Japanese Beetle Trap Bags & Alternative Ways

We did have the milky spore treatment. We can tell a difference in the number of Japanese Beetles from last year, but have noticed that our big trees are still being injured by the pesky little beetles. Is there anything that we can do to help our big trees out?

 

It's good news that you've already seen a reduction in the number of beetles in your area. Some homes in the Regency community near us, have reported a 70% reduction in beetles for their homes since their early spring treatment date. I think we've seen a 30% reduction this summer in a few sections of Broadlands this first year. We hope to see a 50% or 75% reduction by next summer in those same areas as the spore continues to work underground.

St Gabriel Labs tells their customers that if the non-chemical method of knocking beetles into soapy water container method does not help you, while you are waiting for the spore to work underground, then as a last resort, they say try using a spray [edited to add: or use a systemic solution in lieu of a spray -- see next post for details] on the trees until the beetle population declines.

At the end of July through beginning of August, the adult beetle population declines very rapidly in our area, so it may not be necessary to use a chemical by that timeframe. Chemical sprays can be expensive (about $10 to $15/bottle), not to mention dangerous if inhaled by humans/pets/children. If using a chemical spray, remember to follow exact instructions on the label.

For the straight facts and unbiased answers to any question about pesticides, call the Oregon State University at 1-800-858-7378 or go to www.npic.orst.edu Their experts have access to the most current and largest knowledge database about pesticides in the nation.

Habitat team, under their philosophy, can not recommend using harsh chemicals at all. However, we'll talk with master gardeners and get back with you quickly on this thread with what else master gardeners recommend using to minimize damage on trees while milky spore is taking effect.

 

In answer to the question, how do I protect my trees while the milky spore is working underground? To reduce the number of chemicals that you use in your landscape and to protect your trees while milky spore is establishing itself underground over the next couple years, here is one master gardener's suggestion:


1. Keep your trees disease and stress free so they are naturally resistant to diseases & pests.

2. Autumn season: We don't recommend use of chemicals, however if you absolutely must or want to use a chemical to kill the adult Japanese beetles to protect your trees while milky spore is working underground, please do not use a chemical spray but instead prep your trees in advance during the autumn season by using a systemic-based insect prevention product (such as the latest version of the Bayer Advanced Tree & Shrub Insect Control Concentrate which contains imidacloprid). The protection lasts from 9 to 12 months. The systemic solution gets poured at the base of the tree and is absorbed by the root system into the leaves; the chemical protects the trees from within; the insecticide can not be washed off by rain; and the insecticide has less chance of getting into the water supply (when compared to other chemicals) than from a chemical spray. A chemical spray can wash off much too easily in the rain and get into local streams. With a systemic solution treatment, a beetle is killed as soon as it bites onto a leaf and the protection lasts 9 to 12 months (significantly longer than a spray). (Reference http://www.bayeradvanced.com/garden/products/details.cfm?id=12 ) Please don't use chemical sprays, if possible.

3. Spring Season: If you did not prep your trees in the autumn season with a systemic imidacloprid solution (perhaps such as the one mentioned above), you can still apply the systemic treatment in the spring (April or May). However, it just takes about a month or so (depending on how large your trees are) to maximize it's effect inside each tree. Remember the adult beetles will emerge mid- to late-June. Special Note: With an imidacloprid systemic such as Tree & Shrub Insect Control, if a few days later the tree shows signs of yellowing leaves, (which would be considered unusual in the Spring), then use plain ironite granules (non-fertilized) to quickly green up the tree leaves again. (Do not use the Ironite liquid because that contains fertilizer which might alter the pH of the tree soil.) Plain Ironite granules are best for counteracting the yellow leaves. www.ironite.com

4. Mid June through August:
Inspect your trees & plants early each morning.
Knock Japanese beetles into a container filled with very soapy water to kill them.
Beetles are less active in the cooler hours of the early morning and therefore easier to manipulate.
The sooner you wipe out the initial scout beetles which attract others with pheromone scent, the less beetles you will attract to your yard.
The habitat team does not recommend the use of bag traps as they tend to attract a good crowd of beetles immediately.

5. Recommend the milky spore powder treatment to your neighbors. It's the longest lasting product that can kill the Japanese beetle grubs. 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. See FAQs at www.milkyspore.com for more info.

 

The systemic insect prevention product is for protecting trees & shrubs only. Although it is still a strong and lethal chemical, at least it is more controllable than using a chemical spray. Chemical sprays can get into all kinds of places where you don't want them to be, like in one's clothes, skin, face, grass, streams, etc. The wind & rain can carry it to areas you wouldn't suspect, too, like onto one's deck, porch, patio or children's playset.

If one doesn't want to use any chemicals at all, then use a handheld vacuum to suck all the beetles off the tree. It halts the damage immediately. It's neat, tidy, no mess, no fuss, uses no chemicals, saves time, saves money. (Recommended by Fine Gardening Magazine, June or July 2005 issue.)

 

Re: Japanese Beetle Trap Bags & Alternative Ways

Resurrecting this thread.

We moved here last year and I recall seeing all sorts of info/promotion about the milky spore program but we were a little late to get in on the action. Have I missed it, or is there no longer the push to have everyone do it? Are master gardeners still recommending this course of action? (Is it too late in the season now to do it?)

 

Re: Japanese Beetle Trap Bags & Alternative Ways

You can buy the milky spore and apply it yourself. Takes about 15-20 minutes. I did my yard last year.

 

Re: Japanese Beetle Trap Bags & Alternative Ways

Does anyone know if milky spore dispensers still be checked out at the Nature Center? Has anyone seen milky spore powder being sold at Lowe's or Home Depot recently?

 

Re: Japanese Beetle Trap Bags & Alternative Ways

You may have to visit one of the garden centers, I know Merrifield had the stuff in the past.

 

Re: Japanese Beetle Trap Bags & Alternative Ways

I tried Bag a Beetle and it was a DISASTER even though I placed it upwind as suggested. It attracted 100% more than without the bag!

So I chose the milky spore solution two seasons ago as did my neighbor. I am amazed at the reduction in beetles, truly. If you haven't yet, get into the Milky Spore program fast! I highly reccommend it.

Sorry, didn't intend to sound like a commercial.