Bridging the gap with cool season annual forages

Farm Forum

BROOKINGS – Two questions plague livestock producers when it comes to 2013 feed supplies due to the drought conditions, says Warren Rusche, SDSU Extension Cow/Calf Field Specialist.

“In spite of the amount of moisture we’ve received because of the recent storms, there are still questions as to how much production can we expect from range and pasture resources, and will there be sufficient moisture during the growing season to produce full-season cash crops,” Rusche said.

This uncertainty is leading producers to consider alternatives to increase their forage production under limited moisture conditions.

One option which Rusche says deserves serious consideration is planting a cool season forage.

“These are typically a small grain – oat, wheat, or barley – either alone or in combination with a cool season legume like field peas,” he said. “These would be planted in early spring and be ready to be harvested as hay, silage, or through grazing; by early summer.”

These cool season crops should provide additional forage very quickly, early in the growing season to help bridge the gap in pasture production. The early spring moisture that’s been received across South Dakota should be enough to support the early growth necessary to produce early forage.

“They also don’t require as much moisture because most of the vegetative growth occurs before the peak of the summer heat,” Rusche said.

Forage yield trials with small grains have shown that dry matter yields range from 1.5 to 2 tons per acre when harvested at the boot stage, and up to 3 to 4 tons when harvested at the milk stage.

“As with any forage crop, there is a trade-off between yield and quality as maturity advances,” he said.

Rusche points to a yield trial at the Northeast Research Farm which showed early harvested oats (boot stage) tested about 15 percent crude protein. If harvest was delayed until the soft-dough stage the protein content was reduced to 10 percent, but the yield increased from 2 to 3.8 tons per acre. Adding field peas to the oats resulted in an increase of crude protein by about 4 percent – with a slightly lower dry matter yield.

A key advantage these crops offer is flexibility.

“Depending on when the forage was harvested and how much moisture we receive, it may be possible to plant a second crop in that field; either a summer annual for additional forage or possibly a short-season oilseed (sunflowers or very early maturity soybeans for example) as a cash crop,” Rusche said. “Waiting to plant a winter annual either for forage or grain is another option if moisture conditions won’t support an additional summer crop.”

Factors to consider when planting cool season forage crops:

· Prior crop history, especially past herbicide usage is a concern. Products such as atrazine may significantly limit the ability to plant certain crops.

· Residual nitrate-nitrogen needs to be considered as that will determine how much, if any fertilizer would needs to be applied. For more information on sampling soils following a drought please read

· Be cautious when applying high levels of nitrogen fertilizer to a planned forage crop. Small grains are notorious accumulators of nitrates and excessive nitrate levels could render the forage useless.

· Pea/small grain mixtures lend themselves much more readily to silage. The pea vines can be very difficult to get dry enough for hay unless a crimper is used.