THE POTENTIAL VALUE OF Hedysarum alpinum var. americanum AS A FORAGE LEGUME FOR THE NORTHERN CANADIAN PRAIRIES

Abstract

Hedysarum alpinum L. var. americanum Michx. (American hedysarum) is indigenous to parts of Saskatchewan. Plants grown from seeds collected at five locations in central Saskatchewan were transplanted into a nursery at Saskatoon, Saskatchewan and a study of the nutritive value of individual plants was undertaken to determine the potential value of American hedysarum as a forage legume for the northern Canadian prairies. Leaves and stems (analyzed separately) showed marked differences in chemical composition. However, they did not differ in the in vitro organic matter digestibility (OMD). American hedysarum plants had a much higher tannin content than alfalfa or birdsfoot trefoil plants grown at the same location. This may account for the relatively low OMD of this species. The protein and fiber fractions (of H. alpinum) compared favorably with those of alfalfa. Improvement by breeding for reduced tannin content would be necessary before American hedysarum would be acceptable as a forage crop.Key words: Hedysarum alpinum L. var. americanum Michx., American hedysarum, forage, tannin, in vitro digestibility, early growth