May 15, 2009

Soon, as soil and air temperature increases, warm-season grasses will begin rapid growth. Adding the correct amount of nitrogen now will help these grasses produce extra hay or grazing.When determining how much nitrogen to apply, consider several factors.

• Will you actually use the extra grass to graze more cattle or increase hay yields? It's surprising how often we apply fertilizer, but waste the extra growth through poor grazing management. Unless you plant to economically harvest extra growth as hay or with livestock, don't fertilize.

   

• Is your warm-season grass likely to yield more when fertilized? Taller warm-season grasses like big bluestem, switchgrass, and indiangrass will respond to nitrogen better than shorter grasses like little bluestem, sideoats grama, or blue grama.

   

• How should the rate be adjusted to account for moisture conditions? In eastern Nebraska, 50 to 60 lb of nitrogen per acre works well for average or better moisture conditions. In central and western Nebraska only subirrigated meadows have enough growth potential to respond to added nitrogen. In these areas about 40 lb of nitrogen per acre will do.

   

If you can benefit from extra growth on warm-season grasses, fertilize in late May for high yields and then graze or cut on a timely basis for profitable returns.

Bruce Anderson
Extension Forage Specialist