Make most of available forage
Driving along rural highways in Iowa, the signs are obvious; the amount of pasture acres has decreased significantly over the last 10 years. The Iowa Beef Center has identified lack of available land as the biggest obstacle in expanding the state’s cattle herd.
According to the USDA Census of Agriculture, almost 20% of Iowa pasture acres were converted to cropland from 2002 to 2007. So, it’s even more important to make the best use of available pasture. Here’s how some Iowa cattle producers are using available acres in innovative ways to extend the grazing season.
• Winter stockpiling in fescue country. For Jim Werner, who has a seedstock and cow-calf operation in Ringgold County in southwest Iowa, rotational grazing has been paramount to making the most of available forage, which is mostly fescue in his operation.
“We have a lot of fescue that deserves a lot of the cussing it gets, but if I could take one grass, I’d take fescue,” he says.
Rotational grazing helps manage fescue by keeping it in a vegetative state, preventing toxicity issues. The practice also ensures cattle get off grass quick enough to allow regrowth. “The quicker you can remove the forage and let the cattle off to allow for regrowth, the better the roots are going to be,” he adds.
• Pasture acres have declined; it’s crucial to make the most of available forage.
• Rotational grazing and split-season calving help use forage more efficiently.
• Grazing cover crops and cornstalks, and stockpiling pasture extend grazing.
Werner’s 500 cow-calf pairs are divided into 250 spring-calving and 250 fall-calving cows, which also helps make the best use of forage. Fall calving avoids breeding in late spring and summer, when heat and fescue toxicity are at their worst. For his spring herd, Werner says it’s common to have 10% open cows, while about 5% of fall-calving cows come up open.
Fescue works well for stockpiling for winter grazing, when it goes dormant. “In summer, the roots are going to be proportionate to the grass above it,” Werner says. “In winter, you can graze down that same plant, and the roots are still there.”
Stockpiled fescue usually has around 12% protein — adequate to meet the nutrient requirements of a dry cow. However, in winter, nutrient requirements double for lactating cows, which are sustaining calves in addition to themselves. Werner says it’s important to supplement feed at this time. These cows usually drop to condition scores of 4 or 5 over winter. By summer, they reach 7 or 8, thanks to the flush of fescue in spring. “Fall-calving cows are a little easier to run in the summer, but they cost a little more in the winter,” he says. “Nothing is easier to keep in summer than a fall calving cow.”
• Grazing winter annuals. Three counties north in Dallas County, where Justin Rowe rotationally grazes, bromegrass is the prominent forage. Rowe usually grazes paddocks for a maximum of five days, leaving enough residual for regrowth until the next grazing. After leaving a paddock, he tries to wait 30 to 45 days before going back to it. However, recent dry years have required more rest.
“If I’ve been off a paddock for three weeks and it hasn’t grown much, I might slow down my rotation and give it another week or two to green up a little.”
Rowe also stockpiles pasture, and usually has enough acres to graze until mid-December. Being in central Iowa gives several additional winter grazing tools. After his pastures run out, he strip-grazes cornstalks and cover crops seeded into the acres he cuts for silage.
“It’s kind of a companion for silage. It puts more biomass on the ground where we’re taking it off the ground,” he says. It also gives cover crops a longer window for growth. “The earlier you get the cover crops planted, the better chance they have of getting established.”
These crops include a balanced mix of cereal rye, turnips, radishes, cowpeas and oats. The cows always go to rye first, then on to the turnips and the radishes, Rowe says. “They’ll chase those turnips and radishes into the ground. If they can pull them out they will.”
Brassicas like turnips and radishes are high in protein and energy, but low in fiber. This is where rye grain and oats come in. Rye is also hardy, and will sometimes green up for spring grazing, while radishes, turnips and oats winterkill.
“I try to use cover crops that will complement each other. So cattle have a little bit in each bite,” he says. “I like to have as many choices available as I can for feed.”
• Integrating cattle with crops. Although much of Hardin County is cropland, Dave Petty, who raises corn, soybeans and cattle near Eldora in north-central Iowa has the advantage of integrating cattle with crops.
“It’s a little different topography than some of the other grazing opportunities,” he says. “I’m able to use a lot more conservation in my operation because of cows.”
In addition to grazing cornstalks, Petty also uses the grass waterways in his cornfields for stockpiled winter grazing and hay. Petty’s pastures consist of brome, and he usually frost-seeds red clover in spring to add feed value and produce his own nitrogen.
“A rule of thumb is if you can get a third of your stand to be legume, you’ll get 40 pounds of nitrogen produced per acre,” he says. “A lot of farmers apply 40 to 60 pounds of nitrogen per acre to fertilize pasture. With red clover, all of a sudden you’re growing the nitrogen you need.”
Petty also spreads phosphorus and potassium in fall. When it rains, it takes the fertilizer down to the root system. Unlike nitrogen, phosphorus and potassium aren’t as mobile. By delivering phosphorus and potassium directly to the root system, Petty’s bromegrass usually comes up two weeks earlier in spring.
Petty rotationally grazes his pasture, giving it more rest as the season progresses. From mid-August until November, he stockpiles brome and clover pasture for winter grazing. During spring and summer, he prefers to graze it down to 4 to 6 inches before moving the cattle off of the pasture, to maintain the residual forage supply and the root structure.
“If you think about the pastures that are really short, they don’t have much root structure underground to utilize the nutrients and rainfall when we do get it,” he says. “If I do a proper job of grazing my brome, I can have it just as lush as the cow can stand in the summer.”
This article published in the March, 2014 edition of WALLACES FARMER.
All rights reserved. Copyright Farm Progress Cos. 2014.