Southern and northern masked chafers are probably the small tan beetles that you see skimming over turfgrass or flying toward outdoor lights at night. Active from early June through July, the beetles are mating and laying eggs that may lead to turf damage from white grubs in August; however, the beetles themselves do not feed. Similar in appearance (Figure 1), the two species partition the night: southern masked chafers fly from around dusk until about 11 pm; northern chafers take wing after midnight. Cruising males make low-level flights over turf to detect sex pheromones released by females waiting on grass blades. Mated females will burrow into the soil to lay their clutches of eggs.
If you are seeing significant beetle flight, there is still time to apply an insecticide for white grub (Figure 2) control using one of the preventive products listed in Insecticides for Control of White Grubs in Kentucky Turfgrass (Entfact 441). However, do not make an application when soil is saturated soil; allow about 24-hours for the water to percolate through the soil.
By Lee Townsend, Extension Entomologist