Problem Identifier Unit Screen//v.w/ RR Template

Problem Identifier Unit Screen//v.w/ RR Template Aphids

Broccoli, brussels sprouts, cabbage, Chinese cabbage, cauliflower, collards, kale, kohlrabi

Problem
Some leaves are yellowed and cupped downward. Tiny (1/8 inch), pale green or gray soft-bodied insects cluster under leaves, on stems, and on heads. There may be a shiny, sticky substance coating the leaves. Ants may be present.

Analysis
Aphids do little damage in small numbers. However, they are extremely prolific and populations can rapidly build up to damaging numbers during the growing season. Damage occurs when the aphid sucks the juices from the plant. The aphid is unable to digest fully all the sugar in the plant sap and excretes the excess in a fluid called honeydew. The honeydew often drops onto the leaves below. Ants feed on the sticky substance, and are often present where there is an aphid infestation. The most common aphid attacking the cabbage family is the cabbage aphid (Brevicoryne brassicae). The cabbage aphid spends the winter as eggs on plant debris in the garden. In the South, they are active the year around. For more information about aphids, see Aphids.

Solution
Treat with an insecticide containing malathion or pyrethrins, or an insecticidal soap as soon as the insects appear. Repeat at intervals of 1 week if the plant is reinfected. Clean all plant debris from the garden after harvest to reduce the number of overwintering eggs.

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