I killed two huge wasps this morning on my green fennel. The first one was eating a small caterpillar and I think the second one was doing the same. I killed them by squishing them between my palms. I did it very quickly, so they had no time to react and didn't sting me. It took several times, however, and the second one I had to trap and the step on.

I hated doing it. I know wasps have a right to exist like anything else and they are beneficial in many ways, but I just couldn't stand there and watch them eat the caterpillars.

I don't know what kind of wasps they were, but they were big, more than a inch long. Looking for them on the Internet the closest likeness I can find is a cicada wasp.