Dryland cropping system impact on forage accumulation, nutritive value, and rainfall use efficiency

Abstract

Forage cropping systems have greater precipitation use efficiency compared with cereal grains and oilseed cropping systems. However, information is limited to which forage species and forage rotation system increases productivity the most in the central Great Plains. The objective of this research was to identify the productivity and nutritive value of forage sorghum [FS, Sorghum bicolor (L.) Moench], winter triticale [WT, ×Triticosecale Wittm. ex A. Camus (Secale × Triticum)], and spring triticale (ST) crop rotations in the central Great Plains. The study was conducted from 2008 through 2011 at Garden City, Jetmore, and Tribune, KS. The experimental design was a randomized completed block with four crop rotation treatments: continuous FS–FS, continuous WT–WT, annual double-crop WT/FS, and 2-yr, double-crop WT/FS–ST rotations. The annualized forage accumulation from WT/FS–ST rotation at Garden City, Jetmore, and Tribune were 30, 53, and 62% greater than annualized yields from the WT–WT rotation, respectively. The annualized forage accumulation from double crop WT/FS rotation were 55 and 148% greater than annualized forage accumulation from WT–WT rotation at Garden City and Jetmore. Overall productivity of a rotation was in the order WT/FS > WT/FS–ST or FS–FS > WT–WT. Despite its greater productivity, it was difficult to implement field operations (planting and harvesting) in the WT/FS rotation due to insufficient time in the growing season and because, often, there was little to no soil water available at planting. We concluded the WT/FS–ST rotation was less intense and more easily adoptable than the WT/FS rotation and has sufficient diversity to utilize resources better than continuous FS–FS or WT–WT rotations.