The species Brevicoryne brassicae is commonly known as the cabbage aphid and is a common pest to many Brassica and cole crops. Large infestations can result in the stunting or death of the plant; however, the contamination of the harvested crop is the most problematic issue to handle. A key distinguishing feature of this species is its habit to form colonies that appear white and waxy. The species is also known to transmit the Turnip Mosaic Virus (TMV), a disease that causes necrotic rings in crucifers after they have been in storage.
The adult aphid can be either winged or wingless, measure approximately 2 mm in length and are a greenish-gray. The winged aphids have a white waxy coat. The wingless species are black.
Check each field at least twice a week. Sample upwind field borders and edges next to other crucifers first; since this is where aphids commonly appear. However, when conducting field samples use a zigzag patter, to get a thorough-representative sample of the pest. Remember to check all quadrants of the field because aphid populations are often clumped.