How to Manage Pests

Tomato russet mite—Aculops lycopersici

Tomato russet mites are so tiny they cannot be seen without a hand lens. You will see the bronzing they cause on leaves first. Russet mites are conical in shape and yellowish, tan, or pink.

Identification

Tomato russet mites are very small — only about 1/5 mm long, so you need at least a 14X lens to see them. Damage would first be present mid- to late summer when plants are half-grown or longer. Damage typically begins on stems and spreads upward. Fruit are usually not attached, but defoliation may expose them to sunburn. If you see damaged leaves, check them for mites. Also check some green leaves just above damaged ones; the mites may move up the plant above the most obvious damage.

Don't confuse russet mites with spider mites, which are rounder and larger, usually have two spots, and often produce webbing. Predatory mites are clear and move rapidly.

Damage

Leaves and stems damaged by mites develop a greasy appearance, then dry out and turn bronze. Damage starts at the base of the plant and moves upward. In hot weather when mite populations explode, plants may be defoliated.

Solutions

Both sulfur dust and wettable sulfur are effective for russet mite control. Do not grow tomatoes near petunias or any solanaceous plants, such as potato, as they are other hosts of the russet mite.

Russet mites

Russet mite damage