Interference Periods of Common Cocklebur (<i>Xanthium strumarium</i>) with Cotton (<i>Gossypium hirsutum</i>)

Abstract

Cotton ( Gossypium hirsutum L.) was grown in the presence of common cocklebur ( Xanthium strumarium L. # XANST) on a Lucedale fine sandy loam. Cotton was maintained weed free or allowed to compete with common cocklebur for 0, 3, 5, 7, 9, or 11 weeks after planting. Mathematical predictions of seed cotton yield were optimum when maintained free from common cocklebur interference for 8 weeks or more after cotton emergence in 1981 and 1982, and 10 weeks or more in 1980. Common cocklebur adversely affected yield when allowed to compete longer than 4 weeks in 1981 and 1982, and 2 weeks in 1980.