Sorghum–sudangrass (Sorghum bicolor × S. sudanense (Piper) Stapf.) and pearl millet (Pennisetum glaucum (L.) R. Br.) provide adequate nutritive value for growing beef cattle; however, unlike pearl millet, sorghum–sudangrass produces hydrocyanic acid (which is toxic to livestock) when frosted. Forage yield, nutritive value, and weight gain of growing cattle grazing sorghum–sudangrass and pearl millet were compared during the frost-prone autumns of 2013 and 2014, at New Mexico State University’s Rex E. Kirksey Agricultural Science Center in Tucumcari, NM USA, in randomized complete block designs each year with two replicates. No differences existed between pearl millet and sorghum–sudangrass forage yield, although there was a year–forage interaction for fiber-based nutritive value components because of maturity differences across years between the forages when freeze-killed. Pearl millet allowed for extending grazing of available forage for an additional 14 and 24 d in 2013 and 2014, respectively, compared to sorghum–sudangrass during the frost-prone autumn periods. During that period, when sorghum forages produce potentially toxic levels of hydrocyanic acid, animals grazing pearl millet accumulated an additional average of 94.9 kg live-weight gain ha−1 (p < 0.001). These factors afford producers an opportunity to increase returns on the similar investments of establishing and managing warm-season annual forage crops each year, and allow more time to stockpile cool-season perennial and annual forages for winter and early spring grazing, or to reduce hay feeding.

Forage-based beef production is one of the most productive agricultural systems, especially in semiarid, subtropical environments, yet it is temporally variable due to climatic factors. Dormant native perennial warm-season grasses are available for grazing from autumn through spring; however, their protein concentration is inadequate to support growing cattle. Winter cereal forages, such as triticale [×Triticosecale Wittm. ex A. Camus (Secale × Triticum)], can fill fall through spring forage gaps with sufficient protein concentration. Triticale productivity was evaluated, and beef stocker performance on triticale was compared with supplemented native grassland for late winter pasture in each of three years at New Mexico State University’s Rex E. Kirksey Agricultural Science Center in Tucumcari, NM USA. Study results indicated that triticale pasture forage mass varied over the three years due to precipitation and different triticale planting dates each year, influencing the length of grazing period. Triticale provided late winter average daily gain approximately twice that of cattle grazing dormant native grass with protein supplementation (0.70 vs. 0.36 kg hd−1 d−1, p < 0.0001). Therefore, triticale can be utilized to provide adequate growth of young calves without the added costs of supplementation.

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