EFFECT OF STAGE AND HEIGHT OF CUTTING ON THE DRY MATTER YIELD AND PERSISTENCE OF INTERMEDIATE WHEATGRASS, BROMEGRASS, AND REED CANARYGRASS

Abstract

The effects of harvesting at three heights of cutting and four stages of development on the dry matter yield and persistency of intermediate wheatgrass, Agropyron intermedium (Host.) Beauv., bromegrass, Bromus inermis Leyss., and reed canarygrass, Phalaris arundinacea L., were studied at two sites on irrigated land.The dry matter yield of all species decreased with increasing heights of cutting, and increased with advancing maturity at the time of taking the initial harvest. Highest yields were obtained from all species when cut at a height of 3.8 cm during the seed stage of development. However, this height of cutting resulted in the highest degree of winter injury and the most rapid stand deterioration. Bromegrass was less sensitive to variation in cutting height than intermediate wheatgrass or reed canarygrass. On well-drained, irrigated land, intermediate wheatgrass yielded significantly more forage than either bromegrass or reed canarygrass.The application of a regression analysis to the study of significant interactions among management factors and species within a single test proved to be a very useful statistical approach.