Hardlock of cotton is a widespread problem in the southeastern United States. Symptoms do not appear until the boll opens and the fiber does not fluff out, remaining instead compact and somewhat within the boll. Although the quality of the fiber is not severely affected, yields are reduced because conventional cotton pickers cannot harvest the fiber in the hardlocked bolls. The etiology of the disease is still undetermined, however it is associated with high nitrogen, high temperature and humidity, high plant density, insect damage, and seed rot. This study showed that fungi, especially Fusarium sp., isolated from the vascular elements of the peduncle, were also associated with the disease and that the amount of cotton actually harvested could be increased with applications of benomyl even when symptoms of Fusarium wilt of cotton were not present.