June Beetles/May Beetles/Chafer

Family: Scarabaeidae

Description

June beetles also called May beetles or Chafer are oval, stout, and12 to 25 mm long, reddish brown without patterns such as spots or stripes, and rather hairy beneath. June beetle larvae, called white grubs with cream-colored bodies and brown head capsules are C-shaped, and about 25 mm long. They have three pairs of legs, one on each of the first three segments behind the head, and live in the soil.

Life Cycle

June beetles have two to three-year life cycles. Adults emerge in late spring and are active in the evenings.  Adults mate and females burrow into the soil to lay between 50 and 200 eggs.  After hatching from eggs, white grubs feed on plant roots.  Over the course of the next two years, larvae pass through three stages becoming larger and more destructive with each stage.  In the late summer and fall of their second or third year (related to the species and climate), larvae begin pupating in the soil.  Adults emerge the following spring.

Damage

June beetles are pests of turfgrass, ornamentals, Christmas trees, cranberries, and many vegetable and field crops.  While adult beetles eat plant leaves and flowers, grubs are the most damaging life stage of the insect.  They damage plants by feeding on their roots and disrupting the uptake and transport of water and nutrients.  Initial symptoms of grub damage appear as yellowing and wilting of foliage, as well as stunting of plants.  Grubs can kill small plants but have less effect on larger plants with more robust root systems.  When high populations of grubs occur in turfgrass, discolored patches of loosely rooted turf appear in late summer.  Animals such as skunks, raccoons, turkeys, and sandhill cranes may dig and forage for grubs, causing even more damage to the turf.

Biological Control

Advice

To minimize June beetle damage, keep plants healthy and vigor through proper irrigation, fertilization, and other practices.