Several counties in Kansas have been approved by the U.S. Department of Agriculture for emergency haying and grazing of Conservation Reserve Program (CRP) acreage due to the extreme drought and shortage of forage this year.

Several factors are important when haying or grazing prairie hay this summer, said Walt Fick, K-State Research and Extension range management specialist.

“If producers haven’t cut their hay yet, I would encourage them to do so soon.  Harvest date is the most important management decision affecting hay production. Timing affects production, quality, composition, amount of regrowth, and subsequent plant vigor,” Fick said.

Producers should consider raising the cutter bar to leave at least a 3-inch stubble, he said.

Maximum yield of native hay generally occurs in August, but waiting until then results in lower quality, less re-growth, and can alter the composition and vigor of stands if done repeatedly over a number of years, Fick said. Plus, peak yield may have already occurred in drought-stricken counties this year.

The quality of prairie hay will keep declining with time. “Crude protein declines about 1 percentage unit every two weeks during the month of July, and will be no higher than 5 percent by late August when maximum yield normally occurs,” he said.  

The timing of haying on species composition and vigor of stands can also be important, Fick added.

“Repeated mowing around Sept. 1 can change a bluestem-dominated hay meadow to a stand dominated by broadleaf species. The change occurs because the grasses do not have sufficient time to replenish food reserves before frost occurs,” he explained.

Grazing prairie hay this year should be managed carefully, the agronomist said.

“Heavy grazing in late summer can be detrimental to next year’s production. The key is stocking rate. We need to leave enough leaf area so the plants can continue to carry out photosynthesis and store food reserves going into the winter,” Fick said.

How much leaf area is enough? In CRP stands planted with mid-size and tall grasses, a 6- to 8-inch average stubble height, or about 1,000 to 1,500 pounds per acre, would be optimum, he said.

Forage quality will be low in the late season and livestock producers may want to consider how this could affect management of their cow herds, including culling decisions, early weaning, and related practices.