The term “June bug” is a common name that refers to many different species of beetles within the genus Phyllophaga, which is also frequently called the May beetle. These insects are part of the family Scarabaeidae, known as the scarab beetles, and are prominent across North America, where over 400 species exist. The name comes from the timing of the adult stage, as they typically emerge from the ground in late spring and early summer, often coinciding with the month of June. They are a familiar sight and sound during warm evenings, characterized by their buzzing flight around outdoor lights.
Defining the June Bug
June bugs are relatively robust and heavy-bodied insects. They generally range in size from about half an inch to one inch long (12 to 25 millimeters). Their coloration is typically a dark reddish-brown or chestnut brown, and they possess shiny, hardened forewings called elytra. The name Phyllophaga itself is derived from Greek words meaning “leaf eater,” a reference to the adult beetle’s diet.
Understanding the Life Cycle
The life cycle of most June bug species is lengthy, typically lasting three years from egg to adult, although some species can complete it in one or two years. The adult female lays 15 to 20 small, oval, white eggs in the soil, usually in grassy areas or near trees during the late spring or early summer. These eggs hatch after a few weeks into the larval stage, commonly known as white grubs.
The white grub is the stage that spends the longest time underground and is responsible for most plant damage. These larvae are C-shaped, have a whitish body with a brown head, and feed voraciously on the roots of grasses, ornamental plants, and various crops. In autumn, the grubs migrate deeper into the soil to overwinter, returning closer to the surface to feed again the following spring. They progress through three stages, or instars, before pupating deep in the soil.
The grubs transform into adult beetles within the soil, remaining underground throughout the winter. They emerge as mature, flying adults only when the soil warms up in late spring or early summer, ready to mate and restart the cycle. This synchronized emergence in certain years can result in a notably large population of adult beetles.
Behavior and Interaction
Adult June bugs are predominantly nocturnal, active after sunset. Their presence is often announced by their clumsy, buzzing flight, which is erratic and heavy. This buzzing is commonly heard as they fly around bright porch lights or streetlights, exhibiting a strong attraction to artificial light sources.
Adult beetles feed on the foliage of trees and shrubs, including oak, maple, and hickory leaves. While they can cause some defoliation when present in large numbers, the damage is generally less severe than the feeding activity of their larval stage. As both grubs and adults, June bugs serve as a food source for various animals, including birds, raccoons, skunks, and moles.