One man’s Green Hour Scolia Dubia Meets Beetle ManiaBeing outside offers many experiences. Here is what NWF Chief Naturalist Craig Tufts has to say about the Digger Wasp and its relationship to garden-eating beetles at his home.
KC“Just about everyone who gardens in our area has complained about the numbers of Japanese beetles this summer. I have also been plagued by "green June beetles.” Both ate most of our raspberries and damaged our peaches. Not only do both adult beetles chew up an incredible variety of plants, from roses to grapes to Virginia creeper and many fruiting trees and shrubs, their grubs spend all fall until frost and then again next spring before early July chewing up the roots of our lawn grasses, ornamentals and shrubs.
But look a little closer in local meadows full of goldenrod, the white "eupatorium" and many tall grasses. You are likely to see a striking pollinator among the blooms. It's red; it's yellow, it's black; it's blue. It's a wasp! Sometimes called a Digger Wasp but not having a widely accepted common name, Scolia Dubia, is busily picking up pollen and nectar and (for us gardeners) it is also parasitizing recently hatched, subterranean green June beetle larvae. Some of this wasp’s' less showy relatives are doing the same to Japanese beetle larva. Come next summer, the beetles will be out again but knowing and accepting these wasps as allies in our habitats and keeping the pesticides out of our landscapes will ensure that their young will do the job and reduce these pest beetle populations.”
