Three experimental harvesting and storage treatments were applied to seed cotton in the Yazoo-Mississippi Delta to determine their effectiveness in preventing the development of aflatoxins during the period between harvesting and ginning. The experiments were conducted using full-scale production and ginning equipment. The experimental harvesting and storage treatments were (1) to harvest wet with dew and store without drying, (2) to harvest wet with dew and gin-dry before storage, and (3) to harvest after the dew had evaporated and store without drying. The storage period for all treatments was 7 days. Each treatment was replicated five times in each of two successive crop years. Development of aflatoxins in cottonseeds during seed-cotton storage may be minimized by ginning the picked-wet cotton by the end of the third day after harvesting and by ginning the field-dried cotton by the end of the fourth clay. Although the gin-drying treatment was successful in controlling aflatoxin production in stored cotton, it was considered impractical as a cotton-production process.