Effective weed control has always been a problem in cotton production for two reasons 1) a limited arsenal against broadleaf weeds and 2) weeds that emerge following planting. The introduction of Roundup Ready technology into cotton varieties and the benefit that this technology gives to weed control in cotton production has spurred a rapid acceptance of new transgenic varieties by cotton producers. Several new Roundup Ready (RR) and Bollgard/Roundup Ready (B/RR) varieties have recently been released by Deltapine Seed and other seed companies. To select and manage a specific variety from an expanding list of choices, the grower must understand the growth and fruiting characteristics of the variety. Cotton plant mapping is a tool used to quickly and effectively characterize the growth and fruiting parameters of cotton varieties across differing environments and management practices. To effectively characterize the growth and fruiting characteristics of the Deltapine Seed Roundup Ready cotton varieties, four replicated on-farm trials and five Roundup Ready system strip trials were set up across southeast Texas in 1998. Data collected in 1998 indicate that DP 436 RR and DP 425 RR are shorter maturity varieties, which is consistent with their recurrent parents of Deltapine 50 and Deltapine 51 respectively. DP 458 B/RR and DP 5415 RR appear to be fuller season varieties with a shorter plant structure. Given their growth characteristic, they had the highest and most consistent yield profile across East Texas in 1998. DP 655 B/RR and DP 5690 RR are fuller season varieties with a taller plant structure.