I changed this bag on the Japanese Beetle trap yesterday morning ... this represents the volume of beetles that were trapped in this spot in the last 24-hours.
I had trouble finding traps earlier in the season (I saw this season's first beetle on June 7). When I did find them, I didn't put them out right away. I had been keeping beetles pretty well under control with my morning routine of picking and drowning them in a bucket of soapy water, or so I thought. Over the weekend, I realized that 'American Pillar' (my rose that grows up into the cedar tree) was covered with beetles and a majority of its leaves were eaten into lace. Picking these off would be impossible, I refuse to apply any sort of insecticide in the garden, and leaving them alone wasn't an option that I was comfortable with.
On Monday, I placed this trap about 50 feet upwind of 'American Pillar' ... figuring that I could lure the beetles from the rose to the trap that way ... and it seems to have worked! 'American Pillar' has almost no beetles on it, and this is the second bag that has filled in the last three days (the first one was full to the rim before I noticed it).
Many people will say that traps like this lure more beetles to the garden than would have found it otherwise. Properly placed, this hasn't proven to be the case for me this year or in the past. I figure it this way ... beetles I trap (or drown) are beetles that are removed from the breeding pool. I may not be making a huge dent in overall beetle population, but at least I'm doing something ... and I'm not poisoning my garden in the process.
Edited to add: As soon as I finished this post and hit 'publish', I went down to the garage to get a replacement bag for this beetle trap, only to discover that I was out of them. Since I had to leave home and go to town for replacement bags, I decided that I might as well take my shopping list with me and combine trips. Left home at about 11:30, returned just before 3:00. By that time, the existing bag on the trap was full to the point of overflowing.
To deal with it, I had to carefully put a trash bag around the trap, shake the overflowing beetles to the bottom of the trash bag, all the while trying not to gag as I was releasing the trap's bag from the yellow fins that hold it.
A new bag is installed on this trap, and I placed a second trap nearby to catch even more of the little devils.
Catching and disposing of so many beetles like this in such a short time is strangely, sadistically satisfying.
49 minutes ago