Drought tops questions called to MU Extension

Saturday, May 19, 2018

COLUMBIA, Mo. – Extension agronomist talk was calm on the weekly teleconference. Few problems discussed on bugs, weeds, fungus or other pests. Then the weather hit the fan. Reports from across Missouri told of farmers’ concerns about lack of rain.

For corn farmers it’s the threat of rootless corn. Soybean growers worry about low emergence and uneven stands.

Cattle farmers ask “Where’s the grass? What do we do for hay?”

Some farmers cut and baled winter cover crops. Others look at their heading winter wheat for forage instead of grain.

Most all say send more rain soon. The northwestern half of the state seems to have the least subsoil moisture.

Small rains that fall may do more harm than good. A 0.2- or 0.4-inch rain may be enough to germinate seed but not enough to grow roots, said Bill Wiebold, University of Missouri crops specialist. Without adequate soil moisture, there may be rootless corn syndrome this year. That can lead to downed cornstalks.

There’s also concern about temperatures. “We went from March to July, skipping spring,” Wiebold added.

Earlier updates indicated warm weather and high winds increase evaporation from the surface soil. Also, rain fronts pass through quickly. Spotty showers replace daylong rains.

MU climatologist Pat Guinan had said earlier that the dry subsoil holds few reserves. “This year, crop water must come from the sky, not deep roots.”

Questions about when to cut hay drew a cautious response from Craig Roberts, MU Extension forage specialist.

A dry winter with short hay supply led to overgrazing winter pastures. In spring, grass regrowth slowed in low temperatures.

A long, cold spring put grasses into survival mode. Grass didn’t grow leaves but shot up seed stalks. Plants make seed to go into the soil bank for survival of the species.

If seed stems on most fescue are grazed, cattle get toxicosis. In spring, toxic ergovaline concentrates in the seeds.

A secondhand report told of a veterinarian called to a beef herd that had grazed toxic seeds. Several cows died.

The only hope for renewed forage growth is to clip the seed heads, Roberts said. Seed stem clipping triggers growth of tillers for the plants trying to put out leaves.

But seed clipping won’t help if normal rain doesn’t return. Plants will need rain to regrow.

“If I knew what rains will do in the next two weeks, I could give better answers,” Roberts told regional agronomists online. The weekly MU Extension call-in session answers questions county specialists get from farmers.

“I’ve never seen anything like this,” said Wayne Flanary, agronomist in northwestern Missouri.

Ben Puttler, an entomologist who monitors alfalfa fields in central Missouri, said alfalfa weevil arrived late. But the forage outgrew the leaf-eating pests.

Now most alfalfa is tall enough for the first cutting for haylage or bales. That controls the weevil.

 

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