Questions on: Misc. Pests
Ron Smith, Horticulturist, NDSU Extension Service
Q: I found your very informative site on Google and thought maybe you could help us. Three years ago we found worms on a couple of low-growing evergreens. They were about an inch to 1 1/2 inches long. They are green, with black heads. They hung in a cluster of 10 to 40 and bobbed and weaved in unison (I assume in imitation of a blowing breeze). In just days they decimated a couple of adjacent trees/bushes. We wound up pruning the branches and drowning the worms. The worms went away for three years, but now they are back on a young pine tree. In just a few days, they ate half the needles. In a crunch, we used the only thing we had, which was Terro ant killer spray. It worked and they died on contact. We checked the original bush/tree they were on and they were back in force there, too. Any idea what they are? (Burnsville, Minn.)
A: They are sawfly larvae, which are ravenous feeders. Spraying with Sevin or whatever you have will do them in. They come and go, but you should monitor your evergreens to catch them in their initial stages before too much damage is done. There could be a second generation later in the summer, so keep a sharp eye out for them.
Q: I recently purchased an Aphelandra squarrosa from a local plant shop. Unfortunately, it has a lot of aphids and the bottom leaves are turning brown, shriveling up and dropping off. I'm trying to decide the best route to deal with the issue. There are some factors to take into consideration. I'm in a dorm room and have nowhere to put the plant for treatment, so the treatment has to be something that can be done inside. I'm leaving in a couple of months, so I will be giving away the plant to my roommate. I do not want to give her a problem plant that she has to hassle with. With that in mind, would it be better to try to treat it or just chuck it? What treatments are possible? (e-mail reference)
A: I'm half tempted to tell you to take the plant back to the shop that sold it to you, but you probably couldn't get away with it anyway. The best treatment for aphids under your conditions is to use an insecticidal soap. You need to make direct contact with the aphids for the material to work. You likely will have to do at least a couple of applications to bring the aphids under control. Aphids are a group of 4,400 species of small insects that feed on the phloem fluid of plants. Aphids reach a large population size very quickly. These reproductive characteristics allow aphids to quickly colonize, especially on indoor plants where there are no checks and balances from nature. If you are up to the battle, arm yourself with some insecticidal soap and begin attacking. This material kills by disrupting the structure and permeability of the cell membranes. In other words, the aphids will dehydrate or suffocate. Insecticidal soaps are the safest approach to controlling these and other soft-bodied insects because they do not contain organic solvents and have no residual affect. If you are not up to doing battle with this stubborn, stupid and prolific insect, then dump the plant!
Q: Last year there was a program on television on the preventive care for birch borers on two species of birch trees. We have one of each variety. Both are young trees. We wish to treat the soil around the tree to protect it. What is it that we put in the soil and surface around the tree? What dosage do we use and how far out from the trunk of the tree should we place it. We live in a small town, so I need to know the product name and where to buy it? Thanks for any help you can give us. (Burke, S.D.)
A: The product is Bayer Advanced Tree and Shrub Insect Control, which also is known as Merit insecticide. It is a soil drench that is poured around the base of the tree in early to mid-April. Explicit instructions are included with the insecticide. Be sure they are carefully followed. Any garden center tuned into the 21st century should have it available.
Q: The birds, mostly wrens and sparrows, love to sit on our porch railing. Their nests are in the shrubs surrounding the porch. The mess they leave on the indoor/outdoor carpet is a constant chore to keep clean. I have used mothballs in the landscaping to keep the cats out, which in turn keeps the birds off the porch. Is there anything, such as liquid mothballs, that can be sprayed on the porch railing to keep the birds from sitting there and doing their business on the floor of the porch? (e-mail reference)
A: First of all, mothballs, crystals or liquids, used in a landscape is considered an illegal use of a pesticide. It could result in a hefty fine being imposed on you. There are repellents you can use. Tanglefoot is a clear, sticky, Vaseline-type product that comes in a tube. Wearing protective gloves and using a caulking gun, spread the sticky goop where the birds roost. It annoys them to the point of finding another place to do their thing! Another tactic is to string piano wire along the rails at 2 or 4 inches in height. This will keep the birds from getting a comfortable grasp of the rails. Thiram is a product that is available as a stand-alone or mixed in a liquid and then sprayed on a surface. It has an obnoxious smell and will keep the birds from roosting, but also may keep you from using the porch. There is bird netting that you can string across the porch opening that will befuddle the birds. Some may get caught in it, necessitating you freeing them. In the meantime, the paniced cries from the bird should warn others to stay away.
A: Fruit flies are an annoyance and difficult to control once they get established. They breed where there is rotting or overripe fruit, slow drains or wet surfaces, such as around high-organic potting soil. The adults can be trapped on sticky trap surfaces. Clean up the rest of the environment and replace the potting soil with material that is faster draining.
Q: I have several plants in my house. I also now have these annoying little gnat-type pests flying around the house. I wonder if they come from one of my plants. These gnats resemble a fruit fly. I thought maybe it was from our Christmas tree, which we tossed out a week ago. I've checked the plants, but haven't noticed any of these bugs near the soil. Can one of my plants be the source of these gnats? Can you offer any advice? (e-mail reference)
A: Generally, these gnats or fruit flies will die during the winter months after the central heating system dries the air down to 10 percent or 15 percent. I would suggest getting some yellow sticky traps to collect these pests, which gradually will take them out of circulation and keep them from continually reproducing.
Q: I came across your Web site while doing some online research. I wanted to bring to your attention that it is a federal violation to use mothballs or ammonia for any wildlife control. Hope you can get the information corrected on your wildlife (and cat) control tips. I wrote an article about the use of mothballs and ammonia. Here is the article.
Mothballs for Critters? No Way!
Working in the nuisance wildlife control business allows me to discover some very strange methods that homeowners try when dealing with their problem animals. I could write a book on the bizarre concoctions and absolutely silly ideas I have seen, and it would be titled "How not to solve urban wildlife problems," as none of these ridiculous methods have any effectiveness. I would like to share a bit of information on one of the most popular, but not effective, methods that people will use when they try to "scare off" mice, rats, or other animals that may be in or around their homes. Mothballs. Besides the fact they do not work for anything other than moths, here are some things to keep in mind. Mothballs pose a serious health hazard for people, pets, and animals. It is a federal offense to use them for any type of animal control. If a chemical, poison or commercial product of any kind does not list the particular animal on the label, it is a federal and EPA violation to use it for that purpose (that includes ammonia). Besides the negative environmental impact, the danger to humans is a major concern. The label on mothballs mentions (if you look hard enough) that it is against the law to use the product for anything except control of moths in articles of clothing. Mothballs are a distinctive smelling, volatile solid used to repel moths. Mothballs, which are classified as a pesticide, may look like candy to a child. Mothballs are poisonous when eaten and seizures can develop in less than one hour. Mothballs contain 100 percent of either naphthalene or paradichlorobenzene. Both ingredients produce harmful effects when they enter your system through inhalation. Irritation to nose, throat and lungs, headache, confusion, excitement or depression, and liver and kidney damage can result from exposure to mothball vapors during a long period of time.
Mothballs containing naphthalene are of special concern because naphthalene can promote a breakdown of red blood cells resulting in hemolytic anemia. Hemolytic anemia in mild form may cause fatigue. In more severe cases, it can cause acute kidney failure. Young children are at particular risk. Poisonings have been reported following dressing infants in clothing that was stored with naphthalene mothballs, suggesting that absorption of naphthalene may occur through the skin. It is impossible to miss the "danger" warnings on the packaging, but people still toss them around their homes without thinking twice about it. The warning label on mothball products reads "avoid prolonged breathing of vapors." This label is at odds with the normal use of mothballs. By the very nature of their ingredients, mothballs give off strong odors (vapors you can smell). These vapors tend to fill the entire home, making it nearly impossible to avoid prolonged breathing of vapors unless you live outdoors. Health studies have determined that if you can smell the mothballs, the vapors are at dangerous levels to humans. The situation is complicated further when mothballs are placed in closets or rooms with poor ventilation because the vapors build to high concentrations. Vapors are absorbed by clothes, blankets and sheets, resulting in direct exposure when you are around these items. The vapors are "heavier" than air, so the dangerous vapors constantly "bleed" down through your home when using them in an attic. I can guarantee that everyone in the house will become violently ill before the squirrel, raccoons or bats move out. Don't be foolish enough to try this nonsense. If you wish to repel moths and other insects, cedar blocks or chips are just as effective, offering an ecofriendly and safe method. Sorry, they don't chase away critters. The only answer to critter control is to trap them and seal off the openings into the structure. Trapping or otherwise eliminating the problem animal simply opens up the site for the next one if the holes are not repaired. Exclusion is the only solution for animal problems. Please excuse my use of the following "technical" information, but it adds to the serious nature of this article.
Naphthalene, also known as tar camphor, is a white crystalline solid with a distinctive mothball odor. Naphthalene is available to the public as a pest repellent and frequently is contained in mothballs, mothflakes and toilet bowl deodorizers. Naphthalene can enter your system through inhalation, skin absorption, ingestion, and eye and skin contact. Headache, nausea, vomiting, abdominal pain, malaise, confusion, anemia and renal disease are typical symptoms of naphthalene exposure. Naphthalene may produce possible damage to eyes, liver, kidneys, skin, red blood cells and the central nervous system. Hemolytic anemia, caused by the breakdown of the red blood cells, has been reported following immediate and long-term exposure. In more severe cases, hemolytic anemia can cause acute kidney failure. Cataracts also have been reported in workers acutely exposed to naphthalene by inhalation and ingestion.
Paradichlorobenzene is a white, solid crystal with a wet, oily surface. It is volatile and gives off penetrating mothball-like odors. Paradichlorobenzene is commonly found in mothballs, moth crystals, and in diaper, toilet and room deodorizers. Inhalation may result in headache, swollen eyes, stuffy head, anorexia (loss of appetite), nausea, vomiting, and throat and eye irritation. With prolonged skin contact, allergies and skin irritation have been reported. Symptoms from ingestion include nausea, vomiting, diarrhea, liver and kidney damage, and methemoglobianemia (which interferes with the uptake of oxygen). Chronic exposures to very high levels of para-DCB can result in liver and kidney damage. The U.S. Department of Health and Human Services has concluded that para-DCB may be reasonably anticipated to be a carcinogen. The state of California has gone further and declared this compound to be a human carcinogen, although there is no direct evidence from human studies to indicate that this compound is a human carcinogen. These determinations were made based on the results of animals showing that long-term exposure resulted in cancer in treated laboratory animals. Also, other animal studies indicate the possibility of birth defects at high level exposures. I certainly hope sharing this information will promote a safer environment around your home. The simple fact is that mothballs do not solve your critter problem, but pose some serious health concerns for humans, pets and other wildlife. Outdoor use in and around your garden would produce very short-term benefits because the active ingredients vaporize very quickly outdoors. Besides being illegal to use for animals, mothballs are a poor choice from both health and environmental standpoints. (e-mail reference)
A: Thanks for the heads up. That information you mention being on the Web site is old, as well as wrong and is not given any more. I'll request our Webmaster, Dave Rice, purge any reference to this from the archives. Your article will appear in our local newspapers as well. Again, thanks for calling this to my attention. As an owner of three spoiled cats, I can't imagine doing anything that would be harmful to them.
Q: I have box elder bugs on my flowers. How can I kill them? I have been using Malathion Plus, but it seems like there are the same number of bugs the next time I look. I have tried spraying on the house, but the bugs still come in. I also have lady bugs or bean bugs and stripped flies. (Nome N.D.)
A: You are better off hiring a professional pest control company. The Malathion should be doing the job, but the company can lay something down that will last longer.
Q: This spring and summer I noticed small spots in our lawn where something was digging. I assumed it was skunks or raccoons. Yesterday my husband noticed a lot of damage in the neighbor’s yard. The sod is peeled back and the dirt underneath dug up. We live on a farm with four houses. No one is living in the neighbor’s house. Can skunks and raccoons cause this much damage and why? Is it easier to get rid of the animal doing the damage or the thing the animal is digging for? I don't want them to start attacking our lawn. Any insight you have on this situation would be greatly appreciated. (e-mail reference)
A: That is typical of skunk damage. They are looking for and probably finding grubs, the larval stage of scarab beetles. Get rid of the grubs with a soil insecticide and the skunks will go somewhere else. You also might try trapping the skunks (good luck!) and moving them elsewhere.
Q: What can a homeowner use to prevent white grubs in their garden? The homeowner’s potatoes have been chomped on by grubs. I also found the little buggers when I dug some of my potatoes. (Forman, N.D.)
A: Granular Sevin will do the trick. Use it next year at planting time.
Q: I had a lady call me about white or yellow butterflies in her garden. What can she use to get rid of them? She has tried garden powders, but they didn’t work. (e-mail reference)
A: The butterflies are laying eggs on the cabbage, broccoli, cauliflower and brussels sprouts. BT (Bacillus thuringiensis) sprays are effective at selectively controlling caterpillars. Sevin also can be used as a spray on the cabbage crop. If quick enough, she also can take the butterflies out of the air. This species is so aggressive at attacking the brassaia family that it becomes very discouraging to attempt to grow any without getting into a lot of insecticide use. Nasturtiums and old-fashioned marigolds are supposed to disguise the scent characteristic of this family, but to date, I have not had any success with this approach.
Q: We seem to have a terrible epidemic of worms in our yard. How often can Sevin be applied? We believe that it will take at least a couple of applications. We decided not to water the lawn this summer. Will this help us get rid of the worms? Thank you for your help. (e-mail reference)
A: Hot and dry soil will do a number on the earthworm population. The grub application of Sevin also will control them somewhat. The applications should be made during a two- to three- year period. For effective control, do the application in the spring or fall.
Q: I’m trying to find a way to keep my dog out of my flower garden. The dog likes to dig a hole and then lie there. If there are some plants in his way, he scratches them out of his way and continues to dig a hole. (Langdon, N.D.)
A: Try Liquid Fence sprayed around the garden, especially where he likes to lie down. It keeps bunnies and deer away, so it might work on dogs. However, I sometimes wonder if any odor is strong enough to be offensive to dogs!
Q: A lady in our county is wondering what she can use to control worms in her onions and cabbage. With Diazinon off the market, can Malathion or Sevin be used on the cabbage to control worms? Can Dipel, Biotrol or Thuracide be used on the onion maggots? (e-mail reference)
A: Sevin is the better choice for onion maggots and can be used to control cabbage moth larvae. Dipel can be used on cabbage, but needs to be applied frequently and is slower acting.
Q: I am looking for something that will drive away robins without harming them. I have looked on the Web and seen some devices, but I was hoping there was some sort of home remedy that would stop them from perching. The robins have found a particularly favorite spot and I was hoping that we could keep them away. Thanks! (e-mail reference)
A: You make this a very tough question to answer if you don't want any devices. I only can make the same suggestion that I would for keeping woodpeckers out of trees. Spread some Tanglefoot on the branches where they typically perch. This is very sticky stuff that birds abhor getting on their feet. It doesn't hurt the birds, but the Tanglefoot does irritate them to the point where they will move to another tree. This is not a home remedy, but close to it.
Q: I have two Australian shepherd dogs. Urine builds up during the winter, so I have a beautiful, burned lawn come spring. Is there anything I can put on the grass to reverse the effects other than digging up the spots and planting new grass? (Bismarck, N.D.)
A: I wish I knew something that would solve the problem or could invent something. If I could invent something, I would be a very rich man! I'm sorry, but other than immediately diluting the urine with generous amounts of water, there is nothing that I know of that will take care of the problem.
Q: I cut back two plants and brought them in for the winter. The plants are doing great, but they have some very small, black flies that resemble fruit flies. These are mostly in the dirt. What can I do to get rid of them? (e-mail reference)
A: The flies could be fungus gnats or fruit flies. Spray the flies with a houseplant insect spray while they are active. Several products are available on the market. If they persist, try repotting with fresh, pasteurized or sterilized potting soil. They are more of an annoyance than a threat to the plants.
Q: My house is infested with boxelder bugs this winter. I have been killing them with a mixture of water and dish soap. I cut down the tree that had the bugs. Is there anything else I can do to get rid of the bugs? If not, will they continue to enter my house in future years? (e-mail reference)
A: Boxelder bug infestations seem to be on the rise because of our mild winter. I would encourage you to hire a professional exterminator. The exterminator can place a protective barrier around your house to keep them at bay. This pest should disappear with the tree removed, but I've seen where they have congregated where no boxelder trees are nearby. Only time will tell.
Q: I read with interest your reply to the party from Kindred who was having problems with raccoons raiding the sweet corn in their garden. In the reply, you said they might try live trapping the raccoons, but felt they were too smart to fall for that. You have offered me good advice in the past, so perhaps the time has come for me to offer you some in exchange. Beginning four years ago, I had big troubles with raccoons. Lights didn’t deter them and radios just supplied dance music for a 2 a.m. snack! With the garden only 150 feet from the house, a bird cannon would scare me more than the raccoons, so that was out! The next year I decided to fix their wagon. I bought an electric fence and watered the soil to insulate the ground. I cut the grass down to an inch high and kept it there with a string trimmer. I ran a wire 8 inches above the ground and then leaned back to enjoy the coon’s surprise! However, I was the one surprised because it did not slow the coon traffic. I then added another wire 16 inches off the ground and a bit later a grounded wire between the two hot wires at 12 inches. To my great surprise, the raccoons acted as though the fence wasn’t there. I then thought the fence was defective, so I put my finger on the wire and quickly dismissed that thought! Roasting ear stage was ending, but the coons had harvested more than I had! I then learned that there was a federal wildlife agent stationed at the little town of McLeod, about 25 miles east of Lisbon. He said we should try to catch them in box traps. At the time, I felt much as you did, that they were too smart to fall for that trick. The agent had two traps, so he set them up for me and showed me how to reset them if I caught any raccoons. I soon trapped three of them before they quit eating my corn. I had to return his traps, so I bought three of my own last year. I soon caught them by the dozen! I even caught four coons in three traps one night; two were in one of the traps. The size of the trap is 11 inches by 11 inches and 33 inches deep. The next smaller trap is too small. This year I had corn pulled down by coons twice, about two weeks apart. Each time I had a coon in the trap, so concluded that I had the guilty party! Raccoons definitely can be caught using box traps. In fact, it’s the only way I had any success. The agent advised that I bait them with eggs or canned cat food, but I’ve come up with a better way to bait the trap. I have my wife collect all the drippings from the griddle when she fries bacon. I then bought a new pump oilcan. Coons locate the bait by scent and bacon fat odor carries farther than anything else and is not lost during a rain. I drip a trail for 2 to 3 feet outside the trap and stick the spout through the welded wire of the trap at the far end where the trigger is located. (Nome, N.D.)
A: Thanks for an interesting and entertaining story on coon trapping! Glad to know what works!
Q: I’m hoping you can help me with a problem I’ve never seen before. My daughter and I were outside looking at her cocoon (we found a giant green caterpillar in a cocoon). I told her it soon was going to be a moth. She wondered if it was the same type as the one she pointed to lying on the ground. As I looked at the moth on the ground, I saw some bees attacking it. The moth was alive, but partially eaten. I didn’t think bees ate other insects. (e-mail reference)
A: Bees don’t, so what you saw had to be members of the wasp family, Vesper spp. They eat other insects, especially as the days get shorter and we get closer to winter. This is a good opportunity to remind you and your daughter to be careful with open cans or bottles of pop, damp toweling or ripe fruit lying on the ground or meat sandwiches because the wasps are attracted to such things. Wasps have been known to venture into cans of pop to the painful surprise of the drinker!
Q: We have an organic garden with an earwig problem. I’m told a mixture of water and soap can be sprayed on plants that will kill earwigs, but not plants. What mixture should I use? Do you have any other suggestions? (e-mail reference)
A: Don’t try it! Purchase some insecticidal soap and use that instead. It is formulated to not damage plant material. You might be lucky one time and unlucky another because the fatty acid chain changes with each new batch of material produced. Besides, you need to hit the insect directly to be effective with this material. Earwigs do very little damage to plants. As an organic gardener, I’m a little surprised that you don’t know that their major source of food is other insects, especially aphids. You can trap and dispose of them by rolling up moistened newspapers if you consider them a pest, which they can be if they get into your home!
Q: I have had a problem with raccoons all summer. They ate some things in my garden (which is fenced), but then moved on to my garage to clean out the cat food every night. We have outside cats that go away for days at a time, so I like to leave food out for them, but the raccoons have quite an appetite! Does anything short of lead poisoning work for raccoons? I did find that planting zucchini, pumpkins and squash around my sweet corn did well at keeping the raccoons away from the corn. They must not like prickly vines. (Kindred, N.D.)
A: Zucchini keeping raccoons at bay? That is possibly the best use I have heard of for zucchini!
I was going to suggest “Liquid Fence” because it smells gross. I imagine it also tastes bad, but I don’t know if it tastes bad enough to keep raccoons away. You might try live trapping the raccoons to see if that works, but I think they’re too smart to fall for that! Thanks for the tip. I might write a grant proposal to see if, under controlled conditions, the zucchini plantings actually keep the coons away! In your case, it might be that they were just full of cat food, so corn on top of that lost its appeal!
Q: I have noticed in my yard that in at least two locations there is a trail that has no grass growing on it. The trail leads to a golf ball sized-hole running under my patio and through some landscaping. The trail is about two feet long and about an inch to an inch and a half wide. Do you have any idea what might cause this kind of trail and what I could do to prevent it? (e-mail reference)
A: This sounds like ground squirrels are taking up residency on your property. Get a garden hose and force some water down the hole. They almost always have more than one exit, so have someone else on the lookout for a head or two to pop out of the ground somewhere else and go scooting away. You can live trap them or call in an exterminator to take care of them.
Q: How can I get rid of potato bugs? No matter what kind of spray I use, I can’t get rid of them. The bugs I have (I think) are called Colorado potato beetles. (e-mail reference)
A: The larval stage of the potato beetle will be the most vulnerable to Bt, which is an organically approved material. When sprayed on the foliage and eaten, it will cause the insect, at this stage, to become sick and die. This will interrupt the reproductive cycle. Application after a rain event is necessary and any new growth would require a reapplication. Reapplication is needed throughout the season as the bacterial material breaks down in the sunlight. I have found that the combination of hand picking and spraying with Bt formulations is the most effective at controlling this pest.
Q: I have a vegetable garden that is swarming with roly-poly (or pill) bugs. What little I’ve read about them says they are beneficial to a garden because they clean up rotting vegetation, but there are so many of them that I can’t imagine they won’t damage my crop. When I pull a radish, I see dozens of them surrounding the root. Can I use Sevin to kill them? What do you recommend? (Wall, S.D.)
A: Sevin will take care of them and not be detrimental to your vegetable garden.
Q: Can mealybugs live in the soil? I’m wondering if they are surviving because I’m not treating the soil. Also, you had previously mentioned a systemic treatment. Is that still an option? (e-mail reference)
A: Mealybugs have been known to lay eggs on containers, benches and other nonplant surfaces, so you may be right in that these little bounders are coming from the container or the soil. Repot with fresh soil and probably a new, free-draining pot. Systemics should be the last resort. They are usually very toxic, so I don’t like getting them into the plant, let alone having them handled by anyone.
Q: I think I have Asian beetles (they look like ladybugs) in one of my flower gardens. I was told to plant rosemary to get rid of them. Does this really help? I had hundreds of them against the side of my garage when I was cleaning out the flower garden last fall. I really would appreciate any info as to how to get rid of these bugs. (e-mail reference)
A: I don’t know of anything that will get rid of the beetles outside of normal attrition. I have not heard that rosemary works to get rid of them. Look at it this way; your garden should be free of aphids because of the beetles.
Q: I have black aphids on the leaves of my bamboo plant. What can I do to get rid of the aphids before they destroy my plant? I also have aphids on my white arrowhead plant. (e-mail reference)
A: There is a material known as Insecticidal Soap that will take care of the problem through direct contact. It is not harmful to the plant or you. It is available from almost any garden supply outlet.
Q: This winter, we attracted some very beautiful woodpeckers to our birdfeeders. Unfortunately, one of the larger woodpeckers has dug a couple of large holes in the center branch of my crabapple tree. Is there a product that I can use to seal the branch? When is the best time to apply it, winter or spring? (e-mail reference)
A: I would suggest using Tanglefoot, which is a sticky material that comes in a can or a large toothpaste-type tube. Smear it around the area of the woodpecker’s activity because they hate to get their feet sticky, so they will move to another tree or territory. As for the hole the woodpecker has made, there isn’t much that can be done except to allow it to heal naturally. There is nothing you can do except to cut back any jagged bark to help facilitate healing.
Q: I have microscopic white bugs (they do not fly) that live in the soil of my plant. It was outside last summer, but has been inside since it turned cold. The little pests seem to surface when I water the plant. So far, I have tried spraying it with a household pesticide and herbicidal soap. A friend recommended that I water it with soapy water. I used regular dish soap without phosphates. I filled the pot completely with the soapy water and then allowed the water to drain. I waited an hour and then continued to flush out the rest of the soapy water. I was told that the mites living the soil breathe through their skin, so the soapy water would coat them and suffocate them. I have done this twice and assumed it worked, but when I watered the plant a week later, the mites had returned. Should I get rid of the soil? (e-mail reference)
A: You have me stumped. It could be a form of root aphid or root weevil. The bugs obviously are impervious to your attempts to bring them under control. You didn’t indicate if there was any apparent damage to your plant. Hibiscus tolerates being handled and repotted quite well, so get rid of the soil. Use fresh material that has been sterilized or pasteurized and is in an unbroken bag. Be sure to wash the roots in tepid water and scour the container or pot. Give the plant plenty of water. Avoid damaging the roots as much as possible during the process.
Q: I see little things flying around that appear to be gnats. Is there a possibility that these are coming from my plants? If so, what type of damage could these flying bugs do and what should I do to control them? (e-mail reference)
A: Those gnats could be adult fruit flies or fungus gnats. The adults do little more than annoy us, but the larva can cause root damage, although the damage is usually minimal. Generally, the dry air from our central heating systems during the winter will kill them, unless the environment around the plants is very moist or humid. If they continue to annoy you, purchase some Insecticidal Soap, which can be purchased at any garden supply store, to knock them down.
Q: I brought my plants into the house late in September. I also brought in a million tiny black flies. Now I cannot get rid of them. I sprayed the plants with Raid House and Garden, but only lightly. My husband is allergic to the carrier in aerosols so I cannot use it again. The bodies of these flies are about a sixteenth of an inch or maybe a bit longer. Is there any way to get rid of them? I am using Aeroxon Window Fly Catchers (a sticky tape that goes on the windows). It works well, but is not nearly enough. I hope you can help because I do not want to throw the plants out to get rid of the flies. (Huron, S.D.)
A: The flies are probably fungus gnats or fruit flies that took hold in your soil during the summer. You can repot the plants in fresh soil. Clean the containers completely in hot, soapy water and rinse thoroughly. Also, rinse the plants in tepid water. If any critters remain, get ahold of Schultz’s Insecticidal Soap or Fungicide 3. This is a neem extract product, so your husband’s allergies should not be activated. Generally, these pests die from the dryness as the central heating unit is activated with the arrival of cold weather. It’s a good idea to try to get them under control before then, if possible.
Q: What can be done to improve a yard that is horribly bumpy from earthworms? (Valley City, N.D.)
A: A temporary fix is to power-rake the bumps or roll them down with a ballast roller. A more permanent fix is to treat the lawn for grubs, which in turn impact the earthworms by killing off about a third of the population. Roll or power-rake the lawn after that.
Q: We are considering getting a dog, but have a large crabapple tree in our back yard. We do not know the type, but we’re concerned the dog may get sick if it eats the apples. (e-mail reference)
A: I have had dogs, so I know they will eat just about anything that they shouldn’t, but I’ve never had one that ate crabapples or any fruit for that matter. If the dog does get sick, it will be minor and temporary and, unless the dog has Swiss cheese for brains, it wouldn’t make the same mistake again. Get your dog and enjoy the company it will provide. You will benefit in the long run.
Q: Do you know what kind of worm/larvae is about two centimeters long and completely orange? It appears they only come out at night. They seem to live in or around spruce trees and anything made out of spruce. (e-mail reference)
A: They could be sawflies. Pick some off, set them up in rubbing alcohol and then take them to a university entomologist for identification and control.
Q: A lady purchased a product at a seed store in Mandan that is supposed to be good for controlling little black bugs (flea beetles?) in her garden. The product is called Diatomaceous Earth, Crawling Insect Killer and is made by Natural Guard. Now she is wondering if this product is okay to use directly on the plants in her garden or if it should just be used on the soil. Can you tell me anything about this product? The bag’s label says nothing about avoiding garden vegetables during application. (Dickinson, N.D.)
A: She can use Diatomaceous Earth anywhere she wants. It is an excellent, mild abrasive on soft-bodied insects. Placing it in the soil around her plants as well as on them, if she can keep it from falling off, will prevent soft-bodied insects from setting up home. She would be controlling the larval stage of the flea beetle as well as any others. It kills by lacerating the soft body tissue and causing death by dehydration.
Q: Woodpeckers have pecked holes in the ash trees that I planted along the boulevard. Is there a way I can keep the woodpeckers away or get rid of whatever is in the tree that the birds are so keen on? Also, I have an area up on Devils Lake that has full exposure to the elements in the summer and winter. What kind of trees would survive that type of area? I thought about a silver maple or a linden, but someone said the lack of protection would do them in and to not waste my money or time. (Jamestown, N.D.)
A: Woodpeckers and sapsuckers (same family of birds) don’t like sticky feet, so the approach that seems to work for most people is to get some Tanglefoot and spread it around the area the birds are attracted to. I would go for the shelterbelt trees such as boxelders, green ash, hackberry, Japanese tree lilacs and possibly poplars.
Q: I may have a problem with my silver weeping willow. This spring it didn't leaf out as strongly as past years. Last year I noticed small holes just into the bark. Because of the distinctive pattern, there was no doubt in my mind the holes were caused by a yellowbellied sapsucker. Can this bird kill the willow? I now see the bird in the tree all the time. Should I get out the 4-10 shotgun or do you have any suggestion? (e-mail reference)
A: Keep the shotgun for something more important and legal than killing a yellowbellied sapsucker. I doubt the bird will kill the tree; however his persistence indicates that he has found a good hunting ground for food. While their primary source is the sap, that sap also attracts insects which the sapsucker consumes as well. For control, tactile repellents such as Tanglefoot, Bird Stop and Roost-No-More are quite effective in some cases, but are messy for the applicator to use. Some success has been reported using propane cannons or electronically generated explosions that vary in timing. If those options don’t work and the tree continues to decline, a permit to kill the bird can be obtained from the Animal Control Division of the USDA. The sapsucker is a migratory species and is important in controlling unwanted insect pests such as borers. The bird is protected under the Migratory Bird Treaty Act of 1918.
Q: I planted some bulbs last April. They weren’t growing so I dug them up and found a bunch of small little white worms in them. What are they? Some of the bulbs are now starting to grow, but very slowly. (e-mail reference)
A: Some type of insect laid eggs in the bulbs. The eggs hatched and the worms are now in the larval (feeding) stage. They will eventually consume the bulb to the extent that it will not produce much of a flower, if at all. Your best bet is to dispose of them.
Q: A farm homeowner has a serious problem with white grubs. They have been treating the lawn with Sevin. Will the grub problem just continue if they don't treat every acre of their farm yard? They have a large area to mow. (Cando, N.D.)
A: The typical lawn grub goes through cycles. Believe it or not, the cycle depends on weather and natural control forces such as disease, predatory insects, birds and mammals. I would advise treating only the worst areas with Sevin. Spray the entire area with a biological agent such as Bt for long range control. Every lawn has some grub activity.
Q: Could you please give me the recipe for the pepper spray you say helps keep rabbits away from plants? How often should I use it? (e-mail reference)
A: There are many versions, so don't think of it as an exact science. Take four to six jalapeno or habanera peppers, put them in a blender and mix in enough water to make slurry. Pass the slurry through a cheese cloth to get rid of the residue and add it to a quart of water in a spray bottle. Add a drop or two of Elmer's glue, shake and apply directly on the plants. Be sure to wear rubber gloves when you are handling the peppers and the solution. Whatever you do, don't rub your eyes or any other parts of your body while making this concoction.
Q: Upon returning from the south, we found burrowing in our lawn and a great deal of dead grass. We suspect it is the work of skunks as this happened to our neighbor several years ago. We live on a lake in a rural area. I purchased Carbary some time ago but did not apply it. Would an application of Carbary be helpful at this time? It appears the mischief is done at night. Would illuminating the area at night be of any advantage? We have a global arborvitae that animals have chewed off a good one and a half feet from the bottom leaves. I’ve never had that happen before. (Pickerel Lake, S.D.)
A: Sorry, I don't know what "Carbary" is. Keeping snacking animals at bay usually works by using hot pepper spray. You’ll need to reapply it after rainy periods. Skunks and other rooting animals are looking for grubs so your lawn is a good supper for them. You could get your lawn treated with Bt which is a biological insecticide that would slowly reduce the grub population. It would not pose a hazard to other wildlife in the area or upset the soil's ecosystem.
Q: Sorry, but I spelled the chemical wrong. It is spelled Carbaryl (1-natchthyl N-methylcarabamate). Maybe you are familiar with it.
A: Carbary1 is more popularly known as Sevin. You can use it to control grubs but be sure to water it in.
Q: I have a new residence with a sodded lawn. The grass was in excellent shape going into last winter. As the snow melted, I noticed a lot of damage on the grass. The grass has been chewed off and bunched up in several locations. As the snow was melting, I noticed a mouse like creature along the side of a snow bank. Can you help identify the nature of the problem and the creature causing the problem? Will the lawn recover? What can be done to eliminate the creatures? (Moorhead, Minn.)
A: What you are seeing is a vole, a mouse-like creature that tunnels under the snow through the grass leaving little trails or pathways. Don't feel you are the only person with this problem. Voles tunnel through many lawns, including mine, every winter. Rake the lawn with a leaf rake this spring; then give it a light application of fertilizer after the first mowing. The beauty of Kentucky bluegrass is its high ability to recover from such treatment along with compaction, insect and disease damage. I wouldn’t worry about trying to eliminate the little pests. They disappear during the summer months because of predators or shyness. This coming fall, cut your grass about one inch shorter than you did during the summer. Also, clean up any leaf residue and debris that could provide cover. You can try poisoning and trapping, but I would rather let nature take care of things unless it gets out of hand.
Q: What do you recommend in place of diazinon for wireworm control in garden potatoes? (E-mail reference)
A: Set up a trap by scooping out a couple of low areas in the soil and placing some pieces of potato in the hole. Cover the holes with a board to collect swarms of wireworms. Collect the infested potatoes and dump them in a pail of soapy water. Another tactic is to improve your drainage because wireworms tend to gravitate toward moist soil. As a final alternative, get some granular Sevin and place it in the soil as the potatoes are planted. Plant some buckwheat as a cover crop after the harvest and turn it the following spring. The buckwheat will act as an insect repellent and soil conditioner.
Q: I recently read a letter to you from a Jamestown resident with concerns about spotted flies in his attic. I would greatly appreciate it if you could send me the same information because these flies are a pain in the neck. Also, do you have any suggestions on how to prevent them, or at least help control them? (Jamestown, N.D.)
A: The flies enter the house in the fall of the year as the temperatures begin to drop close to freezing. If the temperature doesn’t drop too low where they have settled in, they can go into a dormant or resting stage and become active again when the temperature goes up. Or, they can lay eggs and when the temperature goes up sufficiently, the eggs hatch and eventually morph into pesky flies. To correct this problem for next year, go over the exterior of the house and seal up the smallest openings with caulking. To take care of the problem for now, the sticky strips that hang from ceilings or rafters will do an excellent job without using pesticides. Also, the botanical pesticide, pyrethrum, is a good knockdown product to control flies. It can be found anywhere that garden or houseplant products are sold.
Q: Where did the flies come from that invaded my attic this fall and winter? They were never around until about a year or two ago. They are dark gray with white spots and like to live in windows or in a bright area. How do they get in and why are they alive in winter? How do I control them or prevent them from hatching? Where do they live and produce in the summer? (Jamestown, N.D.)
A: These pests are known as cluster flies, which could be any number of species. I am enclosing a publication written by Jeffery Hahn, entomologist at the University of Minnesota. Most likely you will have to employ a professional exterminator to get effective control.
Q: We've been invaded by attic flies this fall and winter. Can you tell us where they might be getting into the house and how to control them? (Ashley, N.D.)
A: I am not sure I know what you mean by attic flies but there are a couple of remedies you might consider. Flies enter the house through the smallest openings, lay eggs and when the conditions are right, emerge as adult flies. If they are what I think, the usual winter household temperatures will kill them. If not, then get some sticky fly strips. They do an excellent job of catching most flies and don't pollute the environment or hurt anyone else. Flies of any kind are extremely susceptible to pyrethrum based products, which are available in just about any garden store. You can spray them as you see them and eventually win the war. These characters that get into the house in fall can also go into a rest or dormant state when the temperature drops. If the low temperatures do not kill them off, they become active pests when the temperature rises on high-light-intensity days, which we have been having lately.
Q: A neighbor has fruit flies in her house that she can’t get rid of. She has tried to go to the source but has no rotten fruits, vegetables, potatoes, onions, etc. She did have some squash go bad on her but threw it out. What can she do? (Linton, N.D.)
A: Run Drano or some other drain sanitizer down all the household drains, especially the kitchen drain, including the disposal. She also needs to get some sticky tape and hang it where the populations are highest. She should be able to get it at any farm supply store. It used to be called "flypaper" which my grandfather had hanging all over his grocery store when I was a kid. Finally, get an aerosol that contains pyrethrins (that can be used indoors for flying insects) and spray them. Their life cycle is about 7 days, so a two-week period of intensive assault should do the trick.
Q: About a month ago I purchased two houseplants from a local retailer. They are thriving except some leaf edges have been turning brown. While repotting, I noticed little, almost translucent colored worms in the soil. I should have done the smart thing and tossed both plants but I really like them. I removed as much soil as I could, almost down to bare root, and transplanted them. Can I add an insecticide to the soil? Also, what were those little bugs? (Glyndon, Minn.)
A: They could be the larval stage of springtails or some other insect that feed on organic matter. I would advise against adding any insecticide to the soil. Try to water with low salt water as much as possible and do not over fertilize. Generally the burning or browning on leaf edges is the result of too much salt or poor drainage. The container should be free draining, and excess water that pours through the container bottom should be dumped within a 1/2 hour after watering. As long as you repotted with sterile or pasteurized soil, there shouldn't be a problem.
Q: Do you have any suggestions for killing earwigs without chemicals? We are trying to keep an organic garden. I have heard soapy water might work. What concentration of soap to water should I use? (E-mail reference)
A: Purchase some insecticidal soap. It is safe for organic gardening. Simply follow the directions on the container.
Q: The grackles have nearly ruined my marigolds. They peck away and leave flowers all over the ground and sidewalk. Any ideas on how to make these pests leave my marigolds alone? (Fargo, N.D.)
A: Grackles are the mischievous teenagers of the bird world. Spray your plants with pepper spray. Also, tie aluminum strips to small stakes throughout your marigold planting. The pepper will burn their tongues and the aluminum strips will scare them. Once they are driven away they usually won’t return.
Q: A lady has flies gathering on her porch where there is shade and are "leaving their mark" up the side of the house. What kind of residual spray can be used to control house flies outside? Do those sprays have any affect on steel siding such as discoloring? What else would you suggest for controlling flies? It is not a sanitation issue as it is a very clean yard but it seems the flies just like the shade! (Amidon, N.D.)
A: Malathion is the typical fly control. I don’t know if it leaves a permanent stain so I would suggest trying it on an inconspicuous area first.
Q: I would like to try to grow Niger thistle for bird feed in a corner of my home garden and at my son's home in Alberta. What are your recommendations in this regard? ( Victoria, B.C., Canada)
A: I'd say go for it and not pay out valuable Canadian dollars to the imported material that I'm sure is saturating your market as it is ours. There is a short-season cultivar known as early bird that we have successfully grown in the Northern Plains - specifically in the Carrington, Langdon, and Minot Research and Extension Centers. The crop was productive at all sites even when a delayed planting (June 13) took place at Carrington. The seeding rates were experimented with and it was found that the 9-pounds per acre rate consistently outproduced the 3- and 6-pound per acre rates. The yields ranged from as low as 300 pounds per acre to as high as 700 pounds. So, if you get something successfully going there, you might have yourself a small economic nest-egg!
Q: I had fruit flies on some peaches last fall. The peaches are gone but the fruit flies aren't. I think they are living in some of my house plants. Any idea how to get rid of them without killing the plants? (West Fargo, N.D.)
A: Fruit flies are harmless but pesky! They need a moist environment to survive, so your houseplants are a logical choice. Look at the garbage disposal unit on your sink to see if they are originating from there. They are very vulnerable to insecticidal soap spray which is not harmful to us or the plants. Safer is one company that markets such a product and is usually available anywhere garden supplies are sold.
Q: I have a beautiful Hope philodendron. I have been noticing what appears to be very tiny light-colored worms around the area where the plant sits. They are usually dead by the time I notice them. Can you shed any light on the subject? (E-mail reference)
A: They could be any number of critters, but I would guess that you are looking at the remains of earwigs or centipedes. Both are organic matter feeders and do not directly cause harm to the plant. If you are concerned, you can try a solution of insecticidal soap and use it as a soak but not as a spray. Pour the soap into the potting soil around your plant. This is a harmless material to plants and warm-blooded animals when used properly, but is effective at killing off soft-body insects or their larvae (which yours may be) by dehydration.
Q: Some of us like to keep some beavers. We chicken wire our trees at a minimum of 48 inches. Be sure to check it regularly. We also spray cayenne pepper powder around and on the tree in real active areas. It’s time consuming and labor intensive - but effective. We have 1 1/3 miles of creek trees we protect this way. It's the best method we've come up with to co-exist with the beaver. Plant or encourage cattails as beavers seem to eat the roots quite voraciously. (Letcher, SD)
A: Thanks for the excellent suggestions!
Q: To the lady with the beaver problem. She should use 36 inch hardware cloth, 3/4 to 1 inch, wrapped loosely around the trees so it will expand with the tree. That should save her trees if she doesn't live by running water. They will kill acres of trees if they dam running water. What they eat isn't too bad. In two years she will be glad to get rid of them. The guy that's going to move trees should learn to root prune first so the tree will make a root ball. It sure helps in sand or sandy loam. (Bemidji, MN)
A: Thank you for your common sense advice. I'm sure all of the readers will appreciate it.
Q: I had a conversation with a lady this morning about beaver damage to her trees. I tried to explain to her the best control method is to have the problem beaver removed by trapping, but she didn't want to hear about it. She is intent on spraying her trees with paint or something paint- like to deter feeding. I didn't think this was a viable option as beaver will eat bark from ground level to 30- to 36- inches up the tree. Plus, how do you go out and spray every vulnerable tree? I think I have her talked out of that, but she still wants to spray all the trees that were damaged. Any suggestions as to type of paint, or if she should even do it? (Hettinger, N.D.)
A: Spraying trees the beaver has fed upon is of no use. The tree will heal itself, if at all, much faster without any tree wound dressing. I am afraid that her only option is to trap them. They are a protected species so she should contact a Game and Fish Department person to see what it will take to rid her property of them.
Q: We bought a live Christmas tree last year, an aleppo pine. It's not the prettiest tree in the world, but it's our defacto tree for the holidays. It grew about 6 inches this year and seems to be doing well, except for masses of mealy bugs on the main stem and on the newer growth. I soaked the whole tree in Neem oil spray a couple of weeks ago. Is there anything else I can do that is more effective. This tree is potted and is about 5 feet tall. (E-mail reference)
A: Time to try something with a little more horsepower, although I think the Neem should do the trick. I suggest that you try insecticidal soap because it is less toxic and should also do the job. Resort to Malathion if that doesn’t work. If that fails, give up! They're too tough but one of the alternatives should work.
Q: Every year my alyssum has some infestation by small black hopping bugs, but this year seems to be particularly bad. What is the name of these bugs? Why are there so many this year? I have powered with Sevin-10, which helps, but doesn't eradiate as in past years. The ground below the flowers is black with the insects. (Sykeston N.D.)
A: This is likely some species of flea beetle that has fallen in love with your alyssum and is developing a resistance to the Sevin insecticide. Unfortunately these adult beetles have the ability to overwinter under leaf litter and other debris to begin feeding and laying eggs the next year for another generation. The first step in control is to clean up everything possible this fall, removing or limiting any hiding places for them. Next, using a selection of insecticides will help; alternate Sevin with Malathion, then Orthene, etc. This keeps the beetles from building up resistance to one insecticide. These characters are a problem once they get established, so don't expect the battle to be an easy one.
Q: A local gardener has a severe infestation of blister beetles, both black and gray ones, on her tomatoes. She just sprayed last evening with diazinon. Will this take care of these guys? Also, she consistently has large numbers of slugs each year. She uses a slug bait once they appear but was wondering about options to eliminate them completely. (Hettinger, N.D.)
A: It should control the blister beetles, but I wouldn't spray anything I would want to eat with diazinon. Sevin is the better choice, and is labeled for tomatoes. Slugs love litter and hiding places like rocks, boards, and low, leafy vegetation. Eliminate as much of that as possible, and that will help. Also, turn over the garden soil in the fall to expose the critters trying to nestle into something that will protect them.
Q: Enclosed is a leaf from my neighbor’s tree. I am wondering what the disease is and if it can be sprayed and with what. I am afraid our trees will be next, but as of yet, our trees are okay. (Breckenridge, Minn.)
A: You and your neighbor have nothing to worry about. What you are seeing is callus tissue growth from the early season feeding of mites. Their damage is largely cosmetic, not destructive, and requires no spraying on you or your neighbor’s part. Next season they may be gone, or they may be back, and if they return, you still have nothing to worry about. Technically this malady is called spindle gall, caused by eriophyd mites. It is an interesting effect, so enjoy!
Q: I just read Hortiscope and it reminded me to ask if you have ever addressed the new requirements of all applicators to be commercially certified. We are getting calls from homeowners for recommendations of lawn and garden applicators and I believe most agents have taken the position that they won't recommend an uncertified operator. Here in Devils Lake we currently have no certified applicators, but I still tell callers not to hire anyone but a certified applicator. Just thought your column would be a good place to give people a heads up. (Devils Lake, N.D.)
A: Following are the certification requirements. We want them certified, not in jail!
Commercial Pesticide Certification: A commercial applicator, dealer, or consultant is "any person who engages in commercial application, sale, or recommendation of pesticides or commercial employment of devices." To become certified, a commercial applicator, dealer, or consultant must pay the certification fee, pass an open-book monitored core and category exam(s), and demonstrate proof of financial responsibility or have the proof of financial responsibility waived.
What follows are descriptions of the major categories of certification for non-agricultural use:
- Home, Industrial, and Institutional Pest Control--includes applications, recommendations, and merchandising of pesticides in, on, or around food handling establishments, human dwellings, public or private institutions, warehouses, grain elevators, and any other structures or adjacent area, for the control of pests.
- Ornamental and Turf Pest Control--includes commercial applications, recommendations, and merchandising of pesticides to control pests in the production and maintenance of ornamental trees, shrubs, flowers, and turf.
- Public Health Pest Control--includes commercial applications, recommendations, and merchandising by state, federal, or other government employees, working under government contract, using pesticides in public health programs for the management and control of pests having medical and public health impacts. Including municipal and other area wide mosquito control programs.
- Right-of-Way--applications, recommendations, and merchandising of pesticides to control pests in the maintenance of public roads, electric power lines, pipelines, railways, right of ways, parking lots, or other similar areas.
- Greenhouse--includes applications, recommendations, and merchandising of pesticides to control pests in a greenhouse.
Materials for the exams are provided by the NDSU Extension Service Pesticide Program. To obtain these materials, contact your county extension office, the NDSU Extension Pesticide Program, or request materials from the NDSU Extension Pesticide Program web page at: http://ndsupesticide.org
Training sessions are not required, but are extremely helpful for passing the certification exam(s). The NDSU Extension Pesticide Program conducts statewide training sessions each winter/spring. Information on the training sessions is mailed annually to all commercial pesticide certificate holders. For further information contact your local NDSU county extension office, NDSU Extension Pesticide Program, or access the NDSU Extension Pesticide Program web page http://ndsupesticide.org
Once a person has met the certification requirements, a certificate is issued to the individual in the appropriate category. The card has the applicant's North Dakota pesticide Identification number, name and address of certificate holder, category(s) certified, and expiration date of each certified category. Certifications are valid for three years. All categories expire on April 1 of the year indicated on the card.
Q: My sister-in-law has a philodendron that is beautiful and full, but the other day she noticed that there are tiny silver bugs crawling all over the dirt. She has not seen them anywhere else in her house. What are these and are they harmful to the plant? What can she do to get rid of them? (E-mail reference)
A: They are probably the larval stage of fungus gnats or they could be earwigs. If they appear to be confined to the soil mass and show no interest in the aerial part of the plant, you can water the plant with a malathion solution. But first, get the plant out of doors or the odor will make everyone sick! A less-toxic approach would be to take everything outside and repot it in fresh soil after washing the roots completely with clear water.
Q: I live in south Moorhead with an empty dirt field across the street. I have a problem for the past few weeks with ladybugs in my house along the south window. I have a south front door and picture window and there are ladybugs along the floor and window sill every day. I spray and vacuum and they keep coming. Can you give me any advice? (Moorhead, Minn.)
A: Just put up with it or fight it the best way you can. The mild winter has led to an abundance of these helpers, many of which will starve to death due to a lack of sufficient food.
Q: Just reading some information on the Internet on Trimec. I have ground ivy and it is in my perennials. Perennials include hostas, day lily, tulips, iris, mums, etc. Can I apply Trimec on my perennials and not kill them? (Fergus Falls, Minn.)
A: Trimec will very effectively take out your perennials in addition to the ground ivy. You can use Roundup with caution, covering the perennials as you spray around them.
Q: My back yard faces a large field. All last summer we constantly battled a daily tick problem with our two outside dogs. This spring we are once again starting to remove them on a daily basis. We want to treat our lawn area with something that would deter the pests and help with the problem but need something recommended that would not harm our dogs in any way. Can you recommend what to use? (Minot, N.D.)
A: Ticks in a suburban setting are a little unusual. I assume you are keeping your lawn mowed.
What you need to do is contact a professional exterminator to come out and treat your yard. Some lawn care companies have competent personnel on board that can carry out such missions. This is something I would not recommend that you do yourself. A professional with the right equipment and formulation will do a much better job.
Q: I think it was in your column where I read that these striped-winged flies come from the ground. I have never had them as bad as this year. We put an addition onto our home last summer and I wonder if breaking up the ground for the footings made the flies more abundant. If the flies come from the ground, is there anything that can be done to the area around the house this summer to cut down on the population? Maybe it is because of our mild winter, but they are terrible. Any suggestions? (Hitchcock, S.D.)
A: You need to employ a professional exterminator at this point. Home remedies will not work. The flies are the result of mild winter weather causing a premature hatching.
Q: I am wondering what you can tell me about these pesky little flies. I have heard them referred to as brown flies, brown spotted and just spotted. It seems they are indigenous to old houses, but this year they have not gone away as they usually do. I am not from this part of the country so they are new to me. Are they just a nuisance or are they carriers of yucky things as are the regular flies. (E-mail reference)
A: These are just harmless pests. They are particularly pesky this year because of the early and long mild winter we've had. You can do battle with them via sticky tapes, insecticidal soap sprays, and any sprays for interiors that contain pyrethrins. Their life cycle is short, but their reproductive capacity is high, so persistence is necessary.
Q: What can a person use on Indian meal worms in a large quantity of garlic (in cold storage at about 45 degrees)? We need a product that will not have a residue. (Hettinger, N.D.)
A: There is nothing that is registered for this purpose that I can find. Best thing to do is throw them out into the snow for 24 hours to kill the worms and bring the bulbs back in. Otherwise the infested bulbs must be dumped.
Q: I am wondering how to get rid of fruit flies. Fly spray doesn't phase them. (Linton, N.D.)
A: Go to the source. This is usually over-ripe fruit or a sink garbage disposal that has some decaying vegetable or fruit matter in it. Dispose of the fruit and clean the disposal. Fruit flies are quite vulnerable to insecticidal soap but have a fantastic breeding cycle that will continue unless the source can be located and disposed of.
Q: How do you get rid of those pesky little fly or gnats that come in with your plants when you bring them in from outside? Mine have been bothering me all winter. (Redfield, S.D.)
A: Those gnats and fruit flies can be a problem at times, driving the owner crazy and doing little harm to the plants directly. A couple of remedies: you can use the no-pest strips to get rid of them. Simply enclose the plants in a clean garbage bag with the strip overnight and "poof," they are gone. Or, fog them with insecticidal soap (available anywhere houseplant supplies are sold) or a neem-containing product. The soap or need will take several attacks to accomplish what one treatment with the first suggestion will do.
Q: Do you or any of your readers know how to get rid of white flies on house plants organically? If not organically, is there a systemic chemical you put in the soil so they can eat themselves to death? (Brookings, S.D.)
A: Use insecticidal soap solution as a dip on the houseplants that you can treat that way. If you cannot dip a plant, use the soap as a spray. It is organically approved and insects cannot build resistance to it like they can with the inorganic chemicals. Another material is known as Neem, derived from the tree of the same name. It is found in "Schultz's Expert Fungicide 3" which acts as an insecticide and miticide as well as a fungicide. This works very well in providing control.
Another way (not organically approved) is to use a no-pest strip. Put the houseplants in a large plastic trash bag along with the strip and tie it shut for 24 hours. That usually does the trick for good. I would use this as a backup where you cannot get satisfactory control with the insecticidal soap or the Neem. Good luck! They are terrible pests. It used to be that when they got into tomato greenhouses the only way you could control them was to strip everything out of the house and let it lay cropless for a season through heat and cold, as well as an insecticide treatment.
Q: I am enclosing two bugs, which I find in my home a few times a year. I don’t know if you identify bugs, but if you can tell me what they are or how to get rid of them, I would appreciate it. (Woonsocket, S.D.)
A: According to NDSU extension entomologist, Phil Glogoza, they are pseudo scorpions. They are not true insects, but are insect predators, holding their prey with the pinchers they have on their bodies. They are usually associated with damp places, wood piles, bark, etc. They are not harmful to humans.
Q: You mentioned spraying with Bt for potato bugs. You also said it would not leave any residue on the tubers. Does dusting the potato plants with Sevin leave residue on the tubers? Is it absorbed through the leaves? (Bowdon, N.D.)
A: Neither the Bt (aka Dipel) nor Sevin leave any residue on the tubers.
Q: For the last two or three weeks something has been digging up our lawn at night ( I mean MAJOR). We have not seen anything, so we know it is during the night. We have heard Canada geese flying nearby during the day and we are assuming that they are coming in at night digging for grubs or something. The holes are 2-4 inches across and also that deep, plus, of course, mud is thrown around the holes making a very messy looking yard. Do you think that it is geese, and what can we do about it? Do we need to get rid of the worms, and how? ( LaMoure, N.D.)
A: I have never heard of geese being that hard up for food. I would tend to think it might be a skunk, raccoon, or mole. You might try applying a soil insecticide like Sevin in the granular form to kill off the grubs and reduce the earthworm population to see if that brings about an improvement.
Q: You have given a couple suggestions for treatment of black knot disease. One is pruning out the knots and spraying the tree with a lime-sulfur mix. In one place it refers to the timing as a dormant application and another leaves the impression it is during the growing season. Which method is correct, or are they both acceptable? You also mentioned the use of a product called Cavalier, which is evidently applied during the growing season. (E-mail reference, Billings, Mont.)
A: Glad you asked! I didn't mean to imply that lime-sulfur could be used when the trees were in leaf. It should NOT. That's why Cavalier is suggested at this time. Also, the pruning should take place when the tree is dormant in the early spring, then follow up with the lime-sulfur application.
Q: I have three questions regarding leaves of some of my flowers: My delphinium leaves as well as a few other perennials have a kind of mottled yellow pattern in them. The plants have all been fertilized and the yellowing is a part of the entire leaf ( very light). Another plant showing the same type of mottling is rose mallow (Malva). What should I do to get the leaves healthy? I would like to keep the iris leaves looking nice this summer. Some are already turning brown at the tips or have brown spots. What should I spray to prevent this? What do I use to prevent hollyhock rust? Last year really devastated the hollyhocks and most leaves died. (E-mail reference)
A: The mottled leaves sound like the "etchings" of a very small insect larvae called the leaf miner. Generally their destruction is only cosmetic and not lethal. No spray is necessary as they have already done their damage and moved on. Some decline in appearance is to be expected in iris once the blooming has passed. You can spray with an all-purpose fungicide like Bordeaux mixture or Daconil 2787, along with a fertilization with Miracle-Gro. Spray your hollyhocks with a fungicide like Daconil 2787 (chlorothalonil) at the first sign of rust development. Avoid splashing water on the foliage, remove all plant debris this fall, keep the area weed-free as much as possible.
Q: We have an area in our lawn with a severe infestation of Japanese beetles. We would prefer to use biological controls rather than chemicals, particularly since we have planted a large number of flowers and shrubs in the last two years that will attract butterflies and bees. We are trying to restore our outside environment without harming beneficials. I have ordered some beneficial nematodes to help battle the beetles. However, I am wondering what you can tell me about the effectiveness of milky spore disease, and whether you know of any sources where this can be purchased, since I haven't been able to locate any. Thank you for your assistance! (E-mail reference, Jamestown, N.D.)
A: You don't have Japanese beetles. You have a type of Scarab beetle, called May or June beetles. Fortunately, Japanese beetles cannot survive our winters. Try the "Gardens Alive" catalog. Milky spore disease is listed on page 5. Call them at (812) 537-8650.
Q: I have a problem with worms getting into my onions and radishes and destroying them. Is there anything I can do? (Edgeley, N.D.)
A: Radish and onion maggots can be controlled a number of ways: Don’t plant either crop close together or in rows. Mix heaping teaspoonfuls of wood ashes 1 inch into the soil where the radishes and onions will be growing. Spread an agricultural barrier (Remay or fleece) over the seeded area.
Q: Last fall we noticed that our lawn had bulges all over with small holes. After a rain there are a lot of angle worms or earthworms on the sidewalk and patio. What remedy should we be using? (Carrington, N.D.)
A: Treat the lawn with Sevin, following directions on the label for grub control. A single application will control about one-third of the population.
Q: I have a large raspberry patch that is being plagued with a black bug. Can you tell me what I need to do to get rid of them? I have customers waiting for these berries, so I don’t want to lose them. (Frazee, Minn.)
A: The sap beetle or picnic beetle can be a pest to berry growers. I would suggest control with insecticidal soap as soon as the berries begin to color or the beetles appear. This is an organic approved spray that is harmless to warm-blooded animals. This way, your clientele don’t need to be concerned with any toxic residues.
Q: I've recently noticed that a small swarm of flies has invaded my spider plant. They are small and seem to have settled more on the soil than the leaves, but there isn't any visible leaf damage. Any ideas on how I can rid myself of these pests? (E-mail reference)
A: The swarm of flies are likely what are called "fungus gnats." They are more pest than pestilence. If you can obtain some insecticidal soap in a "pump" bottle, simply spray when you see them swarming. It will take several applications to get them under control, but this material is harmless to us and your plant, so you don't have to worry about over-use.
Q: My mother is having a terrible problem with lady bugs in her house this winter. The upstairs bedroom on the southeast end is filled with them. Everyday she can sweep up around 80 of them. We have tried spraying them with Tempo. That kills them, but there is always a new batch coming in. What is causing this and is there any way to get rid of them? She thinks they might have come in with her outside plants as she winters over lots of plants in that room. (E-mail reference, Perham, Minn.)
A: Ouch! Spraying lady bugs. I hate to see it happen, but if they are pests, there is nothing you can do about it. I suppose it is better than having them starve. They are probably hatching or becoming activated with the warmer weather. If you will recall, last fall there was a very high population of them across our region. When the weather started to turn cold, many migrated into homes, looking for places to hibernate for the winter. Now they are waking up and there is no food for them. Not much you can do about their peskiness except what you have been doing, unless it is to use a vacuum to pick them up.
Q: We have a problem with striped flies, or some call them attic flies. I have also heard they thrive or come in with plants, but we don't have any plants in our house. Any suggestions on where they come from or how to get rid of them? We just tried "Tempo" and that seems to help but doesn't take care of the problem completely. (E-mail reference, Jamestown, N.D.)
A: I'm willing to bet that they are fruit flies that are starting to hatch with the warming weather. They are attracted to rotting wood, fruit waste, or compost, and of course are not active when it is so cold. Tempo is an effective insecticide for this problem, but as far as I know, it is listed for commercial use only. Be careful. Fill up sinks and tubs with hot water with about a 10 percent chlorine bleach solution and let it go down the drain. This will "sanitize" those sites and possibly eliminate the problem. Other than that, all I can recommend is patience. They will eventually move outside as the weather warms.
Q: Could you tell me what to use to spray plum trees while in bloom and bearing fruit, etc. to prevent the little bug sting that is on the fruit once it bears? (E-mail reference, Georgia)
A: Sevin is an acceptable insecticide to use at petal-fall. This insecticide is extremely toxic to bees, so spray only when the bees are inactive, early morning or late evening. You will want to spray again when the foliage is fully expanded, and again about 20 to 30 days later. Good sanitation -- picking up the dropped fruit -- will also help control this pest. The insect you are trying to control is known as the plum curculio and likely has two generations in your part of the country.
Q: I have a problem with small light-colored and black bugs on some of our indoor plants. They seem to congregate on the upper leaves and buds before they flower. We tried using alcohol, but with little effect. They seem to be like an aphid , only smaller than the ones I've seen in the alfalfa fields. (E-mail reference, Adrien, N.D.)
A: Your bugs may still be aphids, a common pest on houseplants at this time of year. They are very vulnerable to insecticidal soap, so what I suggest is to cover the top of the plant container with aluminum foil, make up a solution of the insecticidal soap in a large enough bucket, dip the entire plant in, and swirl around. For plants that are too large for this, spray the insecticidal soap directly on the plant, being sure to cover the undersides and leaf axils. Expect to make a couple of applications.
Q: Do boxelder bugs need boxelder trees to survive? (E-mail reference, Mott, N.D.)
A: The boxelder bug, also known as Leptocoris trivittatus, is found where ever the boxelder tree (Acer negudo, also known as Manitoba maple) is grown, especially the pistillate (or female, seed-bearing) forms. They feed on the developing seeds, leaves, and tender twigs. They will also feed occasionally on other maples and ash trees. These attractive insects are known mostly for their nuisance qualities because of their habit of congregating in large numbers near or in homes as winter comes on, seeking out places to hibernate. They emerge the following spring as the weather warms, migrating to one of the host plants, with the boxelder maple being the preferred one. Certainly the landscape would be improved with the removal of the boxelder tree or trees and replacement with something else that is not a known host of this insect. Without a suitable host, their numbers would decrease to the point of non-annoyance.
Q: I have a large 8-foot schefflera and two diffenbachia plants that have little black bugs I have been unable to get rid of. The leaves look sickly and are gradually turning yellow and then dropping. My next option will be to cut them back and hope that breaks the cycle. The bugs have been laying eggs that you can see. I hate to cut back the schefflera but it’s apparently gradually dying, and due to the size and location of this plant I do not want to spray any chemicals. How would you go about getting rid of the bugs or cutting back the plants. (E-mail reference)
A: You have to make a decision as to whether or not the plant is worth saving. If the damage is too extensive for the plant to recover and be an asset, you are better off dumping it. If the decision is made to keep the plant, then I'd suggest getting one of those "No-Pest" strips and a large trash bag. Place the strip on the soil in the pot and put the bag over the entire plant, tying it to the base of the container. Keep it like that for 48 hours, then uncover and dispose of the strip properly. Wear protective (disposable) gloves when handling the strip. Another alternative is to spray the plant with insecticidal soap. This is a special long-chain fatty acid that kills on contact, so complete coverage is necessary. This is completely safe to use indoors around humans and pets. It still may be a good option for you to do some trimming on the worst areas of your plant.
Q: I have a customer who is having problems with small, white nematodes in his tomato fruits. He is quite sure this is a nematode as they are just big enough to see and worm-like in appearance. Also, this guy is a retired entomologist, who did most of his work in the area of beetles, but is quite sure this is a nematode.
Have you heard of this being a problem anywhere else? How can he control this pest and keep his garden produce safe to eat? This is a relatively new garden site and would be difficult to move to another location. (Bottineau, N.D., e-mail)
A: With all due respect to the retired entomologist, I really do not believe they are nematodes for two reasons. First, I have never seen one that is visible to the naked eye. And second, they are generally not fruit attackers but prefer instead to work on the root system.
If he insists that they are nematodes, I am not going to argue with him, only suggest that he interplant his tomatoes with plants that serve as a nematicide. The best one, based on research and its ready availability, is the African marigold, which produces oxygen radicals that block steps in nematode metabolism.
My bet is that he is seeing the larvae of the click beetle--young wireworms. It is unusual for them to be after tomatoes, but they are common pests on potatoes, which are in the same family.
Tell your client to clean the garden well of any debris this spring, turn the soil over early and stake the tomatoes to keep the fruit from contacting the soil. All of this should help, no matter what it is that is going after his tomatoes!
Q: When does sunscald occur on shrubs such as blueberries, Saskatoons and currants? What can we do to protect the plants from this damage? Also, what can you tell me about what and when to spray to keep currants etc. from having worms in them? (Westhope, N.D., e-mail)
A: These shrubs are generally not prone to sunscald, which usually occurs on thin-barked trees such as apples or pears when they are young, and on the southwest side of the tree. Protection is generally achieved by painting with whitewash or wrapping the trunk with cloth. It occurs when the sun hits the dark colored bark and raises the temperature at that location to 50 F or 60 F or higher--and the air temperature is still below freezing. When the sun goes down, the cell tissue ruptures at that site and sunscald occurs.
As for your insect question, spray with Sevin when the shrubs are in flower. Keep in mind that Sevin is toxic to bees, so spray at a time when they are not active--either in the early morning or evening. Spray again right after blossom drop.
Q: While paging through some new garden catalogs, I read that fig trees can be grown in pots, then moved inside for the winter. Will this really work? That is, will the tree actually produce figs? What variety would be best? And what kind of care--fertilizing, "rest" during winter etc.--would it need? (My husband loves fresh figs and would be thrilled to grow his own.
Also in the catalogs, I saw an ad for a product called "Sluggo," which is advertised as an organic slug bait that is nontoxic to pets. The active ingredient is iron phosphate. I'd like to try it, but it's fairly expensive, so I wonder if you've heard any reports on it.
Finally, I should tell you that I'm the person who wrote late last summer with the hornets in the compost pile. You had some spray recommendations, but I finally broke down and called a service, and I'm glad I did. The service guy removed a nest in the pile the size of a softball. I doubt I would have had the nerve! (Bismarck, N.D., e-mail)
A: I have not heard of moving figs inside to get them to produce. I did know an Italian/American gardener when I was living in upstate New York who successfully grew figs that bore fruit by planting them against a wall that faced the sun most of the day. When winter came, he would carefully cut the branches back, and wrap the top part of the plant with water proof paper and shredded newspapers. He would then dig a trench along the side of the trees and lay them down, covering them with topsoil.
I have no experience or data with iron phosphate or the Sluggo you refer to for slug control. I cannot give you any judgement on its effectiveness.
I, too, am glad that you called a service to remove the wasp nest! I have been stung by those characters and the thought of that many being there makes my skin crawl!
Q: This past summer we have experienced for the first time some very unusual hard lumps in our yard. It appears to be something in the ground pushing up the dirt, which creates a very hard raised area. The dirt area that is pushed up is about 2 to 4 inches in diameter. They are easily felt when walking around on the lawn. There are many of them, and they cover a large area in our neighborhood. Would you have any idea what this could be and is there anything we could do next spring to prevent more of these? (Kulm, N.D.)
A: You very likely have a mole problem. They are subterranean feeders on soil insects such as grubs. They generally leave the area once the insect problem has been eliminated.
Moles are fairly good underground architects. They have a molehill which is formed when their excavation activities require the disposal of the soil. They have a feeding runway that you are experiencing, which runs right below the soil surface and is generally used only once. They also have a nest and permanent tunnel, which is a foot or more below the soil.
There is a chance the moles will not be active next season on your property. If they are still active, the easiest way is to flush the molehill and runways with water, which kills them by drowning. Or, you can capture them in a live trap and transport them somewhere else. Another lethal way is via a scissor-type trap. Also, employing tactics to control the grub population in your lawn would be an excellent deterrent for mole control.
Q: Can you help me to identify an insect? They seem to be damaging the early blossoms of my lilies, dahlias, hollyhock andm several others, causing them not to blossom at all. I found some newly hatched insects. They were a dark-brown, crawling mass, but they did not consume the leaf on which they had been laid. The adult insect seems to be about an inch long, a red-gold-brown color, and the body is in three sections. The bugs buzz quite noticeably, but they have not actually tried to sting me. Please help me to identify these, and how can I get rid of them? (e-mail reference)
A: Your description of the insect indicates to me that it may be a sawfly, as they hatch in masses like you describe. Sevin is labeled for their use. This has a very low mammalian toxicity, so it is relatively safe. You can also spray your deciduous plants next spring before leaf-out with dormant oil to kill any overwintering eggs.
Q: There are many spots throughout the south side of the house that have dead grass (large and small patches). A friend of mine said that we have grub worms under the grass and that is what is killing it. Is that right? What do you think it is and what can I use to restore the grass? (Fort Ransom, N.D.)
A: The only way to be certain of a diagnosis like that is to peel the grass back around the leading edge of dead patches of grass. I have not seen grubs as the cause of dead grass for the past several years. In most instances it has been a disease like pythium, Necrotic ring spot or one of the snow molds.
Q: I have wireworms in my house really bad. The fall or late summer and early spring months seem to be the worst time for them. They are all over the basement and are now coming onto the main floor. What can I do to get rid of them? I have tried spraying around the outside of my basement with malathion and have used diazanon, but neither seems to help. (Holabird, S.D.)
A: If you have this kind of problem, you need a professional exterminator. Wireworms are the larval stage of click beetles and are heavy feeders on potatoes, bulbs, seeds, etc. They are attracted to damp environments.
Get someone who is licensed and registered to apply pesticides in and around human residences. Diazanon is one of the insecticides suggested for their control, but unless it is properly applied, as it should be by a professional exterminator, it will only have limited effectiveness.
Q: I have a bush that appears as if it is being attacked by two different pests. One is a small caterpillar that forms a small compact tent, and the second pest almost looks like a tiny slug. Are they different stages of the same insect? What are they and how do I control them? (New Town, N.D.)
A: You are seeing the second generation of "pear slugs," which are not slugs at all, but the larval stage of sawflies, which are slightly larger than the standard housefly. Right now, cut off all affected branches on your cotoneaster and burn them. Next spring after leaf-out, spray with carbaryl (Sevin) or malathion. Repeat in 10 to 14 days. That should solve the problem.
Q: Our concord grapes have these little white bugs on them. How to I get rid of them? (Montpelier, N.D.)
A: The white insects are likely mealybugs, a piercing, sucking type that in high enough numbers can debilitate plants. The flying ones could possibly be flying ants--going after the honeydew secreted by the mealybugs. While there are effective natural parasites, you cannot afford the time at this point, or you will lose your crop. I suggest a spray with Sevin, making sure you have covered undersides of the leaves.
Q: The local cemetery has grubs in it and the racoons and skunks dig for them and are damaging the grass. What can we use to get rid of the grubs? (Wheaton, N.D.)
A: Grubs can be controlled by using Sevin or diazinon. Apply now, and water in. Repeat next spring when the grass has begun active growth.
Q. Enclosed are a few more of the "dotted" flies that have been bothering us. Can you identify these and tell us how to get rid of them? (Litchville, N.D.)
A. The insect samples arrived in good form this time, and were identified by entomologist Denise Olson as picture-wing flies. They are only pests, the larval stage feeds on decaying organic matter. They are likely coming in through window openings, cracks in walls, or as you come and go into and out of the house, if the entryway is near any kind of refuse pile.
Knock down household sprays are suggested.
Q. Can you tell me how to get the birds to stop eating half of the apples off of my trees? (McVille, N.D.)
A. A couple of suggestions: try "scare balloons," that are available where most garden supplies are sold or try netting the trees before the apples ripen.
Q: Can you tell me what kind of beetle this is? I found it when I was cleaning up the fallen apples in my yard. It is a small gray and red beetle with black spots. Are they harmful and what should I do to get rid of them? (Aberdeen, S.D.)
A: You had one of many species ladybird beetles. These unique insects are beneficial to us in both stages of their lives—the larval and adult. In the larval stage, it is a voracious feeder on aphids, and the adult continues that habit, expanding the eating palate to other plant-destructive insects.
Most likely this adult has laid some eggs that will hatch next year and help control aphid and other plant-destructive insect populations.
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: We are having trouble with skunks and need to know if there is a plant to ward them off. (e-mail)
A: I know of no plants. The only way to control skunks is to fence them out of the area you want protected with a chicken or rabbit wire fence. They are members of the weasel family and are constantly looking for food, such as spilled garbage, grubs, slugs etc. Skunks can also be trapped live, something that we have tried. But who is going to approach the trap to move them? You can't hire me! Remember, while the striped skunk is not a protected species, the spotted skunk is. If you live far enough away from residential areas, you may have to resort to shooting the striped animals, which are potential carriers of rabies. Be careful, no matter what you choose to do.
Q: Last year I had a problem with worms (wireworms, I think) in my potato patch drilling holes in them. How can I get rid of them organically? Will lime have any effect on the wireworms? Do you think they will be back this year? Also, can potatoes and sweet corn be planted side by side? (Tappen, N.D., e-mail)
A: I would suggest using Bordeaux moisture, which is an organically acceptable combination of copper sulfate and hydrated lime. It provides both insecticidal and fungicidal protection. I would dust the potato seed prior to planting and dust around the planting hole as well.
Q: Last year our lawn was full of grubs. They were even in the gardens. The lawn had about five big areas where the grass was brown and dead. We treated it with diazinon granules and this spring the grass came back really nice, so we thought the problem was solved. Wrong. I dug up a new garden and found lots and lots of grubs--some near the top and others about 5 or 6 inches down. What can we do to get rid of them? (Ashley, N.D., e-mail)
A: Grubs are not easily wiped out. While diazinon will work somewhat, a better treatment would be Bacillus popilliae (Bp) a microbial biological control that creates what is known as milky-spore disease. This is a material you spread over the lawn and garden area. Bp is perfectly harmless to beneficial insects, as well as us humans, and it kills by making the grub sick when it eats the spores. They die and their decaying bodies help to redistribute the spores in the soil. Usually one application does the trick, but in your case you may want to make an application now and another again in the early fall.
Q: My daughter and family who live in Ft. Madison, Iowa, have a problem with moles. They have tried numerous ideas such as hosing them out with water, chewing gum and hair wrapped around moth crystals. Is there a solution to getting rid of them? They seem to make new runs and move all over the property and to the neighbors. (East Grand Forks, Minn.)
A: If they are sure it is mole damage, then their food source--grubs mostly--need to be eliminated. Applications of an insecticide like diazinon will control the grubs and consequently mole activity. More common in the Midwest are pocket gophers. Their have widely varying food sources: roots, seeds, tubers and grasses. A common way to distinguish the difference between moles and gophers is to note the shape of their mounds. A gopher’s mound is fan-shaped with an off-set plug or hole, and an indentation in its circumference. A mole’s hill is circular with the plug at its center. With either burrower, steps for eliminating are basically the same: one, establishing physical barriers (welded wire mesh) buried where their activity is persistent; two, flooding the runs and when the varmints appear, dispatching with a shovel; three, trapping; and four, poisoning with carbon monoxide from a lawnmower engine.
Q: We have been battling grubs in our lawn for years with diazinon, but we cannot seem to get the upper hand. Recently, you mentioned Bacillus popillie (Bp). I have checked with greenhouses in Bismarck, but no on has heard of it. Do you have a brand name or company from which it can be ordered? I don’t like using too many insecticides because I am afraid of contaminating my well. (Napoleon, N.D.)
A: I’m afraid my previous information wasn’t 100 percent accurate. The Bp is effective against Japanese beetle grubs but not the white grubs (June beetles) that we have in North Dakota. The best bet, unfortunately, still appears to be insecticides. Timing is critical for good control, with the best being in the spring with the first mowing of the grass. Apply the product and water the insecticide in well. Repeat this for about three years, and you should pretty much have the white grub population under control.
Q: How do I go about encouraging ground wasps to leave? (E-mail reference, LaMoure, N.D.)
A: You are dealing with an animal that resists encouragement to move out. They will repay most amateurish efforts with a volley of stings and bites. So, unless you know what you are doing, you are better off letting a pest control service remove them. Otherwise, here are some suggestions:
1. Trapping - there is what as known as a Seabright trap that is for temporary use, and an IPC trap that is for longer term use. Wasps have been known to escape from each, so handling these traps filled with wasps should be done with caution.
2. Nest destruction or removal. Caution is emphasized here, as a careless action can result in many unpleasant stings. This requires that the nest be located and approached after sundown when the wasps are all back inside. Protective clothing is strongly suggested. Often, chemicals are used to kill the inhabitants before destruction or removal takes place. A pyrethrin/rotenone aerosol is used, and is sold under the commercial name of "Wasp-Stopper." Sevin can also be used for the same purpose.
3. Vacuuming. A professional company locates the nest and literally vacuums them out of the nest into a tank. Often, they are then frozen and sold to venom collection companies.
Q: A lady lives in an old house where wasps have found entry. The problem is that her grand daughter is highly sensitive to pesticides--a little sniff and it is a deep resting period. What would be some possible means of capturing the wasps? I suggested some fly tape sticky things, and possibly purchasing some mouse sticky traps to catch them. Do you know of a way of making a bait station that will attract them? (E-mail reference, Mott, N.D.)
A: Wasps in a home (assuming they have nested there) are nothing for amateurs to mess with. A professional exterminator is needed to get rid of them. Other than pesticides, once the nest is located, the exterminator will use a vacuum to suck them into a bag that is then placed in a freezer. The dead wasps are sold to venom preparation companies. This touchy task requires two people who are experienced at being around angry buzzing insects bent on stinging the daylights out of their attackers. Suffice it to say, proper protective clothing needs to be worn. They should also locate the nest and destroy it, since there could be larvae that would only emerge as adults later on. If there are only occasional wasps in the house, then traps with sweet, syrupy material would be a good attractant. There are several of those on the market.
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