Forage mixtures containing legume out-yield monocultures, fix atmospheric N, and have lower C footprints. However, evidence-based information on creating forage mixtures by direct seeding legumes into existing pastures is limited and bloat-free legumes non-existent. Traditionally, pastures requiring improvement in western Canada were fully replaced by breaking up the old stand and re-seeding. With new and improved forage cultivars, better seeding equipment, and increased knowledge about pasture management, there is a growing interest among producers in rejuvenating pastures instead of replacing them. Pasture rejuvenation refers to the improvement in biomass productivity and/or nutritional quality of existing pasture without removing the existing vegetation. This can be done through fertilizer application, which is generally expensive and causes negative environmental impacts. Amelioration of compacted pastureland via mechanical aeration is short-lived and can lead to weed problems. As an alternative, direct seeding of productive, nutritive and bloat-free legume species into existing pasture is an attractive option for pasture rejuvenation. For high performance grazing systems, identification of suitable bloat-free legumes and methods for direct seeding into old grass and legume stands will be essential strategies. This review includes information on the benefits of mixed pastures and seeks possible methods of introducing bloat-free forage legumes into existing pastures in western Canada for rapid improvement in productivity and quality while positively influencing animal, soil and environmental health.

Sod‐seeding of depleted pastures with non‐bloating legumes can be a low‐cost pasture rejuvenation strategy for ranchers in the North American prairies. A study was conducted to determine if sainfoin (Onobrychis vicifolia subsp. vicifolia) or cicer milkvetch (CMV) (Astragalus cicer L.) populations or cultivars (hereinafter populations) can be used to rejuvenate alfalfa (Medicago sativa L.) or grass pastures. The study included sainfoin populations with increased fitness to grow with alfalfa and CMV cultivars that were selected for early emergence and rapid seedling growth. These populations were seeded using three seeding methods: traditional re‐seeding, drilling seed with Great Plains drill, or Pan drill, using split‐plot randomization at three locations in Alberta in 2015 or 2016. Lethbridge had pre‐existing alfalfa while Ponoka and Red Deer were predominantly grass pastures. The sod‐seeded rejuvenation, as indicated by percentage dry matter (DM) contributed by newly planted species succeeded at Lethbridge (≥15), failed at Ponoka (∼1), and partially succeeded at Red Deer (≥9). Successful establishment of new plants did not increase the total forage mass of the rejuvenated pasture. Sainfoin populations established better and contributed greater forage mass compared to CMV cultivars when sod‐seeded on alfalfa pasture, but the improvement was not consistent on grass pasture. Forage nutritive values were not different among populations within species, but pasture seeded with CMV cultivars had greater crude protein than unseeded plots. Sod‐seeded grass–legume pasture had greater crude protein than unseeded plots at Red Deer. Sod‐seeding alfalfa pasture with sainfoin populations can be an efficient pasture rejuvenation strategy.