Questions on: Miscellaneous

Ron Smith, Horticulturist, NDSU Extension Service

Q: Are there any pre-emergent liquid herbicides for quackgrass? Please let me know because I heard you are the turf expert. If you know of any good books on North Dakota turf care, I would appreciate it. (e-mail reference)

A: Sorry, there is no selective herbicide to control quackgrass in lawn grass. For a quick version of how to establish a lawn, go to For more detailed information, go to

Q: I live next to a wooded, vacant lot. It seems the weeds get worse every year, even though I put granular weed protection down when the weeds come up. Is there any weed control that I can use to stop the weeds from coming up? If so, what and when should it be applied? (e-mail reference)

A: Your question is too vague to give you an accurate answer. The weeds need to be identified as to whether or not they are perennial, annual, broadleaf or grass types. I would suggest contacting your local Extension office to see if someone can assist you with weed identification and a course of action that will be effective.

Q: Is this a good time to spray Roundup on buckthorn? Will spraying affect nonselected shrubs and trees? Can Roundup penetrate the root system through the bark? (Wahpeton, N.D.)

A: Roundup works on actively growing green plant material. Being dormant at this time of year, the application would be wasted. While it is actively absorbed through green tissue, it is a good idea to avoid, as much as possible, the surrounding woody (or herbaceous) nontarget material. This can be done using a piece of cardboard, piece of plastic, box or anything else that may put a physical barrier between the spray nozzle and the nontarget plants. To get the best lowdown on buckthorn control, go to the Minnesota Sustainable Communities Network Web site at to download some of its suggestions.

Q: I enjoy your gardening column. I have received a lot of good information, but as yet no one has asked about how to get rid of horseradish. We have kept it at one end of the garden, but it has spread across the whole end. We’re thinking of getting rid of it, but we’re not sure it’s possible. We keep digging it up, but it just keeps coming back. We seem to be breaking the roots, but not getting them all. Do you know of a way to get rid of it? Thank you so much. (Lisbon, N.D.)

A: Other than digging out as much of the root as possible and scalp mowing anything that emerges in the next couple of seasons, all I can suggest is the use of a chemical weed killer, such as Trimec or Roundup.

Q: Do you have any suggestions for killing horseradish that is trying to take over my strawberry patch? I pull the leaves, but the roots remain. (e-mail reference)

A: The only way I know is to get a Dutchman's hoe (oversized pickax) and chop every root out. It may be easier to move the strawberry patch somewhere else.

Q: A homeowner in Harvey has an unwanted vine. She is concerned it may be poisonous. It is nonwoody, with new or young leaves that are a buckwheat type and close to the same size. The mature leaves are about 3 inches wide and 4 inches long with a small subleaf at the bottom on each side of the stem. The petals are purple to lavender, with a yellow center. The berries are reddish/orange in a teardrop shape. The berries have several small, soft seeds. (e-mail reference)

A: Throw the specimen away. I would say the plant is bittersweet nightshade, which is a perennial that easily can reach 10 feet in height. It isn't poisonous to handle, but the fruit is if consumed. Other parts of the plant are poisonous as well. Birds relish the fruit when it is ripe and do an effective job of spreading the seed. To be on the safe side, I suggest wearing gloves and a long shirt to pull this plant out of the ground, just in case she happens to be allergic to the juices. Thanks for the good description.

Q: Can Virginia creeper be grown on brick without damaging it? (e-mail reference)

A: It can be grown on good or new brick facades. However, think carefully before doing this. Think ahead 10 to 20 years to see what the result will be. If you don't like it or it attracts too many birds and/or insects to your liking, it is a pain to get it removed.

Q: Can you help me identify a very fine, long, sprout-type weed that a local homeowner found in her garden? It has a long stem with very small, white flowers on the ends of the stems. It was found growing around some flowers she had planted from seed. The weed is spreading. Could this have come in with the flower seed? Also, is there a cottony scale that attacks cotoneaster? The leaves are gathered in almost glued masses around the stems. Fine, pure-white cottony material surrounds some of the masses and partially travels along some stems. I found one small, 1/4-inch larval crawler, but only one. I'm also wondering about uglynest caterpillar. (e-mail reference)

A: The weed appears to be dodder, which is a parasitic weed that only grows by penetrating the tissue of host plants to obtain water and nutrients. Seedlings must attach to a suitable host within a few days of germination or they die. Threadlike, leafless stems twine around the host plants, which eventually creates a tangled mat. Each plant produces thousands of hard seeds that can remain dormant in the soil for years. The beast attacking the cotoneaster is probably the pear slug. It has nothing to do with pears, so let's call it a cotoneaster slug, which also has nothing to do with slugs! It simply is the larvae of sawflies that have a taste for cotoneaster. The problem can be controlled by spraying with Sevin or Orthene.

Q: Do you know what weed is cloverlike with small, yellow flowers that have been taking over lawns lately? What is best to spray on them? (e-mail reference)

A: It could be oxalis because black medic doesn't show its colors until later in the season. It pulls out easily, but that can be too much work. Using Trimec should do the trick.

Q: I have tried to find some information about broadleaf control in raspberry plants, but haven’t had much luck. What options do we have? (Arthur, N.D.)

A: About the only thing I can suggest is very careful spraying with Roundup. The stuff that is approved for commercial plantings is not available to homeowners.

Q: I have consulted a reputable mail order nursery house about the name of an invasive weed creeping in my lawn, but it could not help me. This weed is shaped like a shamrock and very dark green in color. The weed killer I applied in early spring didn’t work. Can you tell me what product I can use to get rid of it? (e-mail reference)

A: The weed is oxalis, which is a very persistent weed! It can be taken out with Trimec. Try to locate some at a garden center and follow label directions.

Q: I have a horrible problem with morning glory/bindweed. It is invading my yard and the roots seem to never end. Is there a solution to getting rid of this monster? (e-mail reference)

A: Do repeat applications of Trimec.

Q: Bishop’s weed is taking over the edges of my garden. I've heard the weed is unstoppable and undeterred by Roundup. Any suggestions? (e-mail reference)

A: Let this be a lesson to all who read this column. Bishop's weed, Aegepodium podgaria, also known as goutweed, is an invasive, herbaceous perennial that creeps through rhizomes. Through aggressive competition, the weed eliminates other species of plants. The best control is probably glyphosate (Roundup), which should be applied with a sticker-spreader material to make sure it translocates through the plant. You also can try any dicamba-based herbicides, such as Trimec, which is selective to broadleaf plants. It will be a long and tedious battle no matter what methods of control or elimination you try. Don't purchase the RTU version of Roundup. Get the straight chemical and make your own mixture following label directions. It will be more potent.

Q: I really enjoy your gardening column. I have learned so much from you. You have helped me in the past, but now I need your help again! I have some chive seeds that were given to me. When do I plant them? Also, I have this weed, “common purslane,” all over my garden. How can I control it? (Dazey, N.D.)

A: You might want to save the chive seeds until next spring. “Common purslane” is an annual weed that is edible and tasty when mixed with other salad greens. To get rid of it, you can use Treflan early in the season as a pre-emergent herbicide. It is found in products with the label name Greenview Preen. Be sure to read the label directions when using this material. Another way to control purslane is to cover the soil with about 3 inches of organic mulch. Thank you for your nice comments about the column. It is great having a loyal reader like you!

Q: I have 10 acres of land. Ninety percent of the land has prickly pear growing on it, but I want it gone! I have put fertilizer on it, poured diesel and even put salt on it. I have sprayed with professional Roundup, but nothing seems to faze it. My friend told me to use Remedy, but it is far too expensive. On the Web, I found a moth that is a natural predator; however, the state won’t allow the moth. I am at my wit’s end. Do you have any suggestions? I’d really rather go natural, if I can. I am desperate. I did dig some up and burn it, but to do the whole field would take years. Can you please help me? Thank you so much. (e-mail reference)

A: I am sorry, but you have exhausted all the options I would have suggested. Perhaps someone who reads the column can give us some insight on something that will work.

Q: This spring I noticed a wildflower growing in a friend’s pasture. We haven’t seen this plant before. It’s a low-growing plant that has fern-type leaves and dark purple blossoms. I have been told it’s a wild licorice plant. I have seen it growing along the ditches in the area. Will it harm the integrity of the pasture the way leafy spurge does or is it just a nice wildflower? Will the cattle eat this plant? If it is a plant that needs to be controlled, what pesticide do you use to eradicate it? (e-mail reference)

A: Wild licorice is found throughout North Dakota, east to Minnesota, and northwest to Washington and Alberta. It’s a perennial that forms tough, deep taproots and interconnected root crowns. It is a legume, growing about 18 inches tall in North Dakota. Botanically, wild licorice is known as Glycyrrhiza lepidota and commonly found in wetlands or coulee bottoms. Grazing seems to have little effect on the density of this plant. It is not listed as being poisonous to livestock. I would say it is invasive, given the right conditions, so the fact that it got started in your pasture would be a red flag to me that this species would be “happy” to spread throughout your pasture! Get the plant out as soon as possible by digging or with Roundup.

Q: I have a small, flowering weed that grows around my LP tank. I kill it every year, but it keeps returning. It also is spreading out. Can you tell me what this weed is and how to get rid of it? (e-mail reference)

A: I need more information than you provided. Obviously you are not killing it, just burning back the vegetative growth or allowing it to go to seed. The seedlings are what you see coming up. For proper weed identification, we need the weed’s geographical location, a photo or description of the foliage, time of year it appears and when it flowers.

Q: I have creeping clover that is taking over my yard. All the stems emerge from a single point at the base and spread out. It has small, round yellow blooms. Is it susceptible to any specific weed spray? I’m also looking for a low-growing ground cover to go between stepping stones that is durable enough to handle some foot traffic and zoned Region 4. I have eliminated moss, as this area would get a fair amount of sun. (Sykeston, N.D.)

A: Sedum and dwarf yarrow quickly come to mind. They are not known for their foot traffic tolerance, but both are fairly persistent and should recover. As for the creeping clover, Trimec will take it out with repeated applications.

Q: What effect, if any, does trimec broadleaf spray have on pine trees? Would 2, 4-D be a better choice for broadleaf control? (e-mail reference)

A: It could have negative impacts as it is soil active. If you can control them with a 2, 4-D product, do so.

Q: If you have ivy growing on a brick wall, in time, does the ivy damage the bricks and mortar? (LaMoure, N.D.)

A: In time, yes. But, the damage is slight and only after a great deal of time has passed, probably 25 to 30 years (unless it is a poor brick and mortar job). The problem usually arises when the owner tries to remove the old vine and finds the aerial holdfasts are anchored into the wall. Thats when the wall comes tumbling down in bits and pieces.

Q: I am enclosing a piece of an invasive vine that is all over my flower garden. I can't seem to locate the source of this creepy plant. When I try to dig it out, it keeps going and going, so I end up snipping it off. I thought it might be some sort of willow whose roots seem to crawl and appear everywhere. Is there anything I can do to keep these troublesome invaders out of my garden? (Carrington, N.D.)

A: This appears to be a smartweed (polygonum spp.). It is an annual, so it will die down this fall. Apply Treflan next spring before new growth begins to see if you get any control.

Q: Can I purchase lythrum in North Dakota or is it considered a noxious weed? I think it makes a very beautiful plant in a perennial garden but I know most states have outlawed it. If the state doesn't allow it, can I purchase it somewhere else or is there a comparable plant I could grow instead? I have tried lavender but it will not come back. (Tioga, N.D.)

A: By law, you cannot purchase or own lythrum. You can use liatris (prairie gayfeather) in much the same way that you use lythrum. It is completely legal, readily available and hardy for our environment.

Q: What would be the proper procedure to clean my hand pump weed sprayer after using roundup or using Weed B gone? I would like to use the same sprayer for both. (E-mail reference)

A: Bad idea. Use separate sprayers.

Q: I looked at a yard where a large tree had been removed years ago. The dirt was also removed and large raised beds were put in using new dirt. Even with all that work they still have mushroom problems. The mushrooms come up in large four to eight inch clusters and push everything out of their way. It appears as though they are spreading but we have had a wet spring. (Hettinger, N.D.)

A: People can practice their golf swing on emerging mushrooms if they wish. Some people claim a 10 percent solution of bleach poured on the areas where the mushrooms are originating from will work. I don't like that idea too much because, at best, it has only a temporary effect. I don't like putting even a 10 percent solution into the environment. Mushroom growth will be the worst right after frequent rains but will disappear when we have drier and hotter weather.

Q: A young lady brought me an egg shaped white thing that was growing from the base of a tree. It is not a mushroom but is shaped like an egg. It is rather soft and about an inch and a half long and about an inch in diameter. It appears it grew out of some kind of sheath as there is dried up sheathing around the base. (Lisbon, N.D.)

A: While not a mushroom, it is a member of the family. They are unromantically referred to as "conks." They are an indication of internal rot taking place in the tree. The tree owner should get an arborist to take an increment boring of the tree to see how far along the rot has advanced. The tree may need to be removed immediately to prevent property damage or personal injury.

Q: I have a split leaf stag horn sumac. The top is not growing but the middle and low part of the bush is taking off like crazy. Is there something I should do to it in the fall or spring? (Fargo N.D.)

A: Cut out the dead material and allow the emerging growth to take off. This often happens with sumac in our area. During the winter there is a die-back of the aerial part of the plant, with the rhizome surviving and sending up new growth.

Q: I have a problem with a plant called nightshade. I used 2,4 D but that didn't work. (E-mail reference)

A: You should be able to do it in with Roundup. Use it during active growth before very hot weather sets in.

Q: I am having reoccurring problems with quackgrass in my garden. Can you tell me how to get rid of it? It starts out as a fine grass and then, as it grows, gets a hard stem to it. I have tried Roundup but it didn’t work. (Jamestown, N.D.)

A: Try Roundup again. Buy the already-prepared formulation that is available at retail outlets, as it has a sticker added which should make it more effective.

Q: Is Preen weed preventor harmful to birds? I want to sprinkle some beneath a bird feeder to prevent the bird seed from sprouting but I don't want to harm any birds that may ingest it. (E-mail reference)

A: Yes, it is harmful to birds. If you have trouble with seed sprouting, nuke it in the microwave for two minutes at full power before placing in the feeder. That will kill the embryo and prevent germination and won’t harm the birds.

Q: Any suggestions on lilly of the valley? They are overtaking my back yard. (E-mail reference)

A: Write a book if you can figure out what to do about lily of the valley! Their waxy leaves resist herbicides. I have found that pick-axing the plants is the only way to get rid of it. Death, taxes, and lily of the valley.

Q: Please tell me what this weed is. It is low-growing, and hard to destroy. What chemical should I use? (Elgin, N.D.)

A: The weed is known as knotweed, which is an annual and will be killed by the autumn frosts. Early next spring, March or April, spray with a 2-4,D-containing product (something that kills broadleaf weeds) and correct the compaction that caused it.

Q: A while back you mentioned using a wetting agent with Trimec for use on thistle. What do you use for a wetting agent and how much? I care for two cemeteries and a park besides our own property so I use a lot of Trimec each year. I would appreciate all of the advice I can get to kill weeds. (E-mail reference)

A: Where ever you get the TRIMEC, should also have a non-ionic wetting agent. There are so many brands on the market, that I am loath to try naming any. Any one of them will do. What they do is make the water "wetter" by lowering the surface tension of the water and pesticide solution, resulting in better penetration of the material into the target pest. The result is an increased potency.

Q: I am sending a sample of a plant that my husband found in our field. We have never seen it anywhere. How prolific is it? How do you get rid of it? Thank you! (Hecla, S.D.)

A: The sample you sent was of common burdock - Arctium minus. This is a biennial, which in your case, has now entered the reproductive stage. I would suggest cutting the flowering stalk back and burning it, then spray the basal leaves with Roundup. It spreads by "hitchhiking" on clothes.

Q: My mother has a Virginia creeper vine on her porch that is under attack from whiteflies. I sprayed it down with the garden hose but am looking for a better means of control. I know Virginia creeper can be damaged from several commercial insecticides such as Sevin. Is insecticidal soap a viable alternative? How about Tempo 2? (Glenburn, N.D.)

A: Yes, you are right about all you have said. Go for it!

Q: Any tips for control of cactus in a grass environment? The area of concern is a cemetery, There is more cactus than could practically be hand spot-sprayed with Tordon. Is there a product to use that will not kill out all the grass, since the whole area must be sprayed? The only publications I can find are ones that recommend either Picloram or a 2,4-D diesel fuel mix, which would be quite tough on the grass. (Hettinger, N.D.)

A: Trimec has been known to take out unwanted cacti, when mixed with a wetting agent. It isn't toxic to lawn grasses when label directions are followed.

Q: I have had my garden in the same spot in my yard for the last four years and not had any kind of a problem until this year. Early this spring I noticed some creeping Charlie coming in. If I kept ahead of it I then kept it under control, but when I left for vacation and came back the garden was just covered with this awful stuff. I spent a week out there pulling "Charlie" by hand out of everything. I thought of using Roundup, but, knowing what that would do I chose not to. Now of course it is all over, including the strawberries. What do you suggest that I do now that everything has been harvested? (Chancellor, S.D.)

A: Can I wish you had used Roundup? Anyway, nuke as much of it as possible without doing damage to your other crops with Roundup. It breaks down immediately in the soil, so leaves no residue. Then, I suggest digging out your strawberry plants, killing off the creeping Charlie with Roundup or ripping it out entirely, and resetting your strawberries. This would be best done in the early spring.

Q: I have a vine with bright red foliage coming up in a lilac bush. I've seen these before and thought they were pretty in the fall. Will it do any damage to the lilac, choke it or whatever? (Stirum, N.D.)

A: It is probably Virginia creeper, Parthenocissus quinquefolia. This is just a guess of course, but that has to be the most likely vine growing in our region that shows brilliant fall color. You can more or less confirm this by checking the leaves; if they are divided into five parts, then that's what it is. If they are not, then it is something else. These are very rambling, aggressive vines that could smother a shrub that it is growing on. I suggest removing it completely, or digging it out after it has gone dormant and transplanting it somewhere else.

Q. I have seen a beautiful plant that someone told me is called lythrum. I have tried to locate it in a local nursery, but no one handles it, and someone told me that it is illegal to grow it anymore. Is there any truth to this? (Jamestown, ND)

A. Unfortunately, yes. This beautiful, durable plant that is not a native species has adapted too well to our North American environment, and is choking many of our waterway systems, wiping out natural food source species like cattails. So lythrum, or purple loosestrife as it is also known, is on the state's prohibited noxious weed list, which means that all such plantings should be eradicated. Resist being tempted by this plant, and know that you are doing our prairie environment good by not growing it.

Q: Could you please tell me what the enclosed sample is? It grows on a fence, wild and covers the fence. (Moorhead, Minn.)

A: Thanks for the good sample of Western wild cucumber. This is a perennial that regenerates from an enormous taproot. As the common name implies, it is a member of the gourd family.

While it is considered a weed, it may or may not be a pest in your location. If it is, dig out the root either this fall if you can get to it before freeze-up, or early next spring just as it is starting to grow.

Q: What can I use to keep grapevines from coming back? I pulled all of them out and was wondering if Roundup would work on them. They aren't by a garden. ( Mandan, N.D.)

A: Funny, isn't it? If you don't want a grapevine, it grows like a weed, requiring a nuclear explosion to get rid of it; try "cultivating" one, and every insect and disease organism in creation is on it to see who can kill it off first! Yes, Roundup should take care of it. But be prepared for multiple applications as the root system is very extensive.

Q: On numerous occasions you have recommended using Trimec for weed control in yards. My question is, where can Trimec be purchased? Several years ago I believe I picked it up at Menards, but now they say they don't carry it. (Lake City, S.D.)

A: If they are not carrying Trimec, what are they recommending for lawn weed control? It might have a very similar formula, just a different name. Trimec is a trademark name of the PBI Gordon Company. I would try local garden centers and stores like Target, Wal-Mart, and K-Mart. Someone should be carrying it in your area.

Q: What is this plant that is growing in my garden? Is it a weed or a desirable plant? (New England, N.D)

A: It appears to be skeltonleaf bursage which is a perennial that spreads by seed and rhizomes. The samples you sent had not developed rhizomes because they were immature. Try to hand pull as many as possible this fall and generously mulch your garden with 3 to 4 inches of bark or peat moss.

Q: I would like to hear your recommendation for kochia control in turfgrass. Do you see damage from Starane use or should you just stick with something like Banvel. (Hettinger, N.D.)

A: I don't know what Starane is, so I cannot pass judgement; Banvel should do the job without being a problem on turf.

Q: The enclosed plant appeared in our garden. Where it came from we don’t know. It did bloom with yellow flowers. Can you please identify the sample for me? (Butte, N.D.)

A: That nasty thing you sent is known as buffalo bur, a member of the nightshade family. This ugly relative of tomatoes and peppers is an annual that is easily controlled with herbicides (or simply pulling).

Q: Can you tell me what the enclosed vining plant is? Also, are you still doing your great column? I can’t remember seeing it lately. (Devils Lake, N.D.)

A: You sent me a good one, something I had not seen for a couple of decades! It appears to be the common moonseed, Menispermum canadense, a deciduous vine that is too weed-like in growth to be of any real value horticulturally. Yes, I still write my weekly columns, but where or when it appears is up to the local editors. You can get the full scope of Hortiscope by logging on at:

Q: This weed is taking over my lawn! What is it and what can be done to get rid of it? It seems to lay flat and I cannot cut it short with mower. The second sample is another sample of a weed that is taking over another part of my lawn. It appears blue compared to the other grass. (Jamestown, N.D.)

A: The first weed is crabgrass, an annual that will be killed with the first hard frost of the fall. Control seed germination next spring with an application of a pre-emergent herbicide. See the NDSU publication Weed Control in ND Lawns, H-1009. The other weed looks like one of the bentgrasses. Spot spraying with Roundup will take it out.

Q: What should I use to get rid of quackgrass? Next, can you tell me how to crack black walnuts and get the meat out? Freezing was one step, but I can’t remember what the next one is. Also, how do I keep webworms from making webs in my ornamental crab trees? (Sioux Falls, S.D.)

A: Quackgrass can be controlled with Roundup or Poast. Roundup is non-selective, while Poast is a selective herbicide. This simply means that Roundup will kill anything green that receives its spray. Would the next step be to drop the black walnuts in hot water? That would cause a sudden expansion and possibly crack the shell. Otherwise, place them on concrete and get a hammer! Webworm control is most effective with a dormant oil spray next spring while the trees are still dormant. That takes care of the over-wintering egg masses.

Q: Enclosed is a vine that came into my flower bed and has spread all over. It is quite woody at the base and the berries go from green to red. What is it and is it something I should try to get rid of? Also, what can I use to get rid of bugs that eat almost everything in my flower bed. I tried Sevin, but it didn’t seem to work. I found cutworms in my hanging planters. I used only commercial dirt. Did they come in the dirt? (Jamestown, N.D.)

A: The vining plant you sent is nightshade, a member of the tomato family, hence the similarity in seed. Yes, get rid of it before the fruit drops and deposits seed. Try Orthene to control the insects. It is both a contact and systemic. That will take care of any feeding insects. The cutworms are the larval stage of night-flying moths. The adult thought your hanging baskets would make a nice home for her children.

Q: I’m enclosing a sample of a weed or grass that has taken over our garden. I’ve never seed it this bad before. Please identify it and tell us what to do about it next year. (Orient, S.D.)

A: The grassy weed is large crabgrass, a flourishing annual in your part of the country. There are plenty of pre-emergent herbicides that can be applied next spring prior to planting that can control it.

Q: Enclosed is a sample of a weed that I’m trying to identify. Could you tell me what would kill this weed that is invading my grass? (Aberdeen, S.D.)

A: It looks like a member of the sunflower family ( Asteraceae) more specifically bur ragweed. This is a tough perennial that spreads via seed and rhizomes. But, like any other weed it is vulnerable to herbicides at this time of year. I suggest a good dose of Trimec with a surfactant before it sets seed.

Q: Can you please identify the enclosed weed and tell me how to get rid of it? My neighbors lawn is just covered with this weed and it is spreading over into my lawn. (Jamestown, N.D.)

A: They are wild violets. Spray with TRIMEC now and again after Labor Day weekend.

Q: A local homeowner read in your column that you can spray Poast in strawberries to control quackgrass. She was wondering if she could also spray Poast in her perennial flower garden to kill grasses. I looked at the label, it did not list perennials. If not, is there anything else she could spray, or other way to control quackgrass? (Steele, N.D.)

A: Quackgrass is the ultimate challenge in gardening! If someone could come up with an "over-the-top" spray of a mixed bed of perennials and woody plants that would selectively take out the quack, that person would make millions. Vantage has the same active ingredient as Poast, is more reasonably packaged, and bedding plants are also on the label. It is labeled for quackgrass.

Q: I’m sending along two samples of weeds in my lawn. I have used Weed-B-Gone on my lawn to get rid of these weeds, but the weeds keep coming back. What else could I use to get these weeds out of my lawn? (Valley City, N.D.)

A: It appears that the weed you are fighting is common yarrow--a tough one to control! This calls for TRIMEC. Apply now and again after Labor Day, and that should take care of it.

Q: I am enclosing a sample of a clover-like plant with small yellow flowers. Can you identify it for us? Also, we have a lot of ground in our yard that has quite a bit of alkali. What perennial flowers or trees/shrubs survive in that kind of soil? (Jamestown, N.D.)

A: You have black medic taking over. TRIMEC is the only selective herbicide that will take it out, but it will require repeat applications. Xeric-rated plants will usually do well under alkaline conditions, and the list is too extensive to include here. Some reference suggestions obtainable through your local bookstore: "Xeric Gardening" by Ellefson, Stephens and Welch, Macmillian Publishing, ISBN#0-02-614125-6; "Xeriscape Plant Guide" by Denver Water American Water Work Associatin, Fulcrum Publishing, ISBN#1-55591-322-9; "Creating the Prairie Xeriscape" by Sara Williams, University Extension Press, University of Saskatchewan, ISBN#0-88880-357-5. You can expect lists containing nature’s toughest: daylilies, sumac, Achillea, etc. All three are excellent books. Any one of them will answer your questions.

Q: Can you please tell me how to get rid of orange common day lilies? They are taking over my blueberries, ground cover, and grass. Is there something I can spray with to get rid of these pests? (E-mail reference)

A: I am sorry to hear these beautiful flowers that help hold the soil against erosion and grow under a wide variety of conditions called pests. But I agree that they are difficult to control and spread with a vengeance without any encouragement. Being lilies, they will be tough to control, and digging may be the only answer if herbicides don't work. If digging is needed, hire it out to a young person and supervise them to make sure they get ALL the rhizomes out of the beds! Herbicide suggestions are Roundup with a spreader/sticker added or TRIMEC, following directions for broadleaf weed control.

Q: I have horseradish taking over my garden plot. I have nothing planted this year, and tried roundup on it, but that didn't take care of it. Is there something that will kill these plants? (Cavalier, N.D.)

A: Yes--blacktop and concrete! If that is too drastic, try TRIMEC with a spreader-sticker. If that fails, then rent a flame-thrower! They are tough customers to get rid of, and perhaps the only way is to dig them out.

Q: I have the enclosed sample growing in my yard. I use Roundup on it, but it only kills it for a while and then it comes back. (Bismarck, N.D.)

A: Small wonder. It is knotweed, which is very difficult to control at this stage of growth. You need to do two things: Correct the compaction which is allowing this weed to establish and flourish by core aeration. Use a herbicide known as TRIMEC. It usually does a better job than Roundup. If you succeed in killing it off this year, then re-seed around Labor Day weekend. Then next spring, apply a broadleaf pre-emergent herbicide that will control Knotweed seed germination. Do this before, April 1, as this seed germinates early.

Q: I have two questions for you. What is the enclosed plant? I also have a problem with potato bugs. What can I do about them? (Jamestown, N.D.)

A: Congratulations! You have now joined the legions of gardeners who have ground ivy (Glechoma hederacea), a member of the mint family that is quite invasive. Get rid of it as you see it, or it will overrun your entire garden. You are smart to get a jump on the Colorado potato beetle. Spray the crop with Bt as it grows throughout the season. This is an organic control that does not leave any residue on the tubers. You will have to spray every 10 to 14 days to be effective.

Q: My wife’s small garden has had a trumpeter vine coming up in several spots for several years. We cannot find the origination of the vine (junk tree area near the edge of the garden). I would like to know if there is a weed killer that I could apply to one of the vines that would travel back and kill the vine at its roots. (E-mail reference, Michigan)

A: Yes, you can try "painting" Roundup on the leaves as they emerge. It will take some time and repeat applications, but it should eventually do the job. If you find the origin of the root system, you can also drench the soil with a solution of dicamba (make sure there are no other tree roots in the area) and that will get rid of the vine.

Q: There are strange looking piles of red globs in about eight places in my garden under and around bushes. At first I thought the dog had thrown up, but that’s not it. It is really gross and I don't have a clue. (E-mail reference)

A: Yes, that is a saprophytic fungus, one that grows on the organic matter (bark mulch, compost, peat moss, etc.) in the soil. It is not a parasite to plants, it just looks gross, like you say. Don't worry, it will not continue to grow and take over your garden. They will usually disappear with drier weather or a little surface cultivation as the season wears on.

Q: I have a problem with moss or mold on a 2-foot strip on the north side of my garage. It is a green color and it is starting to choke out the lawn grass. I was told to use copper sulfate, but it did not work. Can you tell me what I should do? (Napoleon, N.D.)

A: Moss or algae grow in response to the following factors: too much moisture, poor surface drainage, poor light and air circulation. Copper sulfate can be used to correct, but, will not cure. the problem. To do this, core aerate and do some remedial pruning to improve air and light penetration.

Q: I have an answer for the person who wrote about the vine with heart-shaped leaves and turban-shaped purple flowers. It must be Solanum dulcamara, sometimes known as "deadly nightshade." It's a very invasive weed, but great for hiding ugly fences or sheds. Also, potato beetles love it! (Fargo, N.D.)

A: You're right! I've received several responses to that question all saying the same thing. For some reason, deadly nightshade did not occur to me. I just was not thinking herbaceous!

Q: I have been trying to get rid of a weed, but with no luck so far. What can I do? (Pelican Rapids, Minn.)

A: Your weed is creeping Charlie, a tough, deep-rooted perennial that doesn't surrender easily! I suggest an aggressive treatment starting with Trimec, as soon as growth begins next spring. Set your mind for at least a couple of applications to get it under control.

Q: What spray can I use to control leafminers? What causes the bottom leaves of my delphinium to die? There is something wrong with the leaves of two plants I have. I think one is an oak of some sort and the other is a Holland ivy. (Carrington, N.D.)

A: There are several sprays that can be used for leafminer controls. Sevin, Malathion or Orthene. Spray at first sign of damage, and repeat as necessary. Be sure to check for plant sensitivity of any particular insecticide by reading the label.

I have no idea what causes the lower leaves of your delphinium to die. It could be any number of factors such as nutrient deficiency, a fungal disease or environmental stress. It could also just be normal senescence.

The leaves are showing salt damage symptoms. The containers are either not freely drained, kept too wet or the natural water salts--dissolved solids--are too high.

Q: We have a plant that volunteers to grow around here. My mother used to call it a wild cucumber. Recently someone said it was hops. It is a vining plant and very persistent, growing in a gravel driveway, unused spots of land or lawns. Can you tell me what it is, and will Roundup take care of it?

Also, there is appearing on some trees here a "tent." I assume it is an insect of some kind. Most are on the poplar trees, whereby this winter I could torch off most of them. Any idea of what they might be? (Forman, N.D.) 

A: Your mother was right. It is wild cucumber, and Roundup will take care of it.

The "tents" you are seeing are fall webworms. They can be controlled with a dormant oil spray next spring, prior to leaf-out. Any that re-invade can be controlled with a bacterial insecticide known as Bacillus thuringiensis, or "Bt."

Q: I have a vine with heart-shaped leaves and turban-shaped purple flowers with a yellow center, and it has red berries. What is it? (Canova, S.D.)

A: In spite of your good description, I cannot put all the characteristics you describe into a known woody plant species. Honeysuckle has the flower and fruit, but not the leaf shape; Dutchman's pipe has the leaf shape, but neither the flower or fruit, and the moonseed has the leaf shape and fruit, but not the flower. Can you send me a sample? That will help quite a bit.

Q: What is Trimec? A brand name, or ingredient, liquid spray or granular product? I can't seem to find it in my local stores. (Wagner, S.D., e-mail)

A: Trimec is a proprietary product of the PBI Gordon Company, which has a Web site at where you can click on the Turf and Ornamentals section and get all the information you want on Trimec formulations. Basically Trimec is a broadleaf, postemergent weed killer that can be used selectively in turfgrass situations. They may be able to tell you where a local supplier is in your area.

Q: Last year I received a free packet of seeds labeled "Solanum guineese; Garden Huckleberry." The plants are beautiful with huge, dime-sized fruit that I would like to make jelly out of. My neighbor told me they were poison and a noxious weed. Is this true? Also, can a weed in the nightshade family cross-breed and make huckleberries poison? (Carrington, N.D.) 

A: Tell your neighbor that potatoes are poisonous if they are green, but not if they aren't green. The same is true of garden huckleberries. Unripe, they are poisonous, but when ripe, they are not. They will not spread like weeds unless you allow the fruit to drop; they are annuals and will be killed with a hard frost. There's nothing to worry about concerning cross breeding.

Q: I have questions regarding two problems. Problem No. 1 is something that is growing in our yard. Problem No. 2 is something that is taking over my sister's flower garden. Could you please let me know if these are plants that we should destroy and how we should go about doing it? (Cogswell, N.D.)

A: No.1 is crabgrass, an annual you can treat with a pre-emergence herbicide. Number 2 is Russian knapweed, a tough, persistent perennial that will require Trimec being applied a couple of times per year to eliminate from the lawn. Now is a good time to start.

Q: Could you identify the enclosed weed for me and tell me how to get rid of it? (Pelican Rapids, Minn.)

A: It is crabgrass. Apply any of the following products next spring when lilacs bloom: Acclaim, Dimension, or herbicides that contain DSMA, Dacthal, Betasan, Balan, pendimethalin, or Tupersan.

Q: I discovered a plant growing in one of my flower pots. It gets buds with yellow showing, but they never open. What is it? (Wishek, N.D.)

A: Your plant is known as velvetleaf, a weed that belongs to the Mallow family. The seed is viable for a long time, so keep it from producing any. The plant is a warm weather species and can get to more than 6 feet tall!

Q: I have a plant that I call Snow-on-the-Mountain, but my Ortho book says it's Euphorbia. I am wondering what the correct name is, and what is wrong with it. It looks like fungus to me. I also would like to know if you have any plans to offer the Master Gardener program in the Maddock area? (Maddock, N.D.)

A: Your plant is variegated bishop's weed, and it appears to have rust. Just cut it off or even mow it back, clean up the litter, and it will send up vigorous new shoots.

The Master Gardener program will begin in January 2000, but we haven't determined the sites in the state yet.

Q: We have a fairly large patch of strawberries, but have been getting few berries out of this patch. What type of fertilizer should we be using and how often? Also, what should we use for weed control? We also have a large patch of raspberries along the south side of our garage and we've always gotten quite a lot from them except this year. Is it possible that this patch is dying out? It is more than 10 years old and, we have never done anything with it except to cut out the dead canes. (Barnesville, Minn.)

A: Your strawberries may very likely have a virus disease, one of the symptoms of which is a yield reduction. They and the raspberries should be fertilized twice a year; once in the spring at initial growth or green-up, and again right after harvest. The material to use is 5-10-5 at about 10 to 15 pounds per 100 square feet. 

Raspberries just don't "die out" unless something is killing them. It be virus, root rot, cane cankers, anthracnose, cane borers etc. 

Both crops require constant attention to good management practices to be sustained productively. For example, the old mother strawberry plant should be tilled up each year, allowing the daughter plants to be more productive. The following year, those daughters are tilled and so forth.

Q: Can you tell me what weed is growing in my lawn? In the summer it matches the grass pretty well and now it looks dark and goes to seed. How can I stop it besides killing the whole lawn with Roundup. (e-mail)

A: The weed is crabgrass, an annual that is easily controlled with pre-emergent herbicides in the spring around the time lilacs bloom.

Q: I have a prominent weed in my lawn. What is it, and how can it be controlled? (Portland, N.D.)

A: Knotweed! Control it first by correcting the problem that allowed it to get established--compaction. Core aerate and power rake, then overseed (in mid-October) with a quality grass seed. Next spring if any of this stuff sprouts, catch it in the early seedling stage with a broadleaf herbicide.

Q: A weed has been rapidly spreading and taking over my entire lawn. Would you please tell me what it is and what spray I can use to kill it? (Page, N.D.)

A: It is the infamous Creeping Charlie, otherwise known in distinguished circles as Glechoma hederacea. This is a member of the notorious mint family which has a reputation of producing aggressive perennial characters. This one is no exception, as I'm sure you've discovered!

This is its most vulnerable time--the fall--so give it a recommended shot of Trimec to take it out (you may have to do it twice).

Q: I have a weed in my yard and was wondering if I can control it with 2,4-D or Weed-B-Gon. (Oberon, N.D.)

A: Your yard is sprouting oxalis. Yes, you can control it with 2,4-D or Weed-B-Gon. Expect to do repeat applications because this plant is a prolific seed producer. Work on getting your lawn in shape so this doesn't have a chance. Mow high and fertilize two times per year.

Q: A weed that grows in my yard seems to be spreading more every year. I've tried Ortho Weed-B-Gone, but it doesn't touch it. (Eureka, S.D.)

A: You have one of the toughest weeds to eliminate in the lawn—violets. They will need repeat applications of Trimec to take them out. This can be obtained from any garden center or garden supply store.

Q: What do you recommend for fighting weeds in my garden? (Lakota, N.D.)

A: Garden herbicides are most effective when they are applied to a cleanly cultivated area as a preplant or preemergence herbicide. Nothing controls all the weeds, so persistence is important. Try using clean mulch where necessary, in combination with these herbicides, and you'll at least have the satisfaction of knowing you're giving it your best shot.

Q: What is the best way to keep my raspberry patch weed free? Is it okay to use Round-Up on it? (Belcourt, N.D.)

A: Weed-free raspberries is a dream that will never come true. Reduced weed pressure can be realized through proper cultivation, mulches, and the proper use of herbicides like Roundup.

Here is what I would suggest:

1. Use shallow cultivation between rows to remove weeds.

2. Spot spray carefully any emerged weeds with Roundup

3. Seed a cover crop of creeping red fescue or Covar hard fescue at a rate of 80 to 100 pounds per acre (for quicker establishment, you may want to mix in come perennial ryegrass).

4. Fertilize at a rate of 60 to 80 pounds of nitrogen (N) per acre to keep the grass healthy, and mow it three or four times a year.

5. You may want to mix in some white clover (Trifolium repens) to supply some of the N.

6. Whatever you do, maintain about 3- to 4-foot strip of weed-free soil within the raspberry row. This can be achieved with organic mulches once the emerged weeds are under control.

7. Herbicides that are registered for weed control in raspberries are Casoron 4G (grassy weeds and some broadleaf pests like Canada thistle), Poast, Princep and Suflan. Roundup of course can be used any time active growth of weeds is taking place, but spray should not be allowed to drift into raspberry foliage.

Always be sure to follow label directions, as inappropriate timing of application can wipe out a crop.

Q: We bought a house in Fargo and with it inherited a flowerbed full of pigeongrass and a garden plot that became grassed over and essentially an extension of the lawn. I spaded the soil up last fall and this spring plan to take a tiller to it and then use Roundup. What would the proper timing be for these two treatments? Will one application of Roundup be sufficient? What kinds of vegetables and flowers can I plant after the Roundup? (Fargo, N.D)

A: Pigeongrass and other annual grasses can be effectively controlled with a material known as pendimethalin, commonly available on the retail garden market.

Roundup has no soil activity, so there is no waiting period. However, it is a good idea to wait until you are assured of a complete kill of the unwanted vegetation before working the soil up. This usually takes about seven to 10 days, depending on the weather.

Till as soon as the soil can be worked; then treat with Roundup when the weedy growth appears. Give it about 10 days to make a good showing. Generally, one treatment of Roundup will be sufficient, according to my definition. You will never be 100 percent free of weeds, so don't even hope for it.

Q: I have this weed spreading in my lawn very fast, and I would like to know what it is and how to get rid of it? (Freeman, S.D.)

A: Your sample, which was in a zip-loc bag with water, was half-rotted, but it appeared to be a type of yarrow that is quite aggressive. I'd suggest applications of a 3-way herbicide compound like Trimec. It may need repeat applications to get effective control.

Q: Could you please identify the enclosed weed and tell me what to spray to get rid of it? I also would like to know what to spray to get rid of the grass in my strawberry patch. (Erie, N.D.)

A: The sample you sent in was purslane, a prolific seed-producing annual that is best controlled with a preemergence herbicide like DEPA. Or, you can give up and cultivate it as a salad green.

If the quack grass is especially bad, you may want to dig it up and begin again. Refer to the extension publication "Weed Control in North Dakota Lawns" (H-1009).

Q: I have this weed spreading in my lawn very fast, and I would like to know what it is and how to get rid of it? (Freeman, S.D.)

A: Your sample, which was in a zip-loc bag with water, was half-rotted, but it appeared to be a type of yarrow that is quite aggressive. I'd suggest applications of a 3-way herbicide compound like Trimec. It may need repeat applications to get effective control.

Q. Can you tell me if there is any chemical spray that can be used to control Creeping Charlie that will not kill the lawn? Also control of night crawlers.

I enjoy your column and learning many things. Thank you. (Lake Park, Minn.)

A. A relatively new product for homeowners is Confront. It will control just about any broadleaf weed.

Night crawlers are controlled with an application of Sevin to control grubs. Follow label directions for grub control and about one-third of the night crawler population will also be controlled.

Refer to the enclosed circular, H-1009, "Weed Control in North Dakota Lawns," available to other readers by calling (701) 231-7882.

Q: Can I put a weed preventer (like Preen) on now in my flower bed? I have poppies that seed back every year. Will this prevent them from coming back? Also, how do you get rid of moles? I haven't had much luck trying to trap them. (Winner, S.D.)

A: You can apply Preen after the first of April and it shouldn't hurt the poppies. As for mole control, get rid of their food (grubs) and they will move on.

Q: There is prickly plant with big leaves growing 2 to 3 feet high in my raspberry patch. What is it? (Portland, N.D.)

A: I would say the plant is a currant (Ribes spp.) of some kind, but which one I'm not sure. Kill the plant off with a paint brush dipped in Roundup when it re-leafs this spring.

Q: What granular herbicide would you recommend for weed control around trees in yards? The trees have a rock bedding around them with railroad ties at the borders to keep grass out, but weeds are still a big problem. There are both hard wood and conifers in the yard. Price, of course, is a consideration. (Amidon, N.D.,e-mail)

A: Nothing works better and is safer for trees than Roundup. Just remember that it will kill anything green--green bark, green leaves--but Roundup is not soil active, so it will not be taken up by the roots. It is also comparatively economical.

Q: I have moss that's growing on the ground on the north side of my house. How do I kill it? Someone told me the only thing to do was to take the top layer of soil off, put new soil in it's place and then plant a shade grass. Is there anything else I could do? Like apply a fungicide? (LaMoure, N.D., e-mail)

A: Moss will likely form again. You need to improve the drainage of your soil and reduce the watering in that area. A site that supports moss is likely to not support grass too well. Try creeping red fescue, or rough bluegrass if the area is continually moist. The rough bluegrass is the best one for those conditions.

Q: Is there a simple or logical way to remove lichen on older gravestones? (Litchville, N.D.)

A: I would suggest a sandblaster. These portable tools are available for rent and do a good job of cleaning up old grave stones and iron work.

Q: I live across the street from a fertilizer plant and the carpeting on my front porch is covered with green moss. Someone told me it is caused by the fertilizer. If I install new carpeting will it happen again? (Kent, Minn.)

A: Most likely the moss is also encouraged by the weather conditions. If you can, and the moss isn’t too thick, scrape it off and wash down with a chlorine-bleach solution. The fertilizer dust helps in the development of the moss, but the continually moist conditions are the major cause. Getting new carpeting will temporarily solve the problem until the conditions build again for moss to develop.

Q: As a genealogist, I hope no one will take your advice to sand blast lichen from gravestones as this may damage the writing on the stones. A better solution is to use a brush and take care not to go down so far that the writing is damaged. Opening the tree shade up to let light on the stone will prevent lichen from forming in the first place. (e-mail)

A: Your advice is better than what I gave. Thank you! None of us want to lose that information on the gravestones, as it is often the only surviving record.

Q: We have a two-acre yard that we've been having problems with since we moved here two years ago. We have every weed imaginable and are at a loss as to how to control them. I was wondering if we could use Trimec to control ground ivy, dandelions, chickweed, quackgrass and all the other weeds. We planted 125 bare root trees this spring and don't want to damage them. We would like some type of universal weed control. (e-mail)

A: Sounds more like a job for Roundup than Trimec. Roundup will take out anything it touches that is green, while Trimec takes out only broadleaf plants (not grasses). Roundup also does not have any residual soil activity, so you can worry less about any negative effects on your tree plantings.

Q: I have a creeper that is impossible! With these wet years the conditions are encouraging to the plant. They tell me it is "creeping Charlie." I want to get rid of it, but I don’t want to kill the grass. What can I do? (Cresbard, S.D.)

A: In some cases you might be better off allowing the creeping Charlie to remain, especially in the shade and north side locations. If you are determined to get rid of this without killing the grass, I suggest using Trimec. It will take two or three applications or more over the next year, but it will do it, selectively. There are precautions with this product which need to be observed to keep from damaging surrounding plants. Otherwise, you can use Roundup which will kill everything off -- grass and weeds -- giving you the option to replant with grass seed.

Q. Could you tell me what kind of plant or weed this is? It grew by our house and I thought it might be parsley, but this year it has flowers and grew really tall and is going to seed. (Tripp, S.D.)

A: The plant was Queen Anne’s lace, or wild carrot. It is a good sod-busting weed with a nice deep tap root. Some people in the prairie cultivate it as a flowering perennial; in the east they consider it a weed . For your records, it is known as Dacus carota, and the seeds are valued by birds.

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