Optimizing late winter plantings of cool-season annual forages in the southern United States

Abstract

Cool-season annual grasses complement bermudagrass [Cynodon dactylon (L.) Pers.] pastureland production in the southern United States. These species can be planted in the fall or in late winter to provide supplemental forage strategically in the growing season. Late winter plantings can also provide emergency forage where perennial stands have been affected by drought. The optimum late winter planting date is not well established for these annual forages. This experiment sought to compare the forage production from three late-winter planting dates of four annual grasses. This experiment was conducted at the Arkansas State University farm in Jonesboro, AR, from 2021–2024. Winter wheat (Triticum aestivum L.), spring and winter oats (Avena sativa L.), and annual ryegrass (Lolium multiflorum Lam.) were no-till planted into a glyphosate-suppressed bermudagrass sod on one of three planting dates. Early planting dates were in late February, Mid planting dates were in mid-March, and Late planting dates were in late Match. Plots were harvested once in early May of each year. Winter wheat was the least productive forage across planting dates in all years. Spring oat was the most productive forage (approximately 4200 lbs acre⁻¹). The early and mid-planting dates produced similar amounts of forage at time of harvest. Late plantings were less productive (approximately 3000 lbs acre⁻¹). These results were consistent despite the variability in weather conditions across multiple seasons and establishment attempts. This experiment suggested that the optimal planting period for late winter-planted annual forages is between late February and mid-March in the southern United States.