Oh Nooooooo! I’ve never heard of that! Here they come. They eat and destroy. And they leave and don’t show back up till the next summer! That is awful. Like ‘Groundhog Day’.
I have noticed a bit of a second surge this year myself. I wouldn’t say they ever completely left but it seemed to die down and then I got hit bad again this past week. The beetles almost look smaller too…late hatchings? I didn’t think their life cycle accommodated a second generation in one summer.
@jcguarneri my youngest trees also got hit extremely hard by those brown Asiatic beetles. It took me a few weeks to figure out who was doing all the damage as they only come out at night. I also learned that they hide at the base of the tree of interest under mulch/dirt during the day. I’m in Mass FYI.
Thats how it still is for me. Yeah this was a few rounds in the evening after work. They are awful!
So i went ahead and did an application of 50 million beneficial nematodes(SF,HB,SC) since the HB are most effective against the JB’s however there was more PC and SWD at my place with everyone elses fruit getting wiped out. Those are a little cheaper and provide decent population control the next season but things are stupid hard right now and we need to focus on whats essential. Picking them feels a lot better than letting em just destroy everything so i made a sous vide et betelgeuse
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Hi. I have made a little table of the control approaches that I have read on this thread and another 2015 thread on Japanese Beetles in apple trees. For my part the primarily affect strawberries and hazelnuts. These would be exfoliated without my yearly manual interventions. The peaches, apples & blueberries are less affected.
Carbaryl (Sevin)
very effective
Observed by Appleseed70 (Japanese beetles in apple trees) + others
Pyrethroids (e.g. Olpea, Alan, triazicide, acetamiprid…)
effective
observed by Appleseed70 (Japanese beetles in apple trees) + others
Neem Oil
somewhat effective
various reports
Milky Spore
unknown effectiveness, may depend on local environment
Various
Beneficial nemetodes
unknown effectiveness, may depend on local environment
Levers 101, me
Beetle Trap (presumably pheromones) Includes various schemes to modify commercial traps to hold more beetles
Effective, it traps them well but attract more beetles to your area
various reports
Diatomaceous earth
unknown effectiveness
brought up by PomGranny
BeetleGONE (Bacillus thuringiensis)
unknown effectiveness
brought up by Kurt (of Phyllum Bioproducts. I believe they are associated with BeetleGONE)
Spinosad (product of soil bacteria)
uncertain effectiveness
observed by Susu, Nfg831_Z6b
Pyganic (pyrethrins)
uncertain effectiveness
observed by Fusion Power, seemed to work in that case
I am sorry for any I may have missed.
Oh yes, here is the most common method:
Hand picking (with or without assistance of a hungry chicken, or wet/dry vac)
effectively kills Japanese beetles, but even if therapeutic can be very time consuming.
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My first success at learned animal behavior trying to teach predators what an amazing source of protein the japanese beetles are.
I have been trying to take the ones i kill with my hands and set them on a post for birds or wasps and this was not working as they are already dead and thats not how these guys eat. The birds my cat keeps away pretty good so i am lost there, however i got wasps. I have been crushing them so the brains leak out but they are still alive and giving them to wasps (Wasps are asshole’s also!) and this is a picture of my success. I hope this spreads 
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That’s the most hardcore story I’ve heard in a while. 
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Thanks i was trying to hold them up to the wasp nest and this was just making them upset so then i tried with comfrey leaves also to no avail and so i followed them a few feet over to my garden and drop them near them and that one gave me the “Alright dude i can feel what you are putting down here” but still drug it into the basil leaves a bit deeper to gorge himself. I don’t know if they are doing this on their own yet but i have gotten multiples to do it so i am feeling pretty successful.
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I like that idea of bringing a bowl of soapy water to catch the beetles from below, as they like to dive quickly towards the ground when you threaten with a hand from above. Soapy water usually ensnares (and suffocates outright) flying insects. I’ll try that next time.
It’s mid-June 2021 and I notice these beetles are solely going after plum/pluots leaves in my orchard. Cherry, peach, apple, pear, apricot, jujube, persimmon leaves are seemingly unfazed.
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I really like those wide mouth protein containers for collecting them. Sometimes when using a bowl I would spill it on myself and that was frustrating. This way they never get out and even when you keep em clean and rinse it out they just have a smell and it’s nice to not get it on you or the plants and be able to get up in there and knock em off.
For me they first swarm young seedless grapes and then green beans then plums then sometimes they get to my apples.
I have some pole and soy beans growing but not (yet?) bothered by the beetles.
It’s amazing you can catch so many! Much of the time, the beetles just fly away or drive into the grass and I can’t find them. That’s why I thought a catch basin with water and soap would be helpful to catch them while they dive.
Anyhow, I noticed the preoccupied beetles that are on top of each other 
, are the easiest to catch.
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. Yeah man they are.
You just kind of approach em fast and put the jar under and brush all down the leaves. Grapes are the hardest for me and I just have these wee lil seedless grapevines for my wife that have never really made it into full size since I started them the same year the jbs hit my place. I’m hoping we have experienced peak jbs and some control is starting to happen.
If the beetles fly off before you can drop them into your soap water pan take a small spray bottle of dawn/water. Shoot a stream onto the beetle and they will stop flying and then you can slide them into your soap water container.
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A bucket would seem to be the tool for this
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I have seen a few jbs showing up…the masses haven’t hit yet. We have a couple plums of some type, I think they’re just red ornamental…but they get devastated if I don’t spray with something, and even then, I don’t get much control. Can I spray the tree with a dawn/water solution and control, or do the jbs have to be submerged?
I’ve not tested whether dawn+water spray kills these beetles, but I know this combo will suffocate yellow jackets.
According to this link, the japanese beetles are suffocated by soapy water.
I’ll have to try myself.
Direct coating most any bug with soap will suffocate it
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A bucket is too heavy (for me). I use a wide mouth ‘pickle jar’.
I like @Auburn idea - the spray bottle. Gonna try that one.
I did want to say that our Japanese beetle population seems to have decreased 100-fold. We hand collected them last year (Bop-the-Beetle) - and were hoping that we’d get to them before they had ‘families’ . . . and we think it must have worked! We only find about 20 or less - each evening. Whereas, last year - it was many many more.
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I’ve used the spray bottle, too.
I only put a few inches of water into the bucket. The wide opening keeps them from dropping away to escape
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I picked cherries today, and whilst sorting out the bad ones I found one (1) tiny stunted little JB. It lookslike the drought this spring wasn’t healthy for them. Good.
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