Varying in size, shape, and color, the many species of these aphid cousins look like bumps on bark, leaves, and fruit. All are equipped with an insecticide-resistant coat, a leathery or waxy material in the case of soft scales, a sturdier covering for armored scales. Young scales (called crawlers) move around the plant, but they settle down and become immobile as they mature.
Target: All plants.
Damage: The plant looks unsightly: it loses vigor and wilts, or new growth is distorted. Branches and even whole plants may die. Honeydew excreted by soft scales attracts ants and fosters the growth of sooty mold.
Life cycle: Some scales lay eggs, often under a female’s protective covering; other types bear live young. Armored scales usually have several generations a year, soft scales only one.
Notes: Scrub scales off with a plastic scouring pad. Pesticides are most effective on crawler stage. Control ants which protect scales from natural enemies.