Many people respond negatively to wasps, but not every wasp is to be feared or eliminated. As a gardener, the presence of the great golden sand digger wasp (Sphex ichneumoneus) should be celebrated. These non-aggressive wasps provide natural pest control for the garden. While the adults are pollinators eating nectar and pollen, their young are provisioned with katydids and grasshoppers, the gardener’s foe. Females dig several tunnels, each with one to seven brood cells. In each cell, she lays an egg on one paralyzed prey insect and adds several more for future food. Once her eggs are laid, she covers the tunnel and leaves her offspring, not concerned with defending her nest. Females can capture insects equal to and sometimes even twice their body weight. They drag the prey or, if it is very large, climb vegetation and launch themselves toward the nest. Birds often chase these wasps in the hope that they will drop their prey. Beyond pest control, the tunnels these wasps dig benefit the gardener by facilitating soil aeration and water movement. They are also fascinating to watch. We found this wasp during summer camp and very much enjoyed watching her dig her nest.
Female Great Golden Sand Digger Wasp. Note the hole to the far right and the line of dark colored soil drops where she has been excavating
Sue Watts, ©2024 SC Botanical Gardens, Clemson University
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