Tests were conducted during 1999 (Macon Ridge Station and Madison Parish) and 2000 (Macon Ridge Station) to determine the effects of Phomopsis boll dangle (PBD) (vascular cavitation) on cotton development in four cotton varieties. Epidemics were monitored in NuCOTN 33 ^B and Deltapine 90 ^RR in 1999 and in Phytogen 355 and Acala Maxxa in 2000. Fifty plant pairs were tagged during mid-July and monitored for PBD severity during the season. A pair consisted of a PBD affected plant and a non-affected plant. Each plant was monitored for the number of harvestable bolls (approximately 24 days or older) and the number of mummified bolls was recorded on PBD affected plants. At harvest each plant was hand picked and seedcotton was segregated by the amount taken from 1 ^st , 2 ^nd , >2 ^nd , and vegetative sites. In 1999, PBD affected plants produced more harvestable bolls and seedcotton than non-affected plants. In 2000, harvestable bolls did not differ among affected and non-affected plants. Seedcotton amounts were greater for affected plants of Phytogen 355, but did not differ among affected and non-affected plants of Acala Maxxa. The majority (54% to 72%) of affected bolls were located on first position sites for all varieties evaluated. These results suggest that PBD is not a problem in the varieties evaluated in these studies.