Experiments were conducted at Clemson University's Pee Dee Research and Education Centre in Florence, SC, in 1989 and 1990 to compare responses of NF and DN flue-cured tobacco genotypes to topping treatments; and to determine the effects of removal of lower leaves on NF tobacco genotypes on yield and quality of cured leaf. Experiments compared topping heights [76, 102 (recommended), or 127 cm; "raised swath" (lower six leaves removed); no topping] for two NF genotypes and two normal cultivars. In both years, yield, crop value, grade index and total alkaloids were significantly higher for NF genotypes than for DN cultivars. Yield and crop value tended to increase with topping height. However, the difference between topping at 102 and 127 cm was not significant in both growing seasons for NF genotypes. Topping at 102 cm, generally produced higher yield and crop value than the RS treatment in both seasons (except NC 27 NF in 1990), both treatments had similar harvestable leaves for NF genotypes. Raised swath treatment had higher price and grade indices in 1989 than topping at 102 cm, but these treatments produced cured leaf of similar price and grade indices in 1990. Topping at 102 cm, compared to RS treatment, produced cured leaf with higher total alkaloids in both seasons. Reducing sugar concentration was significantly higher for DN cultivars than NF prototypes in 1989, but was similar between NF genotypes and Coker 319 in 1990. Leaf measurements are also discussed.