Matching production of winter forage annuals with livestock needs can be a challenging, but research and farm demonstrations by the University of Arkansas System Division of Agriculture can help in decision making.
“Forage turnip and rape must be planted early for fall grazing,” said John Jennings, professor-forages for the University of Arkansas System Division of Agriculture. “Brassicas planted in late August to early September can produce grazeable forage by late October.”
Tillage is required for good establishment. Light disking may be adequate. Clean tilled seedbeds are best. Brassicas can be grazed from October through December. A combination planting of forage brassica and ryegrass has proven to be an effective practice. The brassica produces forage for fall grazing and the ryegrass produces forage for spring grazing. Forage brassica varieties are much more productive than “garden-type” varieties.
Small grains, ryegrass
Jennings said that small grains and ryegrass intended for grazing by Nov. 1-15 must be planted before Sept. 15. Planting on a tilled seedbed or no-tilled into harvested crop fields is required for this to work. Apply 50 pounds per acre of nitrogen after the stand comes up to ensure growth. Apply phosphorous and potassium according to a soil test.
“However, if no soil test is available, be sure to apply at least 50 pounds each of potassium and phosphorous,” Jennings said. Apply 50 pounds more nitrogen in February for sustained growth into spring.
“Due to the tillage requirement, this option will not fit every case or every field,” he said. “
However, selecting specific fields for this early planting option may fill a void until other forage is available.”
For grazing by Dec. 1-15
Winter annuals intended for grazing in early December can be interseeded into warm-season grass sod or planted in crop fields from Sept. 15 to Oct. 1. The grass sod should be suppressed with a low rate of glyphosate herbicide or with moderate disking when planting this early to prevent competition with the small grain seedlings. Planting can be done with a no-till drill or by disking followed by broadcast of seed and dragging with a harrow. Apply 50 pounds per acre of nitrogen after the stand comes up to ensure growth. Apply phosphorous and potassium according to soil test. If no soil test is available, be sure to apply at least 50 pounds each of phosphorous and potassium. Apply 50 pounds more nitrogen in February for sustained growth into spring.
For grazing February to early March
Planting annuals after mid October into November will allow good establishment, but forage production will be delayed until February or early March. Fertilizer application can be delayed until February since growth potential is limited during mid winter.
How much to plant
Unsure how much to plant?
“Research has shown that a good measure for determining planting acreage is one-tenth an acre pre cow per day of the week to be grazed through the winter,” Jennings said. “Or example, if cows will be limit grazed three days per week then plant three-tenths of an acre per cow.”
More grazing time requires more acreage.
“Dr. Paul Beck's work has shown that cows limit grazed on winter annuals two days per week and fed hay the remaining time perform quite well,” he said. In that study, the "grazing day" was an eight-hour day and not a 24-hour period. As forage growth increases during the early spring, cows can be allowed to graze more frequently.
Beck is a professor in animal sciences based at the Southwest Research and Extension Center in Hope.
“This is an effective way to match the increased nutrient requirements of spring calving cowherds and to supplement low quality hay,” Jennings said.
Source: University of Arkansas Extension