Fall regrowth in wheat fields can provide excellent late-season grazing for beef cows and weaned calves, but it should be tested to avoid potential problems, says Eric Mousel, South Dakota Cooperative Extension range livestock production specialist.

“We have had a couple of light frosts in some areas, but not a heavy killing frost so nitrates are still a concern,” says Mousel. “Cows will tolerate higher concentrations of nitrates than calves, but producers should always test small-grain regrowth for nitrates.”

Most expectations do not point to nitrate problems in 2010, he says, but wheat regrowth is susceptible.

“Regrowth should be sampled in four or five random spots across the field, and then sent in for a nitrate test,” he says. “Samples should be clipped at ground level and put in a sealable plastic bag. The sample doesn’t need to be very big; half a handful per sample is plenty.” Send samples to a private testing lab or to the South Dakota State University Oscar E. Olson Biochemistry Labs, SAS 133, Box 2170, 1029 N. Campus Dr., Brookings, SD 57007.

Grass tetany, also known as grass staggers, is another management concern on wheat regrowth, Mousel notes. “Grass tetany is usually associated with spring grazing; however, it can be a bigger problem in the fall when grazing small grain forage.” Cows and calves that feed on wheat regrowth should be supplemented with magnesium to avoid problems with tetany. He says high-magnesium minerals or other supplements now may be harder to find since grass tetany is typically thought of more as a concern in spring. Producers should source magnesium supplements before turning out cattle on wheat regrowth.