Feeding cows hay now allows grass to recover after long summer drought, say MU specialists

COLUMBIA, Mo. – Feed hay in the fall and save the new green grass for winter. That plan can result in more feed for drought-stressed Missouri cow herds.

University of Missouri Extension specialists urge continued feeding of hay to allow pastures to rebuild root reserves to prepare grass for strong growth next spring.

“It’s tempting to turn cows onto new fall growth when rains return after a drought,” says Rob Kallenbach, MU forage specialist.

There’s another reason to hold off, says Justin Sexten, MU beef nutritionist. Cows will need high-quality grass when winter brings wet and cold weather. The grass growing this fall can be stockpiled in pastures for winter grazing.

“Also, feeding hay in fall is easier than in winter,” Sexten adds. “This winter, cows will harvest the stockpiled grass pasture. You don’t have to start your tractor.”

The save-the-grass message is one of many tips offered at MU field days and farmer meetings. The theme is: “Life after drought.”

At meetings, Sexten demonstrates adding hydrated lime to cornstalks to break down tough cellulose to release nutrients stored in the corn stover.

Also, poor-quality baled hay can be sealed under a plastic tarp and treated with anhydrous-ammonia gas to boost protein content and improve digestibility.

Cows turned into pastures now will nip off grass as it grows, Kallenbach says. That harms pastures stunted by summer-long drought. “Let the grass grow as long as there is sunshine, heat and available water.”

It seems counterintuitive, now that grass growth has returned, Kallenbach admits. But weak stands of grass need fall growth to rebuild reserves for next spring.

During this recovery phase, fall growth can be stockpiled and grazed later.

Sexten adds that fall stockpile grass contains more nutrition than the hay. “Cows will need that higher-quality grass when the weather turns cold.”

Delaying grazing is a win-win, he said. The growth will aid pasture recovery. And more stockpile will accumulate than if the grass is grazed as it emerges this fall.

Pastures that didn’t grow for months during drought will be in weak condition. Many pastures may need renovation in addition to recovery time, Kallenbach says. “Likely there are bare spots and more weeds. That adds to reduced productivity on pastures recovering from drought.”

The MU specialists urge caution in interseeding another grass variety into a weakened stand. Vigorous new growth shades and further weakens surviving grass.

Kallenbach recommends complete renovation if grass covers less than 75 percent of the ground. That may require a yearlong process if converting from toxic endophyte-infected Kentucky 31 to new novel-endophyte fescues that don’t contain toxins.

Renovation must assure none of the old fescue survives in the newly seeded pastures. That requires the proven spray-smother-spray recipe developed at MU. The old surviving fescue is sprayed with glyphosate herbicide to start eradication. Then a winter annual grass, such as wheat or cereal rye, is drilled into the surviving fescue sprigs. This growth smothers most remaining fescue.

Next spring, after grazing or baling the cereal-grain forage, any surviving toxic fescue is sprayed again. Only then should the field be replanted to new grass.

“Toxic fescue is tough to kill,” Kallenbach says. “Those 50-year-old stands have survived more than one drought. If you renovate fescue sod, do it right the first time.”

MU field days and winter meetings are programs from the College of Agriculture, Food and Natural Resources, Columbia.