Impact Of Drought On Forages Will Linger Beyond 2013

UNL grazing specialist says short tap roots feed short roots and short roots provide 'less top' on forages.

Published on: Dec 24, 2012

The aftermath of the drought of 2012 will be felt on grazing land in 2013 and beyond, says University of Nebraska Extension forage specialist, Bruce Anderson. Speaking to farmers and ranchers at the North Central Nebraska Ag Progress Show in Atkinson recently, Anderson said, "Even if we get average rainfall, we're still going to start next year dry."

Producers need to be planning now for next spring, he said. "I don't think all is lost as long as we are prepared," said Anderson. "In drought, leaves don't produce as much and root systems die back. A smaller root system is no longer able to explore the soil profile" for moisture.

According to Anderson, these conditions throw everything into a negative spiral. "Short tap roots feed short roots and short roots provide less top" forage, he said. "We need to relieve the stress above and below ground."

Impact Of Drought On Forages Will Linger Beyond 2013
Impact Of Drought On Forages Will Linger Beyond 2013

The impact of drought on grasslands is substantial. Anderson said that drought reduces forage production, reduces plant reproduction, decreases root systems and thins the plant stand. "It is more severe if past or present practices involve heavy stocking rates or continuous grazing," he said. "The way you've grazed over the past decade influences the root systems that are out there."

He advised producers to pay close attention to thinning stands of desirable grass species and a change in the overall composition of the forages available in the pasture. "Recovery from drought is slow," Anderson said. "The first response is above ground, but the response below the ground tends to be delayed, even with moisture."

Plants often compensate for drought by putting on taller than normal growth above the ground following drought. "There might be more tall growth than we'd normally see," Anderson said. "That abnormal height gives us a false sense of security." Root reserves are low, and this often allows for a change of species in the pasture, moving towards plants that reproduce rapidly. These plants may not be as productive or desirable as those you had before, he said.

Delay turnout this spring and use long recovery periods to overcome drought stress on the pastures, said Anderson. If moisture is available, plant annuals, even on row crop ground, to provide additional forages. "Some of our annuals only need moisture for a relatively short period of time," he said. "So, you may get something."

In the spring, oats works well, according to Anderson. Sorghums, sudans and millets are good summer annuals. If moisture comes in the fall, oats and brassicas like turnips are best, he said.

If you'd like to learn more about managing forages in the aftermath of drought, contact Anderson at 402-472-6237, or email banderson1@unl.edu. Watch for more upcoming drought-related grazing stories in future print issues of Nebraska Farmer.