Sainfoin production in western Canada: A review of agronomic potential and environmental benefits

Abstract

AbstractSainfoin (Onobrychis viciifolia) is a forage legume of renewed interest in western Canada, with equally weighted advantages and disadvantages. In agronomic attributes, sainfoin is, at best, equal in yield, crude protein content and persistence to alfalfa (Medicago sativa). Sainfoin is equally or more palatable than alfalfa to ruminants, with comparable levels of animal productivity per unit forage consumed. The advantages it has compared to alfalfa include the following: (a) mitigation of frothy bloat; (b) reduced ammonia emissions (more faecal nitrogen (N) and less urinary N); (c) equal or better N retention by ruminants; and (d) anthelmintic protection from intestinal parasites. These advantages may be attributed to the presence of condensed tannins (CT), in legumes such as sainfoin. Emphasis on agronomic characteristics in breeding programmes appears to have led to the inadvertent reduction in the efficacy of CT characteristics. Persistence of sainfoin appears to be dependent on minimal pressure from competing plants, harvest or grazing, and good growth conditions from mid‐summer into fall, allowing for adequate root reserves for survival. It is possible that judicious use of glyphosate in late season might lessen competition in that critical period as sainfoin is more glyphosate‐tolerant than alfalfa. Otherwise, sainfoin may be best considered a short‐lived forage and best adapted for early season harvest or grazing to eliminate the risk of bloat.