There are many species of june beetles - the four types most commonly found in the San Diego area are the following: 

• Sericas (Serica species, subfamily Melolonthinae)
  These beetles are small to medium sized (1/4 to 3/8 in., or 6 to 10mm), cylindrical, and usually smooth and hairless.  The wing covers are tan to black with faint longitudinal lines.  The most abundant species seems to be Serica alternata.
• Hairy June Beetle (Phobetus comatus, subfamily Melolonthinae)
  This species is hairy and medium sized (its length is 9/16 in., or 15mm); the body is generally grail and soft, and the wing covers are pliable and translucent.  Larvae feed on the tree roots that are just below the surface.  Adults are present during the spring (March and April).
• Dusty June Beetle (Parathyce palpalis, subfamily Melolonthinae)
  This medium-brown beetle is the largest of the four (its body length is 3/4 to 7/8in., or 20-33mm).  Its upper surface is coated with minute elongate white scales, its undersides with white hairs.  If the beetle is handled, the scales are easily dislodged in patches, giving it a smudged or blotchy appearance.  The heart-shaped scutellum is noticeably paler tahn the rest of the back.
• Cyclocephalas (Cyclocephala species, a subfamily Dynastinae)
  Species in this genus, such as C. hirta, are very common locally.  They are medium-sized (the body length is 1/2 in., or 13mm) and pale tan, some with fine specks or lines along the back.

Hosts
Grubs are pests of grasses and some other tender young plants. Adults damage fruits, grapes, and flowers.

Damage
Adults are considered a serious garden pest feed on ripe fruits of several types, including peach, fig and grapes. Occasional damage to other fruits and flowers also occurs. More serious damage is done to pastures and turf grasses by the tunneling of both adults and grubs, which disturbs the roots and increases drying of the soil in the root zone. June beetles are destructive lawn pests.

Life Cycle
Adults emerge in early summer. They are active in the daytime, feeding and flying over grassy areas in search of egg laying sites. They return to the soil each night. Eggs are laid in the soil, mostly in June. Grubs spend the day in the soil, emerging at night to feed at the surface on decaying organic matter. A new tunnel is dug each night to return to the soil.

Control
Control with a variety of common insecticides is very effective for both grubs and adults.

Call Adios Pest Control for Pest Control in San Diego and throughout San Diego County; we provide pest control services 7 days a week.