Rotational graziers can save time and money by stockpiling forage. Stockpiling can extend the grazing season and let livestock do the harvesting, says Keith Johnson, Purdue University extension forage specialist.
"Anything we can do to allow our four-legged creatures to graze in a pasture beyond the traditional grazing season is a cost-effective approach," Johnson says. "By having the animals harvest the hay into December and, perhaps, January, producers can reduce the cost of delivering hay bales to them every day."
To stockpile forage, a grower should set aside about 25% of a pasture around mid-August. That portion should be left to grow while the remaining 75% is harvested mechanically or grazed.
"The forage that is best adapted for stockpiling in Indiana is tall fescue, a cool-season grass," Johnson says. "Tall fescue continues to accumulate yield even when temperatures are quite cool into October. It's also not uncommon for other cool-season grasses and legumes to be part of a stockpiling program, too."
Annuals planted after winter wheat grain harvest can be part of the rotational grazing system in the late summer and into the fall, as well, Johnson says. Typical annual forage choices include sorghum-sudangrass, sudangrass, pearl millet, spring oats and forage turnips.
Whatever grass-legume combination a producer chooses to stockpile, a healthy pasture is vital, Johnson says.
"It's not unusual in a grass-dominant stand to think about applying 30-50 lbs of nitrogen per acre to grow more forage for grazing," he says. "Of course, with the cost of nitrogen fertilizer these days producers have to be wise about the amount that should be applied, when it is applied and the nitrogen source that is used.
"The nitrogen source is critical because some types, like urea, can volatilize in dry conditions. In addition, if a producer has at least 30% legume in a stand, that legume probably is providing enough nitrogen to grow a productive grass crop, so nitrogen fertilizer might not be necessary at all."
To control perennial weeds, producers might apply herbicide in paddocks designated for forage stockpiling, Johnson says. However, herbicides used to reduce perennial broadleaf weeds also can kill the legumes a producer is trying to grow as part of a pasture mixture.
"They'll have to decide whether it's better to address the weed problems or spare the legumes," Johnson says.
Other points to remember when stockpiling forage include harvest timing and the dry matter needs of livestock.
Producers should not harvest mechanically about six weeks before a killing freeze, so the forage can grow back and accumulate needed reserves for spring regrowth, Johnson says.
"Something that works well is allowing a hay field to grow its last crop and then bringing in livestock for a post-dormancy grazing, instead of performing a post-dormancy harvest with equipment," he says.
How many days a paddock can be grazed depends on the amount of forage produced, the dry matter intake of each animal and number of animals grazing in the paddock.
"It's not unusual for a cow that's just weaned her calf to require a daily dry matter intake of 2.5% of her body weight," Johnson says. "So, for a 1,000-lb cow, that comes out to 25 lbs of dry matter forage per day."
For additional forage management tips, visit Purdue's Forage Information Web site at www.agry.purdue.edu/ext/forages/index.html.