I forget to share that there are some really potent garlic sprays that work too. We have tons of humming birds so I am very careful of what I use.
Also...I would never allow the traps to get close to plants I don’t want the beetles on.
bump
That's the problem. Plants almost everywhere. Or too close to the street, etc. They work best in almost full sun. And you don't want them to fly over any plants they like to get to the traps. The roof might work or high in a tree they don't like, but can't get up there.
Anyway, one lady was so swarmed in central IL she couldn't go outside for awhile, heard them banging against the house. There was a newspaper article about the invasion and her. She claimed to have made a homebrew of lemon juice, vinegar, and dish soap (prob dil w/water). A couple of us tried to call her and find out the proportions but no luck. I thought I might guess and do an experiment, maybe 1/2 cup to a gallon.
I'll freepmail you a copy of the article I saved but the formatting will be bad.
I don't know if garlic would work or not. I've got that liquid fence stuff but think no. Some people blend up dead beetle cocktail and spray that, too gross for me.
If you read anything that sounds easy, fairly safe and promising, please ping me. Even laying down milky spore won't be all that easy for me, terrace, may have to do it twice or more to get it going. They will still come in from neighbors who don't do it.
Not enough people care yet in my community for there to be an effort on that front. One lady in TN trapped enough over the years, she not only helped farmers close by (they like corn silk) but this year she hardly had any. I've got instructions for a modified trap. The bags don't work that great and nasty to empty and change; bait part works several weeks.