Grass Sawfly Wasps
Grass sawfly wasps are among the first insects to appear in spring. They often chose to rest on light-colored surfaces. Grass sawfly adults are shiny, black 3/8-inch-long insects (Figure 1) with thin black antennae about as long as the body. Two pairs of clear wings lay flat over the back.
In spite of the name, sawfly wasps cannot sting and pose no threat. Soon female wasps will be laying eggs in grass and caterpillar-like larvae will feed on grass blades. Grass sawflies are rarely present in damaging numbers. There is no need for control.
Boxelder bugs (Figure 2) are beginning to move after spending winter clustered in protected places. These common insects feed on sap from leaves, twigs, and seeds of boxelders and other members of the maple family. Large numbers of them can be seen on tree trunks, on branches, or sunning themselves on buildings in spring. These harmless accidental invaders may be a temporary nuisance as they move out of sheltered overwintering sites. Vacuum or sweep up and discard those found indoors. Swatting them will produce an unsightly stain.
By Lee Townsend, Extension Entomologist