10,000 Predatory Wasps

WARNING! This building is home to more than 10,000 predatory wasps. Enter at your own risk.

That is a sign for a greenhouse. Most everybody I've told about it has cringed at the thought. Wasps bring nightmares to most of us because they are aggressive and it hurts when they sting. But when I tell another Master Gardener about this sign they yawn and smile. At best they congratulate me. But then, they know the meaning of the term "predatory wasps".

The wasps most people think of when they hear the term is the paper wasps and hornets that most of us, me included, tend to run from when we see the...