Japanese Beetles

[Sergeant Slabber]

I've been wondering why so many of my plants and trees have holes all over their leaves. Yesterday I saw a few bugs on some leaves and after doing some research found out they are Japanese Beetles. They are really doing a number. As far as I can see up in our trees the leaves have been eaten. I read that they can eventually kill the plant. I would say that I have about a dozen trees affected at this moment. Has anybody dealt with these suckers and can give me some ideas on how to treat for them? I know there are some sprays out there, but I don't know if you have to treat the entire tree for them to leave. I mostly have mature trees that are 50+ feet tall. Any help would be great. Thanks!!

[fishin ike]

I could be wrong on this, but to my knowledge they were imported to eat aphids off of our corn and soybean crops.I have seen them eating bug roadkill off my truck, so I don't think they would be harmful to any plants or trees.

[Powerstroke]

The insects that sgt is talking about do definately eat plant and tree foliage. Since we are now in the adult stage you need to apply a foliar insecticide spray. You do need to apply to the whole tree if you really want to protect the tree from further damage.

You can get Orthene or Sevin at a garden store, but for tall trees you may need to hire someone.

The most effective way is to kill the grubs. They are easier to target and can be done by anyone. You apply an insecticide to the lawn in early June and this will kill the grubs. They don't mature and don't become leaf munching beetles.

New eggs will hatch in the next month or so. You can still apply for the grubs right now to get the first growth stage. You won't get rid of any adults this way, but you will help save your plants for next year.

Something you can do that doesn't require chemicals is to vigorously shake small trees and shrubs early in the morning when beetles are sluggish. Place a plastic sheet on the ground so that fallen beetles can be captured and destroyed.

[Sergeant Slabber]

Thanks for the info Powerstroke! I think I'll probably have to hire someone since the trees are so tall and I would like to treat the whole thing. I will treat the lawn again. I did put an insecticide on the lawn in early June but apparently it didn't do the job very well.

[Powerstroke]

When trying to treat for the grubs, make sure you have a product designed for the grubs and the rate is appropriate. Grubs are harder to kill and the product has to be watered in very well in order to get the chemical down into the soil zones where the grubs feed.

A general "lawn insecticide" isn't usually strong enough for large grubs. Its great for sod webworm, ants and other lawn insects, but for the grubs it usually needs a heavier dose if its okay for grubs or you need a different product.

[Sergeant Slabber]

When I did the lawn in June it was in dry conditions and I'm sure that's what happened, it didn't get down in the soil deep enough to really impact those grubs. I went and bought some Sevin this morning which looks like it really targets Japanese Beetles. Do you have any recommendations for a company that would spray for these on my large trees? You can email me at [email protected] Thanks!