RE: Results From The Japanese Beetle Trap
We've tried the trap and skipping the trap and have noticed that when we have the trap, we draw more beetles to our little orchard for far longer than if we don't use the trap. It seems like the lure draws the beetles from miles around whereas if we skip the trap, we only deal with the ones right on our property.
This year we tried spraying the trees (especially the cherries) with a neem oil and sal suds mixture and it did seem to deter them, though we still had quite a crop that I was knocking into buckets of water to drown for about two weeks (not practical with a bigger orchard). I'm going to try putting milky spore into the soil of the orchard area this year and see if I can kill off the grubs actually in the area so we don't have quite so many beetles emerging right on top of our garden and orchard next year. And milky spore once established apparently stays in the soil for many years, so would be far more sustainable than the traps/lures.
We had heard about the traps drawing in beetles from outside our property. That was one reason why we were not real sure about the traps. I have heard about a lot of people using neem oil or milky spore, and they were options that we were considering this next year. We were still trying to do some research to figure out which option will work best. Do you have to reapply your neem oil mixture everytime after it rains?
I know some people reapply every time it rains and for that week or two when the beetles are worst I did diligently reapply (I also did earlier in the spring when the cherry trees got attacked by some type of black aphid which was destroying the new growth). I think I only had to do it twice for the beetle invasion, though. I learned you can put the mixture in a hose sprayer and set the dial, allowing you to do a lot of trees very quickly.