Cotton is planted annually by seed in furrows; the plants are thinned and weeded during the spring growing season. Diseases and insect pests are numerous; of these the most destructive has been the boll weevil, which has caused enormous losses. Genetically altered strains of cotton are being developed that can resist infestation by some insects and damage by application of herbicides.
Mechanical harvesting is preceded by a chemical-defoliant spray to remove the leaves, leaving only the cotton bolls. In the ginhouse the cotton is separated from the seeds by a cotton gin and then baled. The usual plantation bale, weighing 500 lb (227 kg), is covered with jute and bound with iron hoops. The U.S. Dept of Agriculture has established standards for grades of cotton. The manufacture of cotton cloth involves many processes—carding, combing, and spinning—which transform raw fiber into yarn or thread strong enough for weaving.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.