If you put the traps out, you WILL have more beetles. We learned the 'hard' way to let our unsuspecting neighbors get the traps - and now we barely have any beetles on our bushes. They do go in cycles though, just like all of nature.
They are wired to fall if touched by something (like a predator), and then re-climb up into the desired food source. We take a 5gal bucket, put about 2" water in the bottom, then put the bucket under the section of bush we're trying to clear. Start knocking them off into the bucket, branch by branch. If you start at the higher branches and work towards the ground it works more efficiently (gravity). Move bucket operation to other side of bush. Continue until either you're disgusted or are out of bugs....usually the first happens!
Our hens have learned to eat the bugs - but they much prefer the grubs! So do the skunks. So if you've got skunks in your yard, you've got a grub problem. We just let the hens free-range a few days about the 4th of July, and they get a lot of the creepies out of the ground before they can turn into beetles.
But get rid of the traps. They're just attracting the bugs from about a 3 mile radius to your yard. Seriously. Let someone else do that in the neighborhood. For once fertilized, the female beetle falls to the ground where she lays the eggs underneath the bush they were on. And congratulations! Now, you've got a larger problem on your hands for next year (takes a year for the beetles to mature and they eat the roots of the grass as they pupate.) So throw away the traps, they are creating more problems for you than you know....
