Yield variability and water use in wide-spaced furrow irrigation

Abstract Characteristics of crop yield and water use in wide-spaced furrow irrigation (W) were compared to every furrow irrigation (E). The study was conducted at Goodwell, Oklahoma on a clay loam soil with grain sorghum ( Sorghum bicolor (L.) Moench). E furrows were 1.42 m apart and W applied water to alternate furrows, making a 2.84 m spacing. W treatments caused no greater yield variation down the furrow than the E treatment, although about 1 2 the water was applied to the W plots as for E. In the W treatments not all furrows were irrigated at any one time and, on occasion, the dry furrows were noted to crack. Subsequent irrigation to cracked dry furrows showed significantly greater penetration of water into the profile than the E treatments. Soil water tended to be depleted to greater degree in the W treatments than the E treatment over the growing season, but seasonal evapotranspiration was lesser in the W plots.