June bugs, often recognized by their clumsy flight and attraction to lights on warm evenings, are common reddish-brown beetles seen across North America during the summer months. They are typically 1/2 to 1 inch long. Many species fall under the general term “June bug” or “May beetle,” appearing primarily from May through July.
Adult June Bug’s Menu
Adult June bugs primarily consume the foliage of trees, shrubs, and plants. They are nocturnal, feeding on leaves at night after spending the day hidden in vegetation.
Their diet includes deciduous trees such as oak, walnut, and maple. They also consume leaves of fruit trees like apple and peach. Some species may also feed on flowers or crops like corn, small grains, potatoes, and strawberries. Green June beetles feed on the foliage and fruit of trees, including figs.
Adult June bug feeding generally results in less severe damage compared to their larval stage. While they can create ragged or irregular holes in plant leaves, the impact on healthy plants is often minimal unless their populations are very large. They typically do not consume enough plant tissue to extensively harm established vegetation.
The Grub’s Underground Feast
The larval stage of the June bug, commonly known as white grubs, spends its time underground and primarily feeds on the roots of grasses and other plants. These grubs are C-shaped with creamy white bodies and brown heads, growing up to an inch long. Their subterranean diet also includes decomposing organic matter found in the soil.
Lawns are particularly susceptible to grub feeding, as they consume grass roots. This root damage prevents the grass from absorbing sufficient water and nutrients, leading to noticeable brown patches and thinning areas in lawns. In severe infestations, affected grass may feel spongy underfoot and can be easily lifted, much like a piece of carpet, because the roots have been severed.
Grubs also feed on the roots of various garden and ornamental plants, including vegetables such as potatoes, carrots, corn, and strawberries, as well as young tree seedlings. The most significant damage often occurs during the grubs’ second year of development, as they require more food for growth. These larvae can remain in the soil for up to three years before transforming into adult beetles.