I've applied beneficial nematodes and milky spore a few years running now, but based on the look of my poor roses when I returned home tonight, I don't think I'm even making a dent in the population.

I had hundreds of those pretty beetles crawling in and around the rose blossoms. I promptly filled up a few containers with ammonia and started tossing in my rose blooms. It is now sitting in the afternoon sun (top closed), stewing the poor little buggers.

Is there anything else I can do to rid myself of the hoard? Do the roses actually attract them to the yard, or just give me a good "trap" to find them. (I'm wondering if I should rip out my roses... I'm ready to if it would help...)

They do make pheromone traps for Japan beetle.

Keep on picking them off and drowning them.

Dont'cha just love introduced insects?

If you own a shop vac, you can suck them up... my yard is infested with shield bugs. They come around with the ripening fruit and they are all over. I've been vacuuming up spiders from my porch and when big bugs walk by they get sucked too. Hard bodied insects are hard to kill with any sort of purchased organic product, in my experience, but squishing or sucking works great.

The Japanese Beetle "traps" have an attractant that lures the adult Males tothe trap where they, the adult males, release a phromone that lures in the female adult beetles, so the "traps" are lures and donot belong in your yard much less your garden. Even if you did eliminate all the grubs, the larva of these beetles, from your yard and garden you would have them because they come from many places and are attracted by a wide variety of plants.
The best defense against them is to grow your plants in a good, healthy soil that has a well balanced nutrient supply and the pH in a range the plants prefer, ie grow strong and healthy plants that are better able to withstand these insect pests.
There is a large body of research from, among other Dr. Phillip Calahan, that indicates insect pests are more attracted to plants under stress then they are to plants growing happy and healthy.

I just started noticing the japanese beetles this year. They're on my bean plants, dwarf apple tree, plum tree and grape vine. I have been going out there a few times a day with a bucket of soapy water and tapping them in there. They appear to no longer be on my apple tree, and rarely on my plum tree. They still make daily appearances on my bean plants, and I'm still working on getting them from coming back so much to my grape vine.

I did read on the internet somewhere that when they are on a plant, they attract others to the same plant. So physically tapping them in soapy water is supposed to keep too many from being attracted to your plants.

When my friend set up a beetle trap, she ended up attracting ALL of the Japanese beetles in the area. It didn't make things better for her.

I would plant something that those bugs find more (or just as) appealing, like zinnias, shasta daisies and ironweed:

http://2bnthewild.com/plants/H66.htm.

Raspberry would help too.
Your roses will still be attacked, but not necessarily as much.

1) Traps are something you give to your neighbors. Saw your beetles go over there

2) One of the interpreters (I think in the herb garden...) when I was at Old Sturbridge Village yesterday mentioned they often used raspberries as a trap crop to attract the beetles. Of course, they had plenty of kids to go out with orders to squish the beetles then

So maybe your roses are the sacrificial lambs that keep them from eating other stuff on the property.

3) If you must use traps...I love this guy's modifications to make the ultimate beetle trap (Scroll down, can't miss the pictures!) http://ytforums.ytmag.com/viewtopic.php?p=1705473&sid=3...129e84338251f489616b

If you the only one doing something in your neighborhood... and even town, then it's money down the drain. Hand picking off your plants is best method and also planting diversions could help.

Traps will only attract more.

Easiest method of control is a small container of soapy water. Go out in the AM and brush them into the soapy water and poof they are history! On ornamentals try Safer Soap spray.

The milky spore dust worked well for me. I applied it late in the fall...I had a terrible infestation last year. I will apply more this year. Did you do the garden and the lawn?

The Milky Spore Disease powder is nto something that you would, necessarily, need to put down every year because if you did an adequate coveage the last time there will be more disease spores in your soil now, from those grubs that ingested the spores and died from the disease, then what yo put down back then.
Often, because of the cost, people will cover one area of the yard one year and another area another year.

Hello Ladog,

What have you tried that worked?

Wayne

For 3 years straight, I had Jap beetles everywhere. Got 6 of the traps/bags and spread them over about 2 acres. I had to change bags pretty often the first year, second and third years not as often. This year, I did not put them up, and I have not seen the first Jap beetle. My neighbor on the street below me, about 1/4 mile away as the crow flies, said everything at his house was covered with them. I'm betting that because they got trapped, they had not mated yet or laid their eggs, so, I'd put my money on the traps. The first year is the most expensive, but after that you only need to buy the bags and the bait. I actually used my bait two years in a row. I put them in plastic bags at the end of the season. Also I cut some in half which worked just as well as the whole disk. Since I'm rather frugal, I started making my own bags by using the original as a template. I used heavy duty plastic and clear packing tape. Worked fine. I probably should do the milky spore as a precaution, because they will be back, just not this year.