<p>Over the past few years I have had skirmishes with Japanese beetles over my rose bushes. They show up halfway through the summer, I periodically go around and brush as many as I can into a bucket of soapy water. Repeat on both side periodically. But today I noticed that they are in my elm trees. LOTS of them, turning the leaves into little skelton frameworks of a leaf. This is war… the roses are just an annoyance, but the only two shade trees I have in my yard of any size are these elms. Anyone had any luck getting rid of these pests?</p>
<p>Buy a Japanese beetle trap. It works really good. I can’t tell you how many million beetles I have caught with one but I notice every year I have fewer and fewer beetles. </p>
<p>The trap is a plastic piece you hang and you stick a scented bait on it and the beetles fall into a black plastic disposable bag hooked underneath and can’t get out. They sell them in home improvement stores.</p>
<p>I think this year they are particularly bad; they are decimating my raspberries and roses, as well, and I don’t remember last year being so nasty. I’ve gotten to the point that I can squish them barehanded. I hate the way they can’t be happy with just eating the leaves, but destroy the blooms too.</p>
<p>As far as your trees are concerned, what I’ve heard is that a tree can be practically defoliated and still survive–as long as it doesn’t happen several years in a row.
I don’t know of any quick, non-toxic controls for them, and it’s hard to see how you could apply them to a tree, anyway. On roses you can spray Neem oil, with care because it is also poisonous to other bugs; I don’t use it because I’m too lazy, and I have too many roses. I’m planning (as soon as the heat breaks) to apply milky spore to my lawn; I haven’t used it at my current house, but I’ve used it for years in Massachusetts, to break the cycle of larvae (it’s not a magic bullet, but it does help).</p>
<p>Don’t you just hate them? As you may already know, once the little buggers are adults they are almost impossible to kill other than by physically removing them from the plant. You should continue to brush them off as you’ve been doing so that they don’t cause significant damage. I have found the traps sold at home centers to actually attract beetles from the surrounding environs, so I don’t like them. I usually brush them into a container of water and let them DROWN. </p>
<p>Soon, the beetles will burrow into your grass and lay their eggs, which will hatch in the spring. So, be sure to treat your yard at the appropriate time with a beetle grub control agent. This should significantly reduce next year’s population.</p>
<p>[Control</a> of Japanese Beetle Adults and Grubs in Home Lawns](<a href=“Site | Ohioline”>Site | Ohioline)</p>
<p>Spraying or dusting with Sevin will kill the adult beetles. On the elms, Bayer makes a systemic insecticide that you mix with water and pour around the root base. I’m in zone 5 and usually apply it during May-June. I use it only on the buckeye trees (bettles don’t seem to affect my maples and tulips) and it does a wonderful job. The buckeyes used to get skeletonized every year and now the beetles don’t touch them.</p>
<p>shyanne in post #2 has it right. You might need more traps than you think but they do work and they drastically cut down on both this years damage and next years population. The traps fill up fast.</p>
<p>Gourmetmom, can’t brush them out of the top of the elm trees, they are maybe 30 feet tall. That is why I have to change tactics. I looked into killing the grubs a few years ago, but that stuff is so toxic… I have well water, and the rose bushes and one elm are right above my well cap. So I am reluctant to apply anything really nasty, especially in that area.</p>
<p>I just got back from stopping at two hardware stores, and both are out of traps. 
Apparently it is a big year for the little critters in our area. One of them said they will have traps tomorrow morning, and they open at 7, so I plan to be there.</p>
<p>I think our stinkbugs have killed off the Japanese beetles. You wanna come out to our place and collect stinkbugs?</p>
<p>Don’t want the stinkbugs, but I have noticed the bees tussling with the beetles when they are going after the same flower. The bee will cover and sort of wrap around the beetle, buzzing like crazy. Stinging them, I hope! Just need more bees…</p>
<p>I hate Japanese beetles…they’re in my roses and crepe myrtles.</p>
<p>I wonder if the Bayer flower/rose care that kills them systemically for flowers/roses will work with trees???</p>
<p>Bayer makes the systemic insecticide for roses and also the one for trees. Both are sold at Wal-mart, so it would be easy to compare labels. The rose one is (I think) a 3-way product, also having fertilizer and fungicide. That might be the only difference. The tree product may also be stronger, since it seems like a tree would require more product.</p>
<p>I hear ducks eat beetles-
we don’t have any- but I would try nematodes & diatomaceous earth .</p>
<p>Nematodes really works. Ihad the same problem, beetles on roses, grubs on the lawn. I treated the lawn with nematodes two years ago and haven’t seen beetles on my roses since.</p>
<p>The first year I put the traps out I was changing the bags every week and this year I think I caught maybe 30 beetles in all. I live in a really woody area.</p>
<p>We’ve had good luck treating our lawn with “milky spore” to control the grubs and adult Japanese beetles.
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<p>To get rid of Japanese beetles next year, treat with Milky Spore now; to get rid of Japanese beetles on your roses now, prepare a solution of dish soap and water. Knock the beetles off the roses into the water, plant by plant.</p>
<p>Agreeing with dmd above. I drop them in a cup with some baby oil. Strike at dawn when they are slower.</p>
<p>OPs problem is that the beetles are too high up in the tree to knock off. I wonder if taking a strong hose to the top of the tree would help. I have also used milky spore with great success, and this year I’ve only a few on my contorted filbert. My method has actually been to prune off the eaten areas - bugs and all, which removes the unsightly leaves. I’ve noticed when a plant has few or no beetles, other beetles seem less inclined to attack the plant.</p>
<p>
Is that like the Whomping Willow at Hogwarts (ala Harry Potter)? 
My apologies, Gourmetmom, the name just makes me laugh.</p>
<p>*Is that like the Whomping Willow at Hogwarts *
much smaller- It also goes by Harry Lauder’s walking stick, which does have sort of a Hogwarty sound to it.
I have a native hazelnut/filbert ( corylus cornuta) that isn’t contorted, but I do have two contorted flowering quince that I just love.
( my favorite plants are prickly!)
[Shrubs</a> with a Twist](<a href=“http://www.gardeninggonewild.com/?p=10734]Shrubs”>http://www.gardeninggonewild.com/?p=10734)</p>