How many generations do Japanese Beetles typically have in a year?

Japanese Beetles typically have one generation per year. This life cycle begins with the adult beetles emerging in the summer, usually around late June through July, depending on geographical location and weather conditions. After mating, females lay their eggs in the soil, which then hatch into larvae (grubs) that develop through the late summer and fall. These grubs overwinter in the soil and pupate in the spring, giving rise to the next generation of adult beetles.

The one generation cycle allows for a concentrated emergence and mating season, thus facilitating easier management of their populations compared to pests that have multiple generations in a season, as these can lead to overlapping life stages and more sustained damage to turf and garden plants. Understanding this cycle is critical for effective pest management strategies, like timing treatments for grubs or adults.