Hickory Bark Beetle (Scolytus quadrispinosus)
Latin Name: Scolytus quadrispinosus
Common Name: Hickory Bark Beetle
Appearance:
The adult is a small, 4- to 5-mm long, robust, densely cylindrical, black to reddish-brown beetle with nearly little hair. The front tibia has a short bent spine or hook.
The male ventra is severely dug; the third abdominal segment has three spines, and the fourth has one big central spine.
The female ventriloquy lacks spines.
The egg is ellipsoidal, cream in color, and scarcely visible to the human eye. When grown, the larva is small, bent or slightly C-shaped, legless, yellowish-white, and 5 to 8 mm long. The body is wrinkled.
The pupa is small, delicate, and white.
Host plants:
Shagbark hickory (Carya ovata), Bitternut hickory (Carya cordiformis), and Pecan (Carya illinoinensis).
Territory:
Native to eastern North America.
Damage caused by Hickory Bark Beetle:
Adults feed terminal growth while larvae burrow in trunks and big branches. Throughout the summer, newly emerging adults graze on crown twigs. They construct small feeding tunnels in twigs, primarily at the base of axillary buds and leaves. Heavy twig feeding may result in yellowing, premature leaf loss, and broken twigs dispersed over the crown, but it will seldom substantially harm the tree. Within weeks of being attacked, the foliage of strongly infested trees becomes yellow, red, and brown as the tree succumbs. Trees that are stressed and weak due to drought, fire, storm damage, disease, or other reasons are the most vulnerable.
Life history and Habits:
Adults emerge in early summer, feeding at the bases of leaf petioles and twigs before attacking the stem. In egg galleries, 20-60 eggs are laid. They exit the phloem to pupate in the bark before reaching maturity. The larval stage lasts throughout winter, while pupation occurs in the spring. Eggs are ellipsoidal in shape, cream in color, and scarcely visible to the human eye.
The larva is 5-8 mm long, small, curved C-shaped, legless, and yellowish-white. In the United States, two generations are born each year.
