SCALES
    Scale insects belong to the order Homoptera, superfamily Coccoidea. They have piercing-sucking mouth parts and are usually sessile in their habitat on plants. There are two kinds of scales, the armored scales and the unarmored scales. The females of the armored scales are legless, wingless, eyeless, and covered with a shell of secretory material beneath which they live. The armored scales are sessile in all but the first instar; unarmored scales have legs throughout their life and do not form a separable shell over their bodies.

Black Scale (Saissetia oleae): This is an unarmored species. Adult females are almost hemispherical, about 1/5 inch across, around 1/25 to 1/8 inch thick, dark brown to black, with a longitudinal ridge and 2 transverse elevations on the back forming the letter H. Adult males are active, two-winged insects, but they are very rare.

Black Thread Scale (Ischnaspis longirostris): Adult females are very thin, 1/8 inch long, thread-like, and dark brown to black.

California Red Scale (Aonidiella aurantii): Adult females are about the size of a pinhead, 1/12 inch across, armored, circular, and reddish-brown in color. Yellow winged males fertilize a female and then die.

Cottonycushion Scale (Icerya purchasi): Adult females are reddish brown and attaches a large, compact, white, fluted mass, which holds from 600 to 800 bright red eggs. Young larvae are red with dark antennae, dark legs, and have long hairs at the end of the body. Adult males are minute, winged, and have long white filaments.

Latania Scale (Hemiberlesia lataniae): This scale is armored, circular, and about 1/16 to 1/12 inch in diameter. Sulfur yellow crawlers often appear on stems, leaves, petioles, or fruit.

Lesser Snow Scale (Pinnaspis strachani): Females are white, semitransparent, pear shaped, and may be spotted with brown from the incorporation of pieces of bark. Males are minute, elongated, white, and often so numerous that they give the appearance of salt over the bark.

Gray Garden Slug (Deroceras reticulatum): This slug varies in color from white to pale yellow, lavender, purple, or almost black with brown specks and mottling; it varies in length from 1/2 inch to 1 1/2 inches.

Greenhouse Slug (Milax gagates): This slug is dark gray to black with a longitudinal ridge down the body and a diamond shaped mark in the center; it varies in length from 1 1/2 inches to 3 inches.

Spotted Garden Slug (Limax maximus): This slug ranges in length from 1 1/2 inches to 7 inches. Smaller slugs are dark gray or black; the larger slugs are yellow-gray or brown mottled with black and usually have 3 rows of black spots running the length of the body. Young slugs are off-white, thin, and around 1/2 inch long; young slugs darken and develop slowly.

Garden Springtail (Bourletiella hortensis): This springtail is black to dark purple with yellow spots, around 1/25 inch long, and has a soft, rounded body. They chew holes in leaves and make pits in the cotyledon leaves of a few vegetables.

Banded Greenhouse Thrips (Hercinothrips femoralis): Thrips are dark brown to black; the head, prothorax, and end of the abdomen are reddish-yellow and the forewings are dusty with white areas.

Bean Thrips (Caliothrips fasciatus): Nymphs are very slender and reddish-yellow. Adults are grayish-black with 2 white bars across the front wings and around 1/25 inch long. Nymphs and adults feed in colonies on the foliage and cause the foliage to become bleached, silvered, wilted, and covered with tiny black dots of excrement.

Flower Thrips (Frankliniella bispinosa): Adults are amber or brownish-yellow with an orange thorax and around 1/20 inch long; young thrips are lemon yellow. They only injure flowers; they can be seen inside the petals, usually near the base.

Onion Thrips (Thrips tabaci): Adults are pale yellow to dark brown with dusky gray wings and about 1/25 inch long. Nymphs are similar to adults, but are paler in color. This is probably the most widely distributed thrips in the world; it can attack almost every crop that is grown.

Tubulifera Thrips (Haplothrips clarisetis): Thrips are dark brown to jet black with silvery wings.

Western Flower Thrips (Frankliniella occidentalis): Thrips vary in color from lemon yellow to tan; they can cause blossom drop of several vegetables   including peas, melons, and tomatoes.

Threecornered Alfalfa Hopper (Spissistilus festinus): Adults are light green, wedge shaped, and about 1/4 inch in length. Nymphs are straw colored, wedge shaped, and wingless. Both adults and nymphs suck plant sap from stems and petioles.