A two-part study was conducted to determine if leaf hairiness can explain varietal tolerance to 2,4-D. Materials used in the study were Paymaster 145 (a commercial variety with more leaf hairs than most varieties), Texas Marker-1 isolines pilose (H(2)), and Smooth leaf (Sm(2)). A single application of 0.5 lb/A concentration of 2,4-D was drifted across the three entries. Visual ratings showed leaf hairiness to be beneficial in reducing the damage caused by 2,4-D. Percent reduction in lint yields showed Paymaster to be better than pilose in tolerance to 2,4-D, indicating an additional genetic mechanism in Paymaster 145. The direct application of 0.001, 0.005 and 0.01 concentration of 2,4-D applied on 35 and 52 DAP showed no cultivar by date interactions. Visual ratings were better at 0.001 concentration for the pilose entries. Paymaster 145 was significantly better at 0.005 and 0.01 than was TM-1 pilose, which was better than TM-1 Smooth leaf. Percent reduction in lint yield for the pilose entries were significantly lower than those for TM-1 Smooth leaf at 0.001 and 0.005. At the 0.01 concentration, Paymaster 145 was significantly better than TM-1 pilose which was better than TM-1 Smooth leaf. Again, the results indicate and advantage to leaf hairiness, but also, showing the presence of an additional genetic mechanism in Paymaster 145.