Over the past five years (1983-1987), a series of studies were conducted to evaluate the effects of variety, planting date, harvest timing, and number of lint cleaners on final lint yield and grade. While slightly lower in yield (5%), smoothleaf varieties were significantly higher in grade for a given level of lint cleaning than hairy leaf varieties. Planting by May 6 produced higher yield and grade than planting on May 14-16. Yield and grade were higher for twice-over and once-over harvest compared to delayed harvest. After the boll is open, cumulative rainfall greater than two inches significantly reduced yield and lint quality.