View Full Version : Japanese Beetles

07-17-2006, 09:09 PM
Anybody else having problems with these guys? They're terrible here! It's a real struggle to protect our beautiful roses and other shrubs. Here are some things we've tried that are somewhat successful:

Soapy water--mix up Dawn dishwashing liquid and water in a spray bottle. Spritz it directly on the beetles. It kills them pretty quickly (thanks to Joanne aka jdkiggins for this suggestion :) ) You can also use a sprayer attachment on the water hose to cover larger areas.
Japanese beetle traps--these can be used for quite awhile if you dump them every day. We must have captured thousands of the things in these traps! We have three set up at different points around the property. Don't put them too close to the plants you want to protect because the traps have an attractant in them to lure the beetles.
Hand pick the things--sometimes I take a small container of Dawn dishwashing liquid and water out to the garden and simply pick the beetles off the roses and other plants, and then drop them into the water. Kills them quickly.Does anybody else have other suggestions? This is the first time we've had to deal with these things and I would love to hear what has worked for you.

07-17-2006, 09:27 PM
Are these the little bugs that looks like lady bugs and are often mistaken for them?

07-17-2006, 09:39 PM
if they are same same as what are called Japanese corn beetles they are much bigger. This areas throngs with them but I don't have a garden so I don't have to wrestle with them. My photo of one: http://www.shutterstock.com/pic-440779.html

07-17-2006, 09:50 PM
I heard that the beetle traps actually attract all the Japanese beetles in your neighborhood to your yard.

There is something you can use to kill the Japanese beetle eggs. From what I understand, they deposit eggs in the soil at the end of summer and early fall. I haven't tried either method. But, I have an abnormally large amount of Japanese beetles on my plum tree this year.

Here's a link about managing them: http://www.pueblo.gsa.gov/cic_text/housing/japanese-beetle/jbeetle.html

It states "...be sure not to put traps near your garden or your favorite plants. Put traps at the borders of your property, away from plants the beetles may damage. Traps are most effective when many of them are spread over an entire community."

07-17-2006, 11:47 PM
That's it, Em! They're actually kind of pretty things, but oh, so destructive. Fern, they look a lot like miniature June bugs (to me, anyway).

Thanks for the link, oarsman. That's the best site I've found on them, and I've practically memorized it. Heh. Sad, huh?

You've had an abnormally large number on your plum tree this year? That goes along with what I've been hearing from others. This seems to be a bad year for them and they're devastating crops and flowers, etc. all over. :(

07-18-2006, 04:13 AM
We need to go into business together. We can make a million!

Here Japanese beetles are absolutely adored by children and adults. They keep them as pets. As soon as it gets hot out come the plastic cages which get filled with special beetle dirt and set with special sweet beetle jelly. Then either they are caught in the woods or more likely bought at some local store. They are sometimes even sold stacked next to food products and the like. And the prices they go for! Woa! The bigger the more expensive and I am talking upwards of several hundred dollars for the real fancy ones. :)

07-18-2006, 04:20 AM
If I could, I'd be happy to ship them to you! I bet I could round up a million of'em, especially if everybody here pitched in with their beetles. Oh, man, we could be rich, couldn't we? :roll:

Thanks for joining the conversation, madderblue! I'd forgotten that the beetles aren't pests, but are PETS, in Japan. :D

07-18-2006, 04:37 AM
the beetles sold in Japan are the large rhinoceros beetle and various members of the staghorn family. Those little bronze 'Japanese' beetles you are plagued with are not worth a yen!

We have something similar in NZ and I've always found soapy liquid works best although the traps sound great.

07-18-2006, 04:40 AM
I'll add my two cents worth - Japanese Beetles are very metallic looking - usually goldish with shades of iridescent green and/or pinkish. They very often have their hind two feet/legs up in the air. They love my Harry Lauderer's Walking Stick and they also love the loosestrife that grows wild. They are a real problem. We haven't found anything to use on them other than what's been mentioned.

The other bug that Fern mentioned is a foreign variety of ladybug (Chinese I think) that is pushing out the native ladybugs. These foreign guys don't have as many spots and are more yellow. They love soybean fields during the summer but as soon as the fields are harvested they flock to houses, etc. trying to get in and stay warm for the winter. These guys do bite. I'd love to know how to get rid of them too (but I did have fun one time running the shop vac on the outside of the house). Puma

07-18-2006, 08:45 AM
We keep them under control most of the time, but the last three or four years we've have swarms come in that overpowered everything. Hundreds of tousands, maybe millions of the little buggers. When this happens, you just have to wait them out.

07-18-2006, 09:51 AM
Yes, pdr! They are the rhinoceros beetles, and a few other of the 'big' variety (Hercules etc.). Darn! I thought it was such a good plan too.

I don't suppose anyone could manufacture a whole lot of those tiny 'horns' and glue them on the little fellas.

07-18-2006, 03:55 PM
Has anyone tried attacking the beetle larvae instead of the beetles? They feed on roots of grass from mid-July to October in my part of the U.S. I wonder if attacking the larvae in the ground this year will mean less beetles next year. (I can only hope)

Here's a recent article from one of our newpapers about beetle larvae:

07-18-2006, 09:41 PM
I wonder if the same treatment that works on roaches might work on them. Boric acid . . .or I got something called Roach Proof which was 97% boric acid I think, works wonders on roaches. They get the powder on their legs and take it back to their nest, which kills out the whole shebang. My inlaws had them once and someone had told me about the boric acid. When my mother in law went into the hospital I had to take care of her house for a while and I tried the stuff. The bugs never came back. Anyway, that was a long roundabout way of wondering if the beetles might take the powder back to their nest in the same way.

Of course, you'd have to consider what other kind of bugs, etc. might also get into it, plus I haven't a clue what it would do to your plant itself, but you could always just pick one here and there and hope enough bugs went back to the nest with powder on them.

07-19-2006, 10:59 AM
Do birds eat these beetles?

Import a few more Praying Mantis from other gardens?

07-19-2006, 11:47 AM
The other bug that Fern mentioned is a foreign variety of ladybug (Chinese I think) that is pushing out the native ladybugs. These foreign guys don't have as many spots and are more yellow. They love soybean fields during the summer but as soon as the fields are harvested they flock to houses, etc. trying to get in and stay warm for the winter. These guys do bite. I'd love to know how to get rid of them too (but I did have fun one time running the shop vac on the outside of the house). Puma

The best way I've found to keep them out is to find where they're getting in and seal those areas. In my case, a simple caulking of the windows has kept the majority of them out the last couple of years.

Beyond that, the vacuum has been the best way I found to deal with them once they were inside. A local farm supply store has also started selling a trap. I haven't tried it yet, but it uses a flourescent light, which I know they are attracted to, as bait.

07-19-2006, 01:54 PM
I use Borax mixed with sugar and water to kill ants when they get in the house. Just like the boric acid, the ants track the borax back to their nests and it destroys the nests. I would suspect that boric acid/borax would be harmful to most garden insects so I'd use it sparingly. Puma

07-19-2006, 03:07 PM
The very worst damage done by the beetles is to turf grass. The grubs eat the roots (I had to totally replant my front yards years ago) Inoculate the soil with milky spore bacteria and the grubs die, although not immediately. If the entire neighborhood treats, you will see very few beetles. I live in the country, so I treated my lawn with milky spore and put a few beetle traps up. (I love catching the ba$tard$) Don't see many any more.

07-19-2006, 09:52 PM
I wondered what the beetles natural enemy is in its natural habitat. Only thing I could find was this wasp (not agressive toward humans):


At the bottom of the page it gives info on how to get the wasps.

07-31-2006, 06:13 PM
Dang it I wrote a whole post and then erased it! Grrrr... ok well now you get the short version. Japanese beetles are a pain in the butt, milky spore will work but may require a few treatments- pheremones may attract larger numbers of beetles to your yard instead of trapping the ones you have- spiders will roll them out of their webs rather than eat them- beneficial wasps like plants such as dill, cilantro, fennel. Hmm what else did I say? My husband owns a pest control company and when dealing with ladybug invasions of homes it is usually a matter of sealing it up tight and using a vaccuum. (just like someone said before) Japanese beetles don't make nests like ant colonies so treatment isn't really the same (they won't take a bait back and share it another words)...Birds ignore them here- I can't remember what else I wrote :( But if you have any bug problems I can probaby find out an answer for you- my husband deals with structural pest control not ornamental- partially because when you engage in pesticide application for outdoor pests you enter into a vicious cycle - you cannot get rid of bugs outside- there are always more waiting to move in when you remove them. Pest insect populations (think prey) rebound far more quickly than beneficial insect populations (think predator) so you lock yourself into having to keep applying something to keep them in check. You probably all know that already but I just wanted to give you a perspective from someone who deals with pest control for a living. This coming from the organic gardener who's married to the pesticide guy? LOL :) (Yup - that is my short version LOL. )

07-31-2006, 06:34 PM
Wow, thanks, Laurel29! Welcome to the forum. We hope you'll visit us often. :)

My beetle news: ssshhhhh...they seem to have disappeared for now...hope they're gone for good...must try that milky spore stuff.