Black turfgrass ataenius adults are dark brown or black and about 1/4" long. Adults over winter in loose soil, pine needles, and leaf litter and begin moving into turfgrass in March or April. Females deposit eggs in soil and thatch. Upon hatching, the larvae feed on grass roots for 3 — 5 weeks before pupating. Most first-generation adults emerge in mid-July.
Second generation larvae begin appearing in late July or early August and mature into the over wintering adults by October. Black turfgrass ataenius larvae are almost identical in appearance to other species of white grubs, but are much smaller (1/4"). Accordingly, larger numbers of these grubs must be present before severe turf injury occurs.
The Black Turfgrass Ataenius beetle has been reported in every continental state except Nevada and Montana. Gradual turf thinning in enlarging patches that turn brown; roots pruned to 1" or less below soil surface; sod is easily lifted or rolled back; C-shaped white grub larvae found by lifting sod; adults of most species are active at night, but do not feed on grasses.
Black Turfgrass Beetle feeds on roots of annual bluegrass, bentgrass, and Kentucky bluegrass.