Larvae are up to 18mm long, thickset, mottled grey and brown with irregular yellow-orange spots in rows along the back. Moths are 11mm long and are off-white with a green or brown stripe on the forewing. Eggs are initially blue-green and difficult to find.
Damage: Most severe damage occurs when the larvae feed inside the green boll resulting in the loss of that boll section. Feeding sites can also allow the entry of boll-rotting fungi. Larvae can attack squares and young bolls resulting in shedding. Initial symptoms can be tunnelling into the growing point, destroying it.