We are virtually beetle free. None at the traps now and only a few here and there, usually on their favorite plants, roses being at the top of that list. Most plants blooming now go through the entire flower cycle without being attacked. Here's a species glad from South Africa currently in bloom.

Hi Larry ,We battled these scourges much the same way as you.We have an acerage near West branch.This is the 3rd year for the beetles.
We had them just about as bad as you. They wreaked havoc on our Linden trees.Next year we will try & get a more powerful sprayer for the trees. We were looking at traps at Paul's.A lawn care guy was in there looking at sprayers. He said not to get the traps.Said Spraying with Sevin was the way to go.We bought the Sevin & returned to store same day & got 2 traps. Same kind as you have.Hubby put it together in the kitchen & they were swarming him as soon as he went out the door. I actually found 2 in the house! He located traps downwind a distance from gardens.I had Safer soap spray on hand & used this.I couldn't see it did much.Maybe I expected them to drop dead on the spot.I had a spray bottle containing soap & canola oil but didn't get results. For spot treatment of roses & cannas I found some old rose dust
in my arsenal.It is an Ortho product & I don't even know if it is available now.The shrub they favored the most is our Blue Bird Althea.Last year we had no decent blooms until after the beetles left. So this year hub sprayed it with Sevin.It helped a lot.My plan with roses was to go ahead & cut them way back & wait until beetles have left & then water & fertilize & hope for a fall show.I was told that their season has about ran it's course. Maybe by the end of this week or first of next week. I think this is true because there are a lot less of them yesterday & today.Actually a couple roses grew out & weren't covered with the devils & I think my watering washed off any dust.
It is unbelievable how many are trapped.Trap got so full that zip bottom gave out.Oh shucks! Some got away. This is easily fixed. He used several of those black squeeze together clamps to secure bottoms.Oh sure we both used containers of soapy water to kill some but with the size of our place it is a drop in the bucket.
I'm not sure a trap would be good in a small yard.You might just lure them right to your flowers.But if you put them far enough away,I swear by them.
Hubby just puts a plastic bag up onto trap & empties into this.
And as you said there are going to be a whole lot of beetles that are not going to procreate!
And yes they are worse this year. There are cornfields across the road that are being sprayed by airplane.
Always something,huh?
sewNsow

I used the Bag A Bug this year as an experiment and placed two in different areas. The bags immediately catch some beetles but I would not say we had the enormous amount caught that Larry did. Each bag is only 1/4 full. Checking the daylilies and other plants, I've caught quite a few myself with my cup of soapy water. Did the Bag A Bug work? Yes, but not a high percentage of caught beetles or the population is less this year than in prior years.

Thanks Larry for showing a very detailed picture of your bag system. Might try that next year.

Anyone use Milky Spore???

Good to hear from a fellow Iowan, sewNsow! Thanks for sharing your beetle experience with us. I think that the trap/spray combination is the way to go. I limited plant damage by spraying the bugs three times a day. The traps also served to concentrate the bugs in a small area, so that I could zap a lot of beetles with just one or two squirts every time I made my spraying rounds.

Hi Julia, thanks for sharing your experience. The traps I used--Rescue is the brand name---were a powerful lure and Bag A Bug is a similar product, so I suspect you had fewer beetles in your area this year.