Mark Z. Johnson, Oklahoma State University Extension Beef Cattle Breeding Specialist
During a time of drought, inflation, low hay inventories and high input costs, when I recently checked the price of urea fertilizer and learned it was selling at 43% of the cost of one year ago, I felt like someone had just handed me a winning lottery ticket! As follow up to last week, we dig a little deeper into the importance of fertilization of improved grass pastures. Bermudagrass, Crab grass and Old World Bluestem are examples. First, native range grass pasture is wonderful for beef production. It does not require fertilization, it is resilient, requires less management and input, and with proper management and grazing pressure is more consistent in the amount of beef produced per acre from year to year. That being said, this article addresses fertilization of improved grasses. Improved grasses require intense management, equipment, weed control and with ample fertilization and moisture have the potential to produce higher amounts of forage dry matter and beef per acre than native grasses. The charts below show the level of production that can be achieved (with ample moisture) from improved grasses relative to the amount of nitrogen applied per year.
Relationship of Bermudagrass Yield to Nitrogen Fertilization
Relationship of Old World Bluestem Yield to Nitrogen Fertilization
To summarize, Bermudagrass shows a linear relationship in level of the forage produced to nitrogen applied and a greater production potential than Old World Bluestem, but both respond favorably to nitrogen fertilizer. As covered last week, as we deal with drought stressed pastures be “ahead of the game” in your pasture management plan this year. Apply herbicide to control weeds and fertilizer early to give improved grass pastures the potential to grow all the forage possible when moisture and growing conditions are favorable.
What happens to the nitrogen if we don’t get rain? It is there in the soil ready to provide nutrition to plants when it does rain. As stated in a recent Cow-calf Corner article: “prepare for drought during times you are getting moisture and prepare for moisture during times of drought.” Take inventory of the forage you will need to support your cow-herd this summer. Soil test to see if other macro-nutrients like phosphorus (P) or potassium (K) are needed to feed plants. Fertilize accordingly. You won’t get much production from improved grass pastures without adequate fertilization.