Comparing annual and perennial forage systems: Effects on yield, quality, steer performance, emissions, and profitability

ABSTRACT Objective This study compared annual and perennial forage systems for yield, quality, grazing animal perfor-mance, enteric emissions, and economic viability. Materials and Methods Four forage systems were evaluated, consisting of 2 annual systems: (1) BAR-PEA-BRAS: CDC Austenson barley ( Hordeum vulgare L.) + 4010 pea ( Pisum sativum L.) + Winfred forage brassica ( Brassica oleracea L. × Brassica rapa L.) + Gorilla forage brassica ( Brassica napus L.); (2) FALLRYE-CLOV: AC Hazlet fall rye ( Secale cereale L.) + Frosty berseem clover ( Trifolium alexandrinum L.); and 2 perennial systems: (3) HYBROME-ALF: AC Success hybrid bromegrass ( Bro-mus riparius Rehm. × Bromus inermis Leyss.) + PS3006 alfalfa ( Medicago sativa L.); (4) MBROME-SAIN: AC Armada meadow bromegrass ( Bromus riparius Rehm.) + AAC Mountainview sainfoin ( Onobrychis viciifolia Scop.). In the 5-yr study (2019–2023), crossbred Bos taurus steers (n = 156; initial BW = 388 ± 9 kg) were randomly al-located to 1 of 4 replicated (n = 3) forage systems for an average grazing period of 54 d. Results and Discussion The BAR-PEA-BRAS and HYBROME-ALF systems had the greatest DM yield, whereas MBROME-SAIN and FALLRYE-CLOV yields were lower but not different from each other. Annual for-ages had greater TDN and digestibility of CP and NDF but lower NDF content than perennial forages. Steers grazing FALLRYE-CLOV had the greatest DMI compared with other systems. Total beef production was greatest for the HYBROME-ALF system (124 kg/ha). Steers grazing annual forages had lower enteric CH 4 (g/kg DMI and g/ kg ADG) relative to steers grazing perennial forages. The HYBROME-ALF system had greatest revenue and profit-ability of the 3 valuation methods. Implications and Applications The hybrid brome-grass and alfalfa mixture showed the highest forage pro-ductivity and profitability, making this system a valuable choice for beef cattle grazing programs in the Canadian and Pacific Northwest beef industries.