Plan of Attack for JapBeetles - input needed

I’ve been a backyard grower of peach, tart cherries, berries for 20+ years…i moved to a new acreage two years ago and planted the same. So I have TWO growing seasons under my belt. This new lot has a huge infestation of Japanese Beetles.

Imagine walking into your orchard at the end of June and thinking, “OMG, this is what the Garden of Eden must have been like”…then by the middle of July the trees are over 1/2 defoliated and and have totally shut down growing for the year.

I’ve decided this is going to be my “go for broke” year and we’ll forego getting any fruit to get rid of these things. Its just not worth taking care of an orchard if this continues. This will be a “nuclear option”.

Situation: I live on the Mass/NH border. The beetles hit between July 1 and July 10 depending on weather. I’ve done some beetle products on the ground (grubex) and then once the beetles hit I did traps and went out 3-5 times per day to manually remove beetles (oh, please don’t tell me the traps are bringing them in.) When I dig around, I see the grubs in the ground. They are already here. My orchard is about 75’x75’ in a two acre field of grass.

Current plan:

  1. Around June 1, I will treat the whole two acres with Grubex. I’ll also try Milky Spore while I’m at it. I’m open to what you’ve found to kill the grubs. I’m open to try multiple approaches to kill the grubs.
  2. Once they hit, I’ll give my chickens a day or two to see how they do. Moving them to this area will be a real hassle.
  3. If they are still unchecked, I’ll be using Sevin or Bonide or other heavy duty killer to knock them out. BTW, Neem oil not only doesn’t work well but defoliates trees (thanks to those on this board who made me aware). I know this is not ideal, but i’m at the end of my rope. It is just not worth it to go through this again.

The blackberries and raspberries do fare better than the trees. It was almost a full time job keeping them alive last year. These beetles can cover a tree.

Any thoughts ?


I have had success with traps. I know about the research that says traps attract more beetles. I don’t place the traps until the beetles reach a level where I’m noticing a significant impact on tree foliage. Almost immediately there are significantly fewer on the trees and the traps fill quickly.


You want the traps outside the perimeter of the orchard, not within it. Use larger traps, like the kind made from trash cans, so you don’t have to empty them as often. But gorilla glue doesn’t work to make them. Nor duct tape. Get a vinyl pool tape or something similar. Do a search on this forum to find the instructions.

what type of traps did you use ? My traps were catching bugs, but there were still plenty of beetles on the trees.

I used traps two years ago and last year had almost no Japanese beetles. This year I got chickens and I’ve heard they love the beetles so if they’re bad this year at least I can trap them and they’ll become chicken feed

Eventually they will thin out but it may take years. Sparrows and other birds will eventually start eating them. It requires years of exposure to invasive species before the natives figure out how to exploit them.
Grubex works. Grubex is chitin eating bacteria. So they will attack grubs and even adults. You can also attract chitin eating bacteria by spreading around crab and lobster shells. Sold as fertilizer and contains lots of chitin. Feed them and they will come. So not only is it a fertilizer it attracts predatory bacteria.

I spread milky spores last year and am hopeful I’ll see less of those little devils from here forward!

Good luck.

I use traps and have trapped so many Japanese beetles that the population has decreased. Sure, traps draw beetles- therefore I don’t put traps in my orchard; but put them 100-200 feet out side of the orchard close to a tree line. I have 4 of the standard $10 traps which I hang on a tree limb about head high. Then check it every day. If full, I set a 5 gallon bucket, 1/2 full of soapy water near the trap. I then remove trap, cut a slit in bolttopm and dump all into the soapy water to drown. I then fold the blottom and place 4 clothspins to keep it closed.
I have used these traps four years, but I buy new lure each year on Amazon or a store; much cheaper.

I also have a trap that I fastened to the top of a five gallon bucket which I have 1/2 full of soapy water.

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I used a few of these traps. My orchard is slightly less than 1/2 an acre.

I would not combine Grubex with milky spore, as the milky spore needs a population of grubs to proliferate and spread through the soil, and if the Grubex is successful, you won’t have that. Also I wouldn’t let the chickens forage where you have spread Grubex. From what little reading I have done, Grubex persists for a long time in the soil and can have an adverse effect on non-target insects and on soil bacteria and fungi. Milky spore isn’t supposed to work in the colder parts of New England, but I used it in my yard in the Berkshire Hills of western Massachusetts when I had a bad infestation of Japanese beetles and it proved quite effective – years later now, I see an occasional Japanese
beetle, but nothing that troubles my fruit trees or garden.

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That’s good to know, I said it was ok but I thought it was a different product. You can buy grub eating bacteria it’s a BT strain, one product is called grub halt.
That’s what I meant to recommend. Works very well. Again one can add crab and lobster fertilizer to attract the local chitin eating bacteria. Either product is not cheap though.
You can also buy grub eating nematodes.