Insect Injury Control

From Bugwoodwiki

Giant bark aphid,

Longistigma caryae (Harris); with relation to other aphids, this species is very large, .25 inch (6 mm) long, withlong slender legs, and is covered with a bluish-white "bloom": several generations per year. Terminals, twigs, and branches of red and white oaks; aphids feed by sucking the plant sap; heavily infested stems badly weakened or killed; honeydew and sooty molds mar beauty of ornamentals.

Pit scales,

Asterolecanium spp.; adult females are circular and enclosed in yellowish, waxy, translucent covering, .04 to .08 inch (1 to 2 mm) in diameter; one generation per year. Found on twigs, branches and trunks of red and white oaks; prefers white oaks; maturing females produce ring-like swellings or pits on the bark causing a rough appearance; branches and trees may be killed.

Kermes scales,

Kermes spp.; adult females are globular or gall-like, yellow-brown-black, solid or mottled, about .1 to .3 inch (3 to 7 mm) in diameter. Scales occur on twigs, branches, near buds, near wounds, on leaf midribs, and petioles of red and white oaks; dieback or "flagging" of newly formed terminals, branch ends, and new leaves; early leaf drop; mar beauty of shade trees.

Obscure scale,

Malanaspis obscura (Comstock); adult female cover circular, grayish to black – resembling bark in color .08 to .1 inch (2 to 3 mm) in diameter; two generations per year. Trunks and branches of red and white oaks; infestations are often heavy and layered, killing branches, or resulting in general weakening, and sometimes death of tree.

Spider mites,

Oligonychus spp. and Eotetranychus spp.; .02 inch (0.5 mm) long, spider-like, eight legs, sucking mouthparts; large numbers often present; many generations per year. Foliage and buds of red and white oaks; scattered chlorotic stippling on leaves later yellowing or bronzing, then browning and dying of foliage; mats of webbing often present; weakens tree and mars beauty.

White grubs,

Phyllophaga spp.; larva is milky white, C-shaped, about 1 inch (25 mm) long, brown head; adult beetle is robust, oval, brown, about .5 to 1 inch (12 to 25 mm) long. Wide host range, including oak seedlings and young trees; larval feeding prunes and girdles roots; nurseries and young plantations often damaged; adults may defoliate trees.

References

J. D. Solomon, F. I. McCracken, R. L. Anderson, R. Lewis, Jr., F.L. Oliveria, T.H. Filer, and P.J. Barry