Japanese Beetle Trap Bags & Alternative Ways

Japanese Beetle Trap Bags & Alternative Ways

(printed in the July 2005 newsletter)

Summer [usually around June 15th] in Virginia is when adult Japanese beetles start to take flight to find tasty ornamentals for eating, per local landscapers. Virginia Master Gardeners and Habitat team do not recommend using Japanese beetle trap bags. The scent of the traps is so strong that it actually lures thousands more beetles toward the bag than the trap can actually hold, thus creating even more potential damage to trees/bushes/flowers in the surrounding area. [Several recent university research reports support this finding.*]

If you insist on using the traps, please be considerate of your neighbors and their properties and do not place traps within 50 feet of the lot line. Residents with small size proprerties are especially vulnerable as homes are very close together.

There are alternative ways to deal with the adult Japanese beetle. Master gardeners and Fine Gardening Magazine recommend the following:

• in the early morning flick the drowsy beetles with a long-handled spatula or spoon into a container of soapy water to drown;
  [*]suck them up using a small handheld "bug vacuum" (do an Internet search for those);
  [*]plant a ring of garlic and/or chives around affected plants as a repellent.
• And put down Milky Spore powder in your yard and flower beds.

One Milky spore powder treatment takes 1 to 3 years to be fully effective but can rid a yard of Japanese beetle grubs, thereby stopping the life cycle for 10 to 20 years. Only 1 application of milky spore powder is needed when compared to several applications of the milky spore granules (or other types of Japanese beetle grub control). For other interesting ways to repel or get rid of adult Japanese beetles, please see this thread and other chat threads under this Nature forum.


*please see below for excerpts from University research reports regarding beetle traps.

 

So, what do people think of japanese beetle bag traps? We’re curious to know.
Below are the latest extracts from research we could find online (so far). Please post your own opinions about the traps from your own experiences (good or bad). We'd like to know.

- Year 2004 report from the USDA Regional Integrated Pest Management Centers Information System:

"In recent years, commercial or homemade traps have become a popular means to reduce beetle numbers. Commercially available traps attract the beetles with two types of baits. One is based on pheromones produced naturally by female Japanese Beetles and is highly attractive to males. The other is a bait that mimics the smell of adult food sources and attracts both males and females. The baits can be so effective that the traps can draw in thousands of beetles in a day. However, only a portion of the beetles attracted to the area of the traps are caught in them. When this occurs, traps in a home landscape can actually increase Japanese Beetle problems rather than reduce them."

- University of Maryland's Coop Extension:
"The commercially available yellow Japanese beetle traps are baited with a feeding attractant and capture large numbers of adults. However, randomly spaced, single traps cannot provide effective control. Frequently, a single trap attracts beetles from the entire neighborhood and concentrates the damage in a small area close to the trap site. Research has demonstrated a 31-40% increase in adjacent plant damage when traps were used close to susceptible plant species."

- University of Purdue:
"Japanese beetle traps are effective at trapping many beetles, but unfortunately the net result is that more beetles end up in yards where traps have been set up, and more feeding damage results."

- Ohio State University:
"In most urban areas, traps tend to attract more beetles into the area than would normally be present. In this situation, adult feeding and resultant grub populations are not reduced."

- University of Kentucky Dept of Entomology:
"The spread of Japanese beetle infestation is primarily the result of flight by the adults. They can fly as far as 5 miles but 1 to 2 miles is more likely. Usually, they make only short flights as they move about to feed. Local infestations spread as beetles move to favored food and suitable sites for egg laying."

"The [scent of the traps] is such a powerful and effective attractant that traps can draw in thousand of beetles in a day. Only a portion of the beetles attracted to traps are caught in them. Small numbers of traps in a home landscape can actually increase Japanese beetle problems rather than reduce them."

"In most home landscape situations, using 1 or 2 traps probably will do more harm than good."

 

Alternative Creative Ways to Eliminate Japanese Beetles
(This is a open chat forum collection of ideas brought together by reading and research. Producers and writers on this web site are not responsible.) Please feel free to insert your own ideas.

Now that you've been "milky-spored to death" on a different thread ...... zzzzz (But seriously, we are continuing the milky spore program for those who have not yet signed up.)

Meanwhile, thought we could open up a new thread on alternative somewhat natural organic remedies to eliminate and repel adult Japanese beetles (those not at the grub stage) to try to prevent our flowers and trees from being destroyed this summer. This discussion may help our community deal with the Japanese beetles in a 1-2 punch (at the grub stage and at the adult stage) while the milky spore is working underground to establish itself.


We will see some Japanese beetles emerge around June 15th in our area (according to a very experienced organic lawn care company). So, it is good to be prepared. We are posting a few remedies that have worked for some gardeners, here. Please feel free to post the remedies that have worked for you.

 

Bettle traps make great gifts to give to your neighbors.

 

Here's a list of alternative natural organic methods which can offer you a two-prong approach to eliminate Japanese beetle in the adult stage or in the grub stage. These ideas come from various sources, not in any particular order:

To eliminate Adult Japanese Beetles:

• The Basics:Keep plants healthy. Stressed plants are more susceptible to pests.
• Vacuum Your Trees Now & Then: This technique is recommended by Fine Gardening Magazine and some old-timer master gardeners, believe it or not. Use a handheld vacuum to suck up the beetles from ornamental trees/shrubs. It's quick, neat & tidy with no chemicals involved. No mess, no fuss. Halts the bug damage immediately. Here's a link for one rechargeable bug vacuum: http://www.smarthome.com/6118.HTML . There might be others on the market.
• Soapy Water Remedies:
  • Soapy Method #1: Knock the slow-moving beetles (with a long-handled spatula or spoon) into a container of very soapy water to drown them quickly during early mornings. Use several drops of dishwashing liquid and water. The soap film kills the beetles, as opposed to the actual water. This technique especially works well in the beginning stages of a beetle infestation (usually June 15th in northern VA). When you see the first beetles arrive, use this technique to minimize damage to your ornamentals and leaves. Scientists and entomologists have found that the earlier in the season the beetles are eliminated, the less damage one will have on the flowers/trees overall, because you will be getting rid of the "scout beetles". It cuts down on the population attractant, since beetles are social and will congregate together or wherever the female beetle goes (the female does the scouting for suitable egg-laying sites). This remedy also works to halt immediate damage.
  • Soapy method #2: If you already has several masses of beetles, here's a similar, technique which may work for you. Prep in advance by collecting the following items: a lightweight soft broom, a large plastic tarp, a large spray bottle filled with thick soapy water, a water hose, and a large empty bucket. Spray a thick heavy soap film all over the tarp. Around 6 or 7 a.m., place the tarp under your infested tree or bush and then gently brush the leaves (with the broom) knock the drowsy beetles down onto the tarp where they will temporarily stick. Spray the stuck beetles immediately with the soap spray water bottle. Then use the hose to rinse the beetles off the tarp into the large bucket. After a few minutes, carefully dispose of the bucket of soapy water.
  • The soapy water remedies work best in very early mornings around 6 or 7:30 a.m. The natural defense mechanism of most insects if disturbed while sleeping is to play dead, roll and drop wherever gravity will take them. Don’t try the soapy water routine in the afternoon when beetles are awake otherwise they’ll just fly away.
• Repellent Teas: Make teas from branches of plants that Japanese beetles naturally avoid. Per the University of Maine coop extension, the beetles typically avoid: forsythia, honeysuckle, and privet. Or lay out boughs/branches of these around susceptible flowers/trees/bushes.
• Repellent Plants:
  • Plant Japanese beetle repellent plants near other plants susceptible to beetle feeding, which include: chrysanthemum, white geranium, garlic, rue, evergreens.
  • Per Univ of Ohio the adult beetles do not like to feed on ageratum, arborvitae, ash, baby's breath, garden balsam, begonia, bleeding heart, boxwood, buttercups, caladium, carnations, Chinese lantern plant, cockscomb, columbine, coral bells, coralberry, coreopsis, cornflower, daisies, dogwood (flowering), dusty-miller, euonymus, false cypresses, firs, forget-me-not, forsythia, foxglove, hemlock, hollies, hydrangeas, junipers, kale (ornamental), lilacs, daylilies, magnolias, maple (red or silver only), mulberry, nasturtium, oaks (red and white only), pines, poppies, snapdragon, snowberry, speedwell, sweet pea, sweet-William, tulip tree, violets and pansy, or yews (taxus), wave petunias. Add to or delete from this list based upon your own experiences.
• Netting Cover: Cover plants with a floating row cover. This can offer complete protection against flying adult beetles, however, make sure the netting does not trap the beetles, that emerge from the soil below the plant, inside the covering.
• Chrysanthemum-derivatives Shampoo: According to one local organic lawn care provider, a spray made from fatty acid soap/shampoo and chrysanthemums will instantly kill the adult beetles. Although this is an organic remedy, be selective and use precision and great care with chrysanthemum-derivative ingredients as this might also accidentally kill beneficial insects, too. Look for the spray on the internet. Note that the effect of chrysanthemum derivatives on humans is still being studied.
• Natural Predators:
  • Attract native species of parasitic wasps and flies. Experimental parasitic wasps can be used to attack the adult beetles. Look for these at local garden nurseries. Use with care.
  • Some medium-sized to large birds will eat the beetles.
• Natural Repellent Sprays:
  • Garlic spray on plants/trees can repel the beetles. The garlic scent dissipates within a few minutes, however the bugs will still detect it's smell. (This method is used by large commercial hotel chains to repel all kinds of insects from indoor/outdoor potted plants.)
  • Spray plants attacked by beetles with neem oil. This might help to repel beetles.
  • Spray selected plants with Garden Safe organic botanical insecticidal soap.

To eliminate the Japanese Beetle Grubs:

• Recommend the milky spore powder treatment to your neighbors. Several yards inoculated with Milky Spore create a beetle free zone in a very short period of time. Remember, beetle grubs attack the roots of your grass, plants, shrubs and trees causing as much damage underground as they do above. Milky spore powder need only be applied once. After established, it will halt the life cycle at the grub stage for 10 to 20 years. Use on a street-wide or community-wide basis. Apply the powder to flower beds, grass, and sunlit tree save areas, anytime the ground is not frozen, and water the powder into the ground immediately. The powder spore will establish itself faster in the ground if it is applied in July or very early August (because August/September is when the grubs begin to feed most heavily and you want the grubs to eat the spore hidden in the ground).
• Maintain a high level pH in your lawn, as this discourages the grubs from feeding on the grass roots, per local and national lawn care experts.
• Plant high quality tall fescue grass type in the lawn, which is hardier than other types of grass to discourage the grubs from feeding on the roots. Tall fescue is also more disease resistant, too. This is a good cool weather grass which survives well in northern VA. (Recommended by local organic lawn care companies.)
• Try using insect-eating parasitic nematodes (Steinernema glaseri and Heterohabditis bacteriophora and Heterohabditis heliothidis, tested 90 percent effective while in the experimental stage) to control Japanese beetle grubs in turf grass. Begin application of this agent in mid-May. Nematodes need some care to stay alive in the ground (some chemical pesticides might kill them). Nematodes are currently recommended as an experimental technique at universities, per organic gardening books. Do a key word search on the internet to find more info, and/or please check with your local nursery.

All those above remedies and possibly other natural remedies, will help you get through the month of June and July when the beetles feed on the plants until the milky spore kicks in and decreases the population.


Please add to this thread & let us know of other remedies that may work.

 

Well I have tried everything I can think of and these stupid things destroy my plants. I have showered my trees with insect killer, I have put down the grub killing fertilizers. I have done this now for 2 seasons and over the weekend the beetles came out in force. There were so many that all of my trees were just covered with them. The only thing I have found to keep the damage to my trees and plants to a minimum has been these beetle bags combined with the beetle killing sprays on all the trees and plants. I don't know why it's so bad but if I don't do this my trees are litterally covered with beetles.

I'm am going to have the milky spore put down but that won't be helping me this year.

 

Well, here's a yukky remedy that I found in an organic insect book. Use with extreme caution.

• Make a dead bug flavored juice spray from an old gardeners recipe which apparently lasts for 2 months to repel beetles. Beetles are repelled by the smell of dead Japanese beetles. Please use an old blender - not your family's food blender! Recipe is: lots of dead beetles, water, garlic. Please use care with this remedy, since there can be a risk of disease or damage spreading to plants.


If Japanese beetles are repelled by the smell of other dead beetles, I wonder if that could be another contributing factor in why Japanese beetle bag traps can fail? If the bags are not changed daily, then the smell of dead beetles will have a secondary effect of repelling beetles from the bag after they get close enough to find the first attractant. Maybe, after traveling from miles and miles away to find the bag, the beetles do a u-turn at that point and settle on nearby trees/plants as their consolation prize.

The beetles are typically very lazy. They probably would not have come all that way in the first place, if the scent of the bags hadn't been so strong in attracting them. Just think, one could be attracting lazy beetles from as far away as Sterling when the beetles probably would have just stayed there otherwise? (No offense to Sterling. We have enough of the same problem, though.)

The beetle bag manufacturer instructions do state that the bags should be changed regularly because the odor of dead beetles will repel new arriving beetles. (I hear that the odor of dead beetles is so bad that it repels humans, too!)

 

These days I can change the bag every other day. I put a bag out last night and this morning it was half full. In this heat you do not want to let it sit for to long otherwise the smell is horrible.

 

I am going to do the soapy bucket method tomorrow morning. Fortunately there have been some grackles feasting on the emerging beetles in the lawn - I saw one bird cram about three in his mouth at once. Some have been dining on the ones on my crepe myrtle as well - keep it up guys.

jaeris

 

LostSoul, that's true. Don't let the bags sit out if they smell badly. If one insists on using the beetle trap bags, the bags should be changed at a minimum every day. If the bags contain dead beetles that start to smell bad (usually within a day or two), the living beetles will make a u-turn away from the bag and they will land on your closest ornamentals, instead, as the consolation prize.

If anyone notices a neighbor mis-using a beetle bag, please try and point that neighbor to read this chat thread or try to gently respectfully educate them. If they still insist on mis-using the beetle trap bags -- against Virginia Master Gardener recommendation -- then attempt to get (or help out) your neighbor to change the bag daily, so that the bag doesn't fail as badly as it typically does.

The trap bags fail because most consumers don't understand all the instructions and nuances of problems associated with the bags.

As afgm pointed out earlier, it's an old gardener's joke to give a beetle trap bag to a neighbor - so that all the beetles will fly over to that person's place instead. Unfortunately for us, the joke backfires when the lots are small and close together as they are in several sections of Broadlands. Your neighbor ends up attracting beetles to both of your small yards. It also double backfires when neighbors don't change bother to change the bags daily because beetles give up on the bag when it is stinky smelly and they fly back to your yard instead.

Japanese beetles. sigh....

 

Just got off the phone with Spectracide who makes one brand of japanese beetle bag trap. They said they are in the process of updating their instructions in bold letters on their product to inform customers to change the bags daily.

Again, for those not in the know, Virginia master gardeners and Broadlands Habitat team volunteers currently do not recommend the option of using japanese beetle trap bags. Reasons: (1) the scent lure of the trap is too strong in that it attracts many thousands more beetles to the customer's local area than the bag can actually capture -- thereby causing more-than-usual beetle damage to the customer's ornamentals; and (2) the instructions for the bags may not be specific enough, are frequently misinterpreted, mis-read, too complex for customers to understand, in turn causing customers to mis-use the bags unknowingly, thereby making the customer's beetle infestation problem a hundred times worse than it would have been.

Instead, Virginia master gardeners do recommend many other different remedies to eliminate adult japanese beetles (both organic and some chemical).

 

I am in a section of houses that was built last year. I haven't seen too many beetles around, but one of the new maples near me in the common area seems to have been attacked by something. I'm guessing Japanese Beetles. What time of day should I look for the munchers?

Pam D.

 

What if you asked your neighbor to move it (we have had milky spore put down in our yard) and both neighbors on each side had the bug bags. One neighbor removed their bags entirely - we were very greatful and the other just moved in from their side yard to the back yard but it's about 2 feet from our property line - near our trees in our backyard.

What kinds of problems will we have because of this? I find the bags smell after a time. Plus they attract so many of the beetles that when I am in my backyard near the bags, I get attacked (not meant harsh here) with beetles flying in my hair. YUCK!

 

If those are Japanese beetles, then the little munchers are active during the hottest part of the day, and typically show up from June 15th through end of July (and sometimes into early August) in northern VA.

But first things first, identify the muncher before seeking a remedy to treat it. To see some clear photos of Japanese beetles, type " japanese beetle " in the search bar of google.com, then click on Images above the google search bar, then click Search Images. Or, simply go to: http://images.google.com/images?q=japanese+beetle&hl=en&btnG=Search+Images . (This is also a great way to see different images of anything, really. I regularly use this method for gardening and finding images of colorful flower species. It saves time.)

If this is not the beetle you see on your maple tree, then you have a different beetle infestation.

For a list of trees/plants that the Japanese beetle typically attacks (and ones they avoid), go to the following site. There are also some good life cycle facts about the beetle on this site, although the reference to milky spore is a little out of date:

http://www.uky.edu/Agriculture/Entomology/entfacts/trees/ef409.htm

[The reference to Milky spore doesn't get the most flattering description, but that is because this article includes older references to Doom & Japidemic products which no longer exist on the market today. Doom & Japidemic failed and were taken off the market because their lab formula was not correct. Milky spore is still the original product using the original Professor Dutky formula, and it works as intended (albeit very slowly, but nonetheless naturally and safely), per several independent university research reports.]

Do you know which type of maple tree you have? Is it the Norway Maple, or Japanese Maple, or Red Maple or Sugar Maple or Silver Maple? According to this article, Red Maple and Silver Maple are relatively free of adult Japanese beetle feeding. On the other hand, Japanese and Norway Maples are nearly always attacked by Japanese beetles.

 

If my ID are correct, the beetles are rather fond of the sugar maples, but have avoided the red maples. The oak tree has also made a relatively good snack.

I haven't really seen the beetles, so maybe they have moved on, but I will check midday if I get a chance.

Edited to ask another question - other than the unsightliness of the damage, should I would about the health of these trees? They were just planted this spring.



Pam D.

 

Regarding permanent damage to trees:
[edited to add the following sentence] After 3 or 4 years of continued defoliation by japanese beetles, the continual damage could hurt the growth of the tree. One will notice that leaves no longer grow in certain areas of the tree, creating a bald tree branch effect. Japanese beetle damage on street trees can be unsightly. The defoliation of the leaves gives the appearance that the tree is dead (whether it is or not). Noticeably dead-looking trees are not exactly an asset when selling a home during the summer months. It can be expensive to replace dead trees and potential buyers may not be sure of the potential recovery in a dead-looking tree. Alternatively if not selling the home, one might want the trees to look beautiful for an outdoor family photo, a barbecue with friends, and/or to keep the neighborhood looking good to retain general home values.

Regarding health and care of maple and oak trees:
Be sure to water young/newly transplanted maple or oak trees during dry periods while they become established. Transplants do not yet have an extensive root system to reach deep into the soil and take in water, so they can become stressed easily. This also makes them more susceptible to injury from insects and diseases. The first year, unless there's a soaking rain, in spring and fall slowly pour two to three bucketsful of water around the roots every two weeks; in summer every week or ten days. Maintain the 3" of mulch around the base in a wide saucer shape to help collect and retain rain water. On the other hand, do not over water.

Here's an interesting article on the disease and insects of maple trees: http://www.maple-tree.com/maple-tree-insects-and-disease.html

The following is a helpful article on caring for transplanted trees & shrubs, in general, from the VA coop extension office: http://www.ext.vt.edu/departments/envirohort/articles/woody_ornamentals/transtas.html

Related articles from the same index are at: http://www.ext.vt.edu/cgi-bin/WebObjects/Docs.woa/wa/getcat?cat=ir-ln-tsg-tr .

 

Two questions...

When does Japanese beetle disappear? (late Aug / late September )

Do the rain / T storms help or hurt Japanese beetles when it comes to their survival?

Thank you.

 

Japanese beetles disappear around mid-August after they lay their last eggs in the soil, although some may be found until the first frost. [Edited to add:] The worst of the defoliation damage from feeding adult beetles occurs from June 15th to end of July in our nothern Virginia area.

Although you might still see a few beetles flying around in early August/September, there is usually not as much more damage on the leaves. But, watch out, because in early August, a new type of damage occurs when the eggs hatch underground and grow into grubs which begin to feed heavily on the grass roots. (It's why milky spore powder was recommended to be applied to the soil before or during early August.)

Rain and thunderstorms don't have any negative affect on the adult Japanese beetle or the grub. The adult beetle is tough enough to withstand being heavily rained upon. Although the adult beetles can die in a container of very</u> soapy water, it's the heavy soap film that kills them, not the water. Meanwhile, the grubs underground prefer moist or wet soil as opposed to very dry soil. Heavy rain doesn't hinder the Japanese beetle (adult or grub stage) at all.

Another good information article: http://ohioline.osu.edu/hyg-fact/2000/2001.html

[Again, not particularly flattering about milky spore, but the article was written in 2001 before Japidemic and Doom (which were the wrong lab formula, as mentioned in a previous post in this thread) were pulled off the market.]


Although Habitat team can only promote organic methods of controlling Japanese beetles, there are also some chemical methods mentioned in this article which some master gardeners promote and use.

To balance this out, remember that any chemical strong enough to kill a Japanese beetle will be very harsh, and that there are usually severe consequences to using the chemical product and having the environment/your skin/your lungs/your pets/etc. exposed to the chemical. So, if you insist on using chemicals, do so with caution and extreme care. Recent chemical pesticides were pulled from the market by the EPA because the chemicals caused nerve damage problems in pets and humans.

Whichever methods you use to control Japanese beetles, please select very carefully.

 

Well... One of your neighbors is knowledgeable and considerate; while the other one does not understand the problems associated with the beetle bags (and is probably "junior-level" or new to gardening). (Or, maybe could be inconsiderate? Not sure.) Advanced gardeners don't use beetle bags, because they understand the entire picture and intensity of problems that are created with the bags.

It's a perfect example of what we were talking about in the July 2005 newsletter article about beetle traps. Once again, if one insists on using the traps, please be considerate of your neighbors and their properties and do not place the beetle traps within 50 ft of their lot line. Otherwise you will upset or aggravate your neighbor, for certain. Residents with small size properties are especially vulnerable as homes are very close together. As mentioned previously, Virginia master gardeners do not currently recommend using Japanese beetle traps. Instead, they can recommend many other alternative ways to control the Japanese beetle (both organic and chemical).

Problems frequently reported with beetle traps are:

• if not changed daily, the beetle trap bags will create a huge stench (originating from the dead beetles rotting inside the bag). If one has never smelled a bag of dead beetles before, trust us, it’s an experience one will not easily forget.
• If the bags are not changed daily, the trap begins to lose effectiveness, because live beetles will sense the smell of dead beetles and will begin to be repelled away from the bag, thereby negating your effort to capture all the beetles. Instead, the beetles will begin to land on nearby trees/plants and defoliate those if they can.
• the pellet with the floral/mating scent lure of the trap is typically made from female beetle mating hormones and food scent to attract both males and females to the bag. The manufacturers currently make the lure scent too strong such that it attracts many thousands of beetles from up to 1 or 2 miles away (and in some rare cases as far away as 5 miles). Even with the best scenario where a bag is changed daily, thousands more beetles will be attracted by the lure scent to your yard -- and to your neighbors’ yards -- than would normally have found their way under a no-bag situation. It’s likened to hanging out a neon fast food restaurant sign that says “free food today” and the beetles fly in from everywhere lining up just to get a whiff. Because the scent lure is too strong, the cure is worse than the original problem.
• if the bag is located within 50 ft of your neighbor's lot line and you both have small-sized lots, it can become impossible for your neighbor to enjoy his/her own backyard during the months of June/July/August because of the stench of an old trap bag and/or because of all the beetles that the bag naturally attracts.
• interestingly, the stench of rotting beetles inside the bag also attract nocturnal creatures such as skunks, feral cats and other curious creatures. Curious nocturnal creatures have been known to tear open the beetle bags and spread the contents everywhere.

Again, VA master gardeners do not currently recommend using beetle trap bags to control the Japanese beetle. There are other better methods to deal with the infestation.

 

Our neighors are really nice so I just think they just don't know. So far they have been pretty good about the emptying of the bag. I also noticed that our tree and plants on that side have not been realloy effected yet.