." However, this year there were very few seeds. What is the reason for this? I hope the trees aren't in some kind of decline because they provide wonderful shade to our yard and are more than 50 years old. (e-mail)

A: I am always happy to answer your good questions. 1. With the weather we have had thus far this spring, it could be a fungal disease like leaf spot or downy mildew. Try spraying with bordeaux mixture to control further development of whatever it is. 2. The orange spots on the ash trees are likely ash rust--Puccinia sparaganoides. The alternate host is a marsh grass. It is usually more cosmetic than destructive. 3. Probably early bud rot--Botrytis paeoniae. Clean up the plant this fall, completely removing all plant litter. Next spring, spray with bordeaux mixture as the new growth begins and repeat in 10 days. 4. Just the opposite. The plant is likely under less stress this year than last. Usually when a plant goes into a heavy reproductive cycle, is an indication that death or near-death stress is coming on. Part of nature's assurance of survival of the species. Also, when many trees have a very heavy year of bearing fruit, the following year is usually a skip or very low fruit production. So, as long as the trees appear healthy otherwise, you have nothing to worry about.


Q: Because of some new construction we had to move a tree that is about 5 years old. We think its an ash tree. We had called in a tree mover, but he called the day he was supposed to move it and couldn't make it. We were in a bind because the person was there to start digging for our basement, so he moved the tree with a backhoe. The tree lost all of it's leaves, but believe it or not is starting to get leaves and green growth at the end of it's stems. We've been watering it a lot and also adding root stimulator periodically. What else can we be doing to help this tree heal and take root in it's new place? (E-mail reference, Grand Forks, N.D.) 

A: The best thing you can do is to encourage the new growth with adequate water and nutrients, being careful to not overdo it. Later in the summer I would suggest backing off on the fertilization and watering somewhat in order to "harden" the plant going into winter. Beyond mid August, I would recommend letting nature take its course -- to a point. If we go more than 10-14 days without a good rain, water it. Don't fertilize any more for the rest of the year. If there are any branches that are not leafing out, go ahead and cut them back next spring. Try to keep the tree from becoming drought stressed for the next two to three years. Beyond that, it should be able to take care of itself with what nature provides. 


Q: Can you tell me if its possible to grow a mountain ash from the orange-red seeds/fruit that are formed on the tree this time of year? If so how should I proceed? (E-mail reference, Syracuse, N.Y.)

A: Yes, you can use the fruit. Here is what needs to be done: Pick the fruits when they are in full color. They need to be dead ripe. If the birds have started eating them, that is a good indicator of ripeness. Next, macerate the fruit to extract the small seeds within the fruit. The seed can be separated from the pulp via floatation or by screening. Once the pulp is floated off, the seed needs to be dried. If this is too much work, then simply plant the seed and pulp together - no problem. If you are going to store the seed, it needs to be cleaned and dried. Sorbus (mountain ash) seeds need to be stored at stratification temperatures just above freezing for about 60 days. Usually the vegetable crisper in the refrigerator works best. Place the seed in a ziplock bag with some moist sand. Again, if you want to bypass this step, simply sow the seeds this fall, barely covering them, and you should get about 40-60 percent germination next spring.


Q: I was asked to look at a mountain ash that looks like it was freeze dried on the spot. It's a tree that's about 16 years old. It is growing between two large green ash trees. There was another mountain ash planted the same time which is beautiful tree. This tree is stunted. The symptoms are that all the leaves are hanging on it but are brown and dead with a few tips that still have some green leaves. It also set the orange berries. The sprouts on the main tree trunk and root sprouts are all dead. The home owner says no spraying has occurred and broad leaved weeds are present in the lawn. There is a lawn sprinkler system in place so I don't think it is due to drought.

Does fireblight hit mountain ash? Would it start from the inside and move out since there are the ends of branches that still have green leaves? (E-mail reference, Ellendale, N.D.)

A: It sounds like a very clear case of fireblight, especially if the client has an irrigation system working around the tree. The system keeps the tree in a succulent state, which then makes it vulnerable to the fireblight bacterium. All they can do now is cut it down and get it out of there.


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