I thought I would start a thread for these dreadful pests.
I came upon a photo on my phone from last year on June 24 of a pile of japanese beetles on a wild grape plant. So they are coming soon to my neighborhood. But I checked my roses and none of the pests are there yet.
Our state extension says 1030 GDD(50) since January 1 is the typical first emergence for JB. http://crops.extension.iastate.edu/cropnews/2017/06/japanese-beetles-emerging-southern-iowa
Are you seeing JB’s this year?
There are always some around in my yard. BT seems to work well.
I noticed them for the first time yesterday on my sweet cherries. They definitely prefer cherries over all other fruits. I don’t remember when they showed up last year but I assume around the same time. Time to get the carbaryl out.
Do you use the standard Bt kurstaki strain stuff?
I know there is a Bt galleriae strain sold for an significant price ($25 for enough to make 1 gallon) by Gardens Alive that is supposed to be more effective against JB’s.
I had a few on a small Stella cherry tree I noticed yesterday.
If I recall they didn’t get here last year until right about the time I was finishing up with my cherries, so they may be here a tad early this year if I’m remembering correctly.
Yep…just like some of you, I saw my first ones this week. As @speedster1 said, they definitely go hard for cherries. The only thing they like more at my place is grapes. It’s mind blowing how much damage they can do to grapes and young cherry trees in just a day or two! And as Dave said, I find liquid Sevin to be far and away the best weapon I have. AS impressed as I’ve been with imidan for most bugs, it doesn’t do that well against Jap Beetles.
I just swished the first one on my Jujube tree today. Time to take out the Sevin dusts.
Tony
They were on my muscadines a few days ago. Sprayed with a mixture of surround/neem. I haven’t seen one since the spraying.
How I hate them!
They usually show up here around the first of July, fortunately after the cherries are done, upon which I hit the tree with systemic pesticide.
After cherries, they like plums, and I’ll wrap my new Brooks in netting again
It’s ‘normal’ as far as I know. I flicked a few off my fruit trees that seemed paralyzed, but I suppose it’s possible they weren’t. Haven’t seen much additional damage yet.
Thanks, I might hit them with spinosad + Bt and Surround as a deterrent. Let them deal with two toxins at once. Surround this time of year is hard to keep up with especially on the plums, where it seems it doesn’t stick well.
I get them here right after the 4th of July. We don’t have grapes or cherries so their preference for our stuff in order:
Here comes one of my famous dumb questions, but what is Bt?
No not dumb, but rather calling out jargon!
Bt is Bacillus thuringiensis bacterium, its spores, and the proteins it produces. The proteins are toxic to certain insects.
The typical Bacillus thuringiensis is the kurstakii strain (product names Dipel, Thuricide, etc.). That strain is most toxic to worms (moth larvae).
There is another strain - Bt galleriae - that is more toxic to japanese beetles and beetles in general. However, that product is $25 for enough to make 1 gallon of spray!! And always sold out in larger quantities.
Bt formulations aren’t toxic to humans and are organically acceptable. As with some other organically acceptable insecticides, the target activity is specific to certain insects. (See also spinosad.)
Most GMO corn has been genetically engineered to add the genes from Bt bacteria that encode the biological synthesis of the toxic protein.
BT paralized another 5-6 japanese beetles that I found on my cherry today after work. I didn’t see any others around, and none of the other trees show damage, so it seems to be working.
BT hits most/all? leaf eating insects. I don’t think it affects the bees/wasps that carry away leaf bits for hive construction.
This is an example of how devastating they can be. I took this picture when I got home from work today. I didn’t have an opportunity to dust yesterday and this is what happened. Both cherry trees got rocked. Nadia, Emerald Beaut, methley and my pluots all got hit to some degree. But none nearly as bad as the cherries. I only had half a container of Sevin. Ill have to stop tomorrow and get a few more canisters.
Black Gold cherry. Look at the leaves on the lower part of the tree
A couple good shakes of the cherry tree.
Damn it! My pictures keep rotating after upload. Anyone know why?
I use the traps. They work pretty good but also attract them to the area so put them on the perimeter of the yard. I also have a ton of trees so they havent really chosen any one more than others.
This fall I’m buying milky spore. Even though it costs an arm and a leg.
Speed,
Sorry for the damage. Milky spore will work well in your area. When I used it 6-7 years ago, I call their hot line asking about the temp. They said it is not as effective in very cold zone. At the time mine was zone 5 b.
So am I. I plan on using it the next 2-3 autumns.
