The Effect of the Spacing of Cotton Upon the form and Height of the Plant

Abstract

This paper reports results of cotton growth on Mississippi River Bottom soil at the Louisiana Experiment Station, Baton Rouge, Louisiana. In 1924, with total rainfall of 7.15 inches during June, July and August, Salisbury cotton averaged 1588 pounds seed cotton per acre. The same variety on similar soil in 1925, with a normal rainfall amounting to 14.48 inches during June, July and August, produced an exceedingly rank weed growth with abundant blooming but practically complete shedding of small bolls and no crop was picked. Spacing tests were conducted in 1926 with Lone Star No. 65 cotton on similar soil, planted June 25 and records completed by September 25. Rainfall during June, July and August amounted to 25.51 inches and a severe tropical storm occurred on August 25, when over 10 inches of rain fell. The widest spacing, single plants 24 inches apart, produced invariably the lowest and broadest growth with thickened bases to the stalks, heavy vegetative branches and delayed setting of bolls. The unthinned cotton was extremely slender and whip-like with no vegetative branches and very few bolls. In all spacings varying from single stalks at 8 inches to 3 to 5 stalks per hill, there developed a practically full stand of from 16,000 to 18,000 stalks per acre having “normal growth” and fruiting. These stalks were, as a rule, moderately slender, with few if any vegetative branches and reaching a rather uniform height of 38 to 42 inches at three months of age. Hill spacing with 3 to 5 stalks at 12 to 15 inches apart appeared to give the most practicable and desirable spacing.