Fertilizing cool season grass pastures
Fertilizing cool season grass is something many producers do each year while accounting for forage needs, moisture, the value of the forage, and fertilizer costs.
Fertilization of smooth bromegrass pastures should occur late March through April. If the nitrogen is a single application, usually between 80 to 100 lbs. of actual N per acre is suggested for eastern Nebraska. The recommended application rate declines westward across the state with about 30 to 40 lbs. N per acre suggested for the Panhandle.
If doing split applications, usually it’s 2/3 in the spring and 1/3 in the fall when growth resumes on the cool season grasses. With fertilized pasture, be sure to include a rotational grazing plan that will effectively harvest the extra forage and provide the greatest return on the fertilizer investment.
Something to consider when deciding to fertilize cool season grass pastures, or any pasture for that matter, is that during drought years the forage quality might still be very high even though yield might be reduced. Again, moisture limits the efficiency of fertilizer.
Research conducted in Eastern Nebraska has shown a 30% increase in forage yield with fertilization and the economic optimum rate is between 80 to 120 lbs. per acre. A crude protein increase from 16 to 20% was seen with fertilizer applications up to 160 lbs. That is a lot of fertilizer, but it did increase crude protein and organic matter digestibility while decreasing NDF or neutral detergent fiber. Always be aware when applying fertilizer, especially in pastures and fields near water sources such as ponds. Assure phosphorous and potassium levels are adequate for forage as well.
Brome pastures are hardy and we can and do graze them hard in Nebraska. Haying or grazing operations can benefit if managed correctly with fertilizer.