Growth and Yield Comparisons of Cotton Planted in Conventional and Ultra‐Narrow Row Spacings

Cotton (Gossypium hirsutum L.) growers are faced with rising production costs and static or declining crop prices. One strategy with potential for reducing production costs entails growing cotton in ultra-narrow rows with elevated plant populations. A 2-yr field study was conducted in the Brazos Bottoms near College Station, TX to determine the differences in vegetative growth and yield parameters of cotton grown in ultra-narrow and conventionally spaced rows. Four row spacings of19, 38.1, 76.2, and 101.6 cm were planted with populations of 39.4 to 45.8, 18.2 to 20.7, 13.1 to 13.6, and 7.9 to 9.9 plants m -2 , respectively. At crop maturity, plant height and node counts were reduced in the cotton grown in the 19-cm row spacing. Canopy closure occurred more rapidly in the 19- and 38.1-cm row spacings than in the wider row spacings. In 1997, a relatively wet growing season, yields were not affected by the row-spacing treatments. In 1998, a dry growing season, yields in the 19- and 38.1-cm row spacings were greater than those in the wider row spacings. The 19-cm row spacing had 84.6% of the harvestable bolls at the first fruiting position and 76.1% of the bolls on Nodes 6 through 10, both percentages being significantly greater than those observed in the wider row spacings. Fiber length tended to be reduced in the 19-cm row spacing relative to the other row spacings. Ultra-narrow row cotton appears to be a viable option for producers to attempt to reduce costs while maintaining yields.