Review: Cool-season annual grasses or grass–clover management options for extending the fall–winter–early spring grazing season for beef cattle
2018
Mullenix, M.K. | Rouquette, F.M.
Cool-season annual forages may supply seasonal forage for grazing and reduce needs for stored forages and concentrate supplements for beef cattle producers in the southeastern United States. Opportunity exists to use small grains that vary in their individual growth distribution to extend grazing during the fall–winter–early spring seasons. Small grains adapted to the region include cereal rye (Secale cereale L.), wheat (Triticum aestivum L.), oats (Avena sativa L.), and triticale (Triticosecale Wittm.). These species have a bimodal forage DM production trait during the autumn and early winter months and can be grown in monocultures or mixtures. Fall forage production potential of these species has been primarily dependent on planting method, seeding date, soil fertility or fertilization, and variety selection. Small grain varieties may also be grown in combination with annual ryegrass (Lolium multiflorum Lam.), clovers, or both to extend the seasons of grazing for fall or winter-calving cows or stockers. Annual ryegrass and legumes in the Southeast include cold-tolerant and rust-resistant diploid and tetraploid varieties of ryegrass, and adapted true clover (Trifolium sp.) varieties. Autumn-planted ryegrass or clovers including crimson (Trifolium incarnatum L.), arrowleaf (Trifolium vesiculosum Savi), ball (Trifolium nigrescens Viv.), and red clover (Trifolium pratense L.) provide minimal to nonexistent forage mass for grazing during the fall. Naturally reseeding ryegrass or clovers may provide earlier forage mass compared with small grains; however, DM is usually not adequate for stocking until late-January to mid-February, and it extends through May. Tetraploid varieties of ryegrass, when seeded into a prepared seedbed, can provide adequate forage mass for fall grazing similar to small grains. Earliness of forage mass for stocking among clovers ranges from crimson (earliest) to arrowleaf and ball (mid to late) to white and red (late to early summer). These cool-season forage systems provide suckling calf ADG that may approach or exceed 1.5 kg/d and stocker cattle ADG of more than 1 kg/d. Management strategies for sustainable cow-calf production include the strategic use of cool-season forages, assessment of fertilization demands and timing, and assessment of stocking rate to optimize forage utilization and desired animal performance.
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