by Rick Brandenburg, Turfgrass Entomologist
Credit for these pictures goes to Monte Johnson Univ. of Kentucky
The past few weeks have seen an apparent awakening of a very common turfgrass pest in North Carolina. The green June beetle is a common sight in July and August as the large metallic green beetle flies around over the turfgrass. At this time of year it lays its eggs and the small grubs feed peacefully on organic matter and turf roots. By late August and during the month of September the grubs are large, often nearly 2 inches long, and begin creating noticeable mounds and tunneling. This is unsightly and can damage the turfgrass and create drought stress. The large grubs are often noticed in the morning on sidewalks, in car ports and even in swimming pools.
This year the presence of green June beetle grubs was not as noticeable due to the drought. In areas that have received some rainfall, they have "suddenly" appeared working near and on the surface. They have not just suddenly appeared, but rather the increased soil moisture has enhanced surface activity. Depending upon the fall weather, these grubs could stay active until almost Thanksgiving. They are relatively simply to control with the application of a contact insecticide such as Sevin (carbaryl), but one must keep in mind that controlling them at this time of the year will result in large numbers of dead grubs on the turf surface. They die at night on the surface rather than down in the soil. This may leave a significant mess. Preventive treatments can be successfully used in July with our recommended white grub insecticide.