This is a cluster of parasitic wasp pupae. The adult wasp would have laid eggs into a caterpillar to provide food for the developing larvae. The larvae develop inside the caterpillar and then exit it to pupate, usually killing it in the process. Once finished pupating, the adults will mate and search for more caterpillars to parasitize. Parasitic wasps can be attracted to fields by planting wildflowers, such as sweet alyssum, buckwheat, dill, parsley, cilantro, etc. For more information, see HGIC Attracting Beneficial Insects to Your Vegetable Garden and Virginia Cooperative Extension Parasitic Wasps.
What Is It? Wednesday – Parasitic Wasp Pupae
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