VERNON - Research under way at The Texas A&M University System’s Agricultural Research and Extension Center here may one day help Rolling Plains cattle producers fill the gaps in their grazing season.
Wheats bred for forage and grain production are a staple crop for many producers on the Rolling Plains. They provide forage throughout the fall and spring grazing season, and a grain crop come summer. But they produce little forage in late fall and early winter, and provide no summer grazing at all.
Cattle producers typically fill the winter and summer grazing gap with supplemental feed and hay, which can prove expensive.
“The long-term goal of our research is to develop sustainable systems that employ several types of forages,” said Dariusz Malinowski, Texas Agricultural Experiment Station assistant professor-forages based at Vernon. “We are looking at dual purpose wheats and other small grains, introduced cool-season perennial grasses, warm-season annual and perennial grasses, annual legumes and alfalfa.”
A native of Poland, Malinowski earned his doctorate in natural sciences in Switzerland in 1995. He studied tall fescue forages from 1996-1998 as a visiting scientist at the USDA Agricultural Research Service Appalachian Farming Systems Research Center in West Virginia. He conducted his post-doctoral forage research at the Vernon center from 1998-2000 and has led the forage research program here since 2001.
“This is a challenging climate for forage production,” Malinowski said. “Most rainfall occurs in May and September. In between there is extreme heat and moderate to severe drought. At first, we tried several species of improved introduced cool-season perennial grasses. They can survive the winters here, but not many could survive the extreme summer heat and prolonged drought.
“Then we looked at drought tolerant species. But they did not produce much forage early in winter grazing season and they had poor persistence. We had to reseed them each year.”
In 2000, Malinowski decided to take a new tack.
While in Switzerland he had seen cool-season perennial grasses native to the Mediterranean Basin that yielded well in winter and went completely dormant in summer. Would they grow here, he wondered?
“The severity and duration of summer drought in the Mediterranean Basin is very similar to what we experience here on the Rolling Plains. The cool-season perennial grasses that evolved there just might work here,” he said. “As the days grow longer and temperatures rise, these grasses go dormant and stay dormant regardless of soil moisture. This is called obligatory summer dormancy.
“They break dormancy and begin to grow again when the days grow shorter and temperatures drop, about the time that autumn rains begin to fall.”
Malinowski planted two such grasses, Grasslands Flecha tall fescue and Maru harding grass, in 2000. They yielded well in clipping trials and survived severe summer drought in 2001.
In 2002, other types of summer-dormant tall fescues, harding grass and orchardgrass developed in Australia and New Zealand were added to the trials.
All of these grasses survived drought conditions in 2002 and a severe summer drought in 2003.
“These grasses go dormant beginning in late-May or early June, and then break dormancy in September. They put on good growth and managed to survive dry winter conditions,” Malinowski said. “They obtain their peak growth from January through March, and produce nutritious forage during that time.
“After four years of severe clipping trials, their persistence is good…they are still holding their own. They can withstand severe defoliation, persist and regrow in this climate.”
Malinowski’s 2004 evaluation trials will test these grasses’ ability to withstanding different amounts of grazing pressure. Larger grazing plots will be planted and stocker cattle provided by Bill Pinchak, Texas Agricultural Experiment Station ruminant nutritionist, will put these forages to the test.
“We want to see how they respond to different stocking rates, and how the cattle will perform,” Malinowski said. “We think it may be a good idea to withhold cattle during the first grazing season after establishment, but that remains to be seen.
“Withholding cattle that first season would give these grasses more time to establish a larger, deeper root system. Such a root system is a factor in the plants’ ability to persist and out-perform the summer semi-dormant grasses that have been tried in the past.”
The cool-season, obligatory summer-dormant perennials tested so far have done well on a wide range of soil types, are less expensive to establish and are not fertilizer-hungry.
“We typically seed them at lower rates than dual-purpose wheat, between 18 and 20 pounds per acre or less on sandy soils. Our seed cost ranges from $3 to $5 per pound,” Malinowski said. “We give them about 40 pounds of nitrogen per acre in early fall and early spring, without any supplemental phosphorus or potassium.
“The best yield we have obtained in our clipping trials was 5,000 pounds per acre. The worst yield, during the driest season, was 1,000 pounds per acre.”
During the next few seasons, Malinowski hopes to develop a list of best management practices for these forages.
“We need more information on how to manage these forages. We also plan to add some annual legumes to the mix,” Malinowski said. “We are also evaluating alfalfa cultivars for winter hardiness under limited irrigation, and new dual-purpose wheats developed by Texas A&M small grains breeders.
“Limited water and recurring drought shape our forage and grazing systems here on the Rolling Plains. We are working to develop integrated sustainable forage systems that will give cattle producers a better chance of success in this climate.”