Scales appear as clusters of crusty, waxy, or smooth bumps on leaves, branches, and the bark of trees and shrubs. There are numerous types varying in size, color, and shape. They spend most of their lives immobile, sucking nutrients out of their plant victims. Black sooty mold fungus may cover parts of the plant; heavily infested twigs and branches may die. Scales have protective coatings that help prevent sprays from affecting them; young crawlers are most susceptible to sprays.

Commercial product: Insecticidal soap spray (such as Safer), or horticultural oil
Home remedy: Homemade soap spray (add ½ teaspoon mild dish soap and 1 teaspoon cooking oil to a 1-quart sprayer filled with water)

Gentle pest controls