Regional

Cool weather may decrease forage production, quality

Cooler than average temperatures this spring and continued drought in the northern region of North Dakota have suppressed forage growth across the state, and may contribute to a delay and decline in forage production and quality.

According to grazing readiness surveys conducted by North Dakota State University Extension agents across the state, grazing readiness for cool-season grasses was on track, with the grasses developmentally ready to be grazed by June 1. However, in many areas, growth is lagging behind. In several areas, producers are reporting Kentucky bluegrass heading out at 3 to 4 inches. This is approximately 25% shorter than in a normal year.

Once a grass sets seed, the potential for additional growth, as well as forage quality, is reduced. Grazing in the vegetative stage promotes cell elongation, delaying seed set and preserving forage quality.

“Grasses in our pastures in North Dakota tend to peak in quality early in the growing season,” notes Miranda Meehan, Extension livestock environmental stewardship specialist. “Forage quality quickly declines once seed set occurs in mid-June to early July for cool-season pastures and in mid-July to early August for warm-season pastures.”

A similar delay was seen in alfalfa. Much of the crop in the western half and northern region of the state was not even 6 inches tall by mid-May, which delayed first cutting to the first week of June in eastern North Dakota. However, the first cutting is approximately a week out in western North Dakota.

Following the harsh winter, many livestock producers have experienced inadequate forage supplies. Those who did have forage remaining have been able to delay pasture turnout. Regardless, this decrease in production will affect them.

“One option available to producers is to use prevented-plant acres to produce annual forages for supplemental grazing and/or hay,” says Marisol Berti, a forage and biomass crop production professor in NDSU’s Plant Sciences Department. “If you intend to do this, we recommend not applying for preventive-plant insurance, as you won’t be able to use the forage until Nov. 1. If you do enroll in the preventive-planting program, plant a cover crop that can be grazed after Nov. 1.”

Forage species selected will vary based primary on the planned use: hay, summer grazing, fall grazing or next-spring grazing. Producers still have some time to establish a spring cereal, such as forage oats and barley, that can be utilized this summer. Warm-season forages such as millets, sudangrass and sorghum-sudan hybrids are high yielding and can be harvested for hay, haylage or silage, or grazed.

“Keep in mind that nitrate toxicity is a potential concern for corn, small grains, sorghum-sudan and numerous weed species,” says Kevin Sedivec, Extension rangeland management specialist. “Although people typically associate drought conditions with an increased risk for nitrate toxicity, nitrates can accumulate under other abnormal growing conditions, including above- or below-average temperatures, cloudy conditions or frost.”

Producers have many forage options to plant that can be grazed late this summer through early winter. Foxtail millet, sudangrass and sorghum-sudangrass also can be used as pasture. However, once these plants freeze, livestock tend to be more selective and increase waste through trampling.

Prussic acid poisoning is a potential risk in sorghums and related species with young, rapidly growing leaf tissue or after a frost. The best option is to wait to graze these species until new growth is at least 18 to 20 inches high, and at least a week or two after a frost until forage is dried down thoroughly.

Cool-season cover crop mixtures make excellent pasture well into the early winter period, according to Berti. Cool-season plants are less water efficient and will be more prone to fail if the drought persists. Make sure ample moisture is available in the top soil for plants to establish and grow.

Options for late-season cover crop mixtures include oats or barley, turnips, radish or hybrid leaf brassicas such as Pasja or Winfred. A combination of the species is best. Add a warm-season grass such as millet or sorghum-sudangrass to provide fiber in the diet.

The most common grazing issues that can occur with brassicas include bloat and nitrate toxicity. Forages should be tested for nitrate content prior to turnout, and livestock should be introduced to brassicas gradually during a period of five to seven days. Because brassicas are high in crude protein and digestible energy, they should be limited to less than 50% of the total diet to avoid digestive disorders.

Winter annuals can be utilized for grazing next spring. Winter annuals, winter wheat, winter rye and winter triticale should be planted by mid-September. Winter annuals can be utilized for early season grazing or haylage later in the season.

“If producers are unable to make up for forage shortages, culling animals may be required,” says Janna Block, Extension livestock systems specialist at NDSU’s Hettinger Research Extension Center. “Some culling targets include cows that are old, have poor disposition or physical structure, and those that had a difficult time giving birth this spring and a low chance of rebreeding.

“The importance of records is magnified in times when tough culling decisions need to be made,” she adds. “Good calving and production records can help producers pinpoint cows that could be culled.”