Cotton Bollworm is closely related to Tomato Fruitworm and Corn Earworm. Adult moths are usually light yellowish-olive with a single dark spot near the center of each forewing. Each forewing has 3 slanted dark olive or brown bands. Their hind wings are white with white borders. The eggs of this pest are spherical with a flattened base, about 0.6 mm in diameter, and white or cream color. The eggs are laid on upper and lower sides of leaves. They develop a reddish-brown band just prior to hatching.
The larvae are creamy-white with a black head. Color varies from greenish-yellow and reddish-brown or even black with paler stripes running lengthwise on the body. Pupae are shiny and reddish-brown at first, then become dark brown before the adult emerges.
The larvae take advantage of fruit or bolls and complete their larval development inside them. They enter through the stem end and they create a watery internal cavity that they fill with molted skins and feces. In tomatoes, they cause the fruit to ripen prematurely. In cotton, they leave gouges on the surface of the boll where rot organisms enter and spoil the cotton crop. Later in the season, they will enter ripe fruit/bolls and cause them to be inedible/unusable.
Organic Control Options:
- Applications of Bacillus thuringiensis kurstaki.
- Release of Trichogramma pretiosum when adult moths are spotted.
For control products and more information please see our Caterpillars and Moths Control page.
Photo courtesy of Clemson University Department of Entomology, Soils & Plant Sciences, Cooperative Extension Service.