Performance of short-lived perennial grasses grown with and without alfalfa at a semiarid location in southern Saskatchewan

Abstract

Tyically, crop rotations in the semiarid region of the Canadian prairies do not include perennial forages because forage termination produces negative effects on subsequent annual crops. Three short-lived perennial grass species, Dahurian wildrye grass (Elymus dahuricus Turcz. Ex Griseb), intermediate wheatgrass [Elytrigia intermedia (Host) Nevski] and slender wheatgrass (Elymus trachycaulus (Link) Gould ex Shinners), were compared for their forage productivity and persistence as short duration (3 yr) forage stands, either in a mixture with alfalfa (Medicago sativa L.) or in monoculture, in three trials at Swift Current, Saskatchewan. Intermediate wheatgrass produced 29 and 22% more forage and was more persistent than Dahurian wildrye or slender wheatgrass, respectively. In alfalfa mixtures, however, the grasses produced similar forage yield in two of three trials. Intermediate wheatgrass was more persistent in mixtures but yield compensation by alfalfa grown with Dahurian wildrye and slender wheatgrass produced similar total forage yield as these grass stands thinned during the third year of each trial. Intermediate wheatgrass and alfalfa mixtures could be utilized for short rotation forage stands in high-input crop sequences where stand termination is achieved with herbicides. Dahurian wildrye and alfalfa mixture has the best potential for short-rotation forages in organic crop systems of this region because it would require less tillage to terminate the stand. Key words: Crop rotation, forage yield