Dakota Lakes Research Farm, Pierre, S.D., has integrated livestock into its no-till cropland in three ways, according to Cody Zilverberg, range scientist and agroecologist at the farm:
1. Added perennial grasses to the crop rotation. The farm is trying a 20 year rotation — five years of perennial grasses followed by 15 years of grain crops.
Dakota Lakes researchers and technicians seeded the first dryland field selected for the perennial phase of the rotation to switchgrass and a small amount of big bluestem. They planted some strips of peas or oats into it as it neared the end of its perennial phase.
The new dryland field that they are planting to grass will have a more diverse seed mix, Zilverberg says. It will be seeded to switchgrass, big blue stem, Indiangrass and alfalfa.
On an irrigated field going into the perennial phase of the rotation, researchers are seeding a mix of alfalfa and orchard grass.
Dakota Lakes also rented a pasture next to the farm that has mostly cool season grasses — smooth brome, Kentucky bluegrass and others. The cows and calves graze the cool season grass early in the spring and summer and warm season grasses later in the summer.
2. Planted cover crops for grazing. Various species are used. In 2020, Dakota Lakes planted pearl millet following triticale and grazed the pearl millet in the early fall while also feeding them the bales.
3. Established winter grazing. From Oct. 31 to April 31, cows graze cornstalks and swaths of an oat-barley-canola-brassica-pea cover crop mix.
The cover crop was planted in winter wheat stubble and swathed in late October. The cornstalk and cover crop swath fields are close enough to each other that cows can go back and forth and balance their diets on their own.
Dakota Lakes allotted .78 acres of cornstalks per cow per month and .29 acres of cover crop swath per cow per month.
The cows calve in the fall. Because the cows need more energy and protein over the winter than cows that calve in the spring, Zilverberg supplements the cows’ ration with 66 pounds of concentrate per cow per month. The concentrate consists mostly of field peas, flax meal and soybean meal. They also provide about 24 pounds of concentrate per calf per month as creep feed.
Access to the corn stalks and the cover crop swaths is controlled by the position of electric fences. In cornstalks, the fence is mounted on the irrigation pivot. In the cover crop, electric fence is strung perpendicular to the swaths. Both fences are moved every few days to give cows access to new feed.
They also bale graze in the winter to increase the amount of manure and trampled hay deposited in specific areas.
Dakota Lakes sets aside approximately 100 pounds of hay per cow per month over winter. The hay is mostly fed when the cows are moved off the cropland on days in the spring when the soil is wet on the surface and frozen underneath.
The cows have maintained their weight and breed back well, and calves have grown well, Zilverberg reports.
FALL CALVES: The Dakota Lakes Research Farm has a falling calving beef herd.
In 2019, the calves’ 205-day weaning weight averaged 525 pounds. Weaned calves have gained 1.48 pounds per day between April and July. Heifers gained 1.61 pounds per day from July to October.
Having cows on the cropland part of the year hasn’t hurt grain yields. No deep soil compaction has occurred. Some compaction in the top 3 inches of soil has been measured, but it disappears quickly. There is little sign of hoof rutting, Zilverberg says. The thick layer of crop residue that covers the soil seems to provide a cushion.