Influence of growth period on neps in cotton

The interactions between picking dates, locations, and varieties were studied to evaluate the effect of growth period on neps in ginned lint, yarn, and fabric. Five harvest intervals were selected, and the cotton yield increments between intervals were used to provide five levels of maturity. Neps in raw cotton were measured by the USDA-AMS web nep test and microscopic examination of card web, imperfections in the yarn ascertained by the Uster instrument, and neps in woven fabric counted by dyeing procedures. Results showed that growth period has a significant impact on the number of neps and other imperfections found in lint and manufactured yarns and fabrics. As a general rule, cotton grown early in the season will produce yarns and fabrics with a lower number of imperfections than cotton grown late in the season from the same field.