Oh, my! It looks like 2015's going to be a doozy of a year for Japanese beetles around here! I'm removing sod and digging deep to build a modified French drain while simultaneously constructing a new hugel bed, and the JB grubs are the most numerous I've ever seen!
I guess it's time to invest in a pair of spiked shoes and start stomping.

The Japanese Beetles may be hanging out with other types of white grubs. Good luck getting rid of them all.
http://www2.ca.uky.edu/entomol...

If it's at all possible, get yourself some chickens (banties are miniatures that are a good choice for suburban homes) and let them free range as much as possible (or keep them in a movable pen). I used to have a terrible problem with Japanese beetles until we got hens....now the beetles are a rare sight. The same seems to apply to stink bugs. A few years ago, they were terrible until the hens got a taste for them. Now, only a few.

The chickens don't actually dig up the grubs (they're usually too deeply buried), but they seem to have an uncanny knack for knowing exactly when the grubs emerge as adults.

I happen to have saved this article: http://www.greatbiggreenhouse....

because it recommends a spray that (it says) is certified organic and, along with picking and a September application of something called Milky Spore, is said to work well.

I am not speaking from experience, just sharing what sounded to me like a sound and relatively benign control strategy, if one has no free range poultry.

Our one and only neighbor has free range chickens, so whether we want them or not, they're here, too. Now, if the help with grubs balances out against the destruction of spring seedlings...good enough.

I haven't read the article yet, Kyla, but thanks for posting it. Hopefully I'll have more reading time later this evening. It's so pretty out that we're off to ride bikes for a bit.

Maybe a mini-sprayer irrigation system wired to a motion sensor would keep seedlings moist AND deter chickens while the seedlings are small.

Kyla,
That article suggests dealing with very heavy Japanese Beetle infestations with a spray containing Spinosad. That seems to have very low toxicity to mammals, and relatively low toxicity to pollinators after it dries for a few hours.

Also, it is so different from other insecticides that it doesn't seem to have any cross-resistances with them. Thus insects that have developed resistance to insecticide A,B and C won;t have any resistance to Spinosad. And insects that are resistant to A, B and Spinosad won;t have resistance to C. If farmers alternate insecticides cleverly, insects tend to only develop resistance to the insecticide that you used LAST year, and loose much of that resistance before you get around to re-using one.

I think the best news is that it breaks down very rapidly in the soil.

http://en.wikipedia.org/wiki/S...
http://www.ncbi.nlm.nih.gov/pu...

The link also talks about Milky Spore - read a bit further to see that part.

Yup. That, I am quicker to believe is benign to the environment.

Spinosad SOUNDS good, but I was suspicious when I read "derived from natural products". That's no guarantee of "green-ness". But it does sound good.

I'll still more comfortable with just hand-picking them. Some years are just worse than others. Our last two or three summers were fairly low population-wise; next summer's just not going to be one of them. That's okay, though, high and low cycles are natural.

We had very few Japanese Beetles this year. I'm going to put out more Milky Spore. Apparently that spreads itself around quite nicely.

Unless the procedure has changed dramatically, Milky Spore has to be applied to every square foot of ground, and it takes repeated applications, year after year, to be effective. Then comes the problem of the JB's flying in from your neighbors' gardens. Unless you can convince every neighbor to apply it you'll still have them.

Milky spore can be applied using a drop or broadcast spreader. The beetles inject it after which the milky spore multiplied inside each insect and as the beetles die the Milky spore increases and spreads. If you are friendly with your neighbors and can coordinate it, you can each treat your own property and within a few years the Japanese beetle problem will lessen. This is not a quick fix but it is one of the things that is safest for the environment and safer for the beneficial insects.

Good information here:
http://web.extension.illinois.... The person who wrote this explains how to apply the Milky spore powder - with a spoon in a grid pattern (ooh, too tedious for this old girl). Also covers the question of neighbors who do not use Milky spore - in short your moles will leave and head for your neighbor's yard to eat at least until your Milky spore migrates over the property line.

The following link shows a product that can be applied with a drop spreader or hand held broadcast spreader. It needs to be applied 3 times during the year for 2 years, but considering that will control the Japanese beetle problem for about 20 years, it seems to be worth a bit of extra effort.

http://www.domyownpestcontrol....

We've done it and tedious is right.

How many neighbors would want to spend the money when so many do not have gardens, nothing in bloom at all? They have shrubs and trees, beautiful properties but they just are not gardeners. I doubt many of our neighbors would even know what a Japanese beetle is or be aware of the damage they do. We do not have moles so there is no "head for your neighbor's yard".

It's a major undertaking with iffy results.

Milky Spore also comes in a dispenser tube which makes the process easier, IMHO.

My neighbors have "nothing at all" in bloom. They removed everything with a flower. Oh well.

"Easier" for the first 50 square feet...maybe. That's if you have a strong back and great knees. I've done it for one garden (by myself) and it's tiring and boring. Doing it daily for 5 hours a day would really be boring!

Some neighbors have a row of begonias while another has impatiens. How creative! Still, they do care for their properties so it's their choice. They love golf, playing Bridge, etc. so who am I to complain?

I am not trying to discourage people from finding solutions but it's nice to be aware of the huge job it is to spread the Milky Spore. The spreader sounds good but then comes the issue of roses, perennials, shrubs, trees, etc. where it can be impossible to use a spreader. I do wish there was a spray but it hasn't come along yet.

An entomologist at a turfgrass conference I attended didn't think milky spore was worthwhile. Quoting from a Cornell University article, "..... a recent field study in Kentucky showed that commercial formulations of P. popilliae (milky spore disease) were only moderately infective (39-44%), that infected grubs consumed the same amount of roots as uninfected grubs, and that lower grub populations could not be linked to infection. Researchers concluded that earlier reports of success were limited to very high infestations of grubs where other stresses may have increased their susceptibility to diseases." This is from:
http://www.biocontrol.entomolo...

In the talk I was at, the beneficial nematode Heterorhabditis bacteriophora was said to be a better choice among the organic treatments.

Another problem with milky spore is that it only targets Japanese beetles, whereas there are many other kinds of related "white grubs". You can tell the difference between these grubs by looking at the raster spine arrangement on their bottoms and comparing with diagrams of the spine pattern, but getting them to stay uncurled while peering at their posteriors can be a challenge, especially with the smaller ones. Here's one such guide to raster patterns:
http://www.msuent.com/assets/p...

lol. Please don't shoot the messenger just because you don't agree with something. Different people's experiences are just that - different. My experience has been fairly successful as I have eliminated most of the Japanese Beetles in the yard ... and I am very pleased about that.

I don't think we're shooting the messenger but we are trying to alert people that it may not be the answer for them.

The JB's must make their travel arrangements long in advance since they arrive here every July 3rd. So, by the end of June, I cut off every rose bud in the high hopes that when they don't find their favorite dining spots they'll move on and lay their eggs elsewhere. All of us who fight this menace try to do the best they can to stop the invasions. All we can do is try.

If I knew you were ready to apply the Milky spore I would have given you my back saving tip. Too late now, but it may help others.

Get a medium to large size funnel - look in the auto supply department for inexpensive funnels. Cut a length of PVC pipe, for me 42 inches is a good working length. Place the funnel into the PVC pipe (that's the top end) with the bottom end near the ground where you want to apply the Milky spore. This works better when there are two people, but I have done it by myself. Place a teaspoon of the Milky spore in the funnel and it will conveniently drop through the PVC pipe. Easy-Peasy. If you really want to look like a dork you can rig up something to attach the PVC to your waist which allows you two free hands for working.

When someone asks me to apply ant killer on their property I use this same method to apply the product only to the ant mounds rather than broadcast huge amounts of poison all over their property.

I have been toying with the idea of using an old golf bag cart to improve this idea. If it works it can be rolled around the property.

Good suggestion about the golf cart bag, greene. I hope it works.