Amanda Grev, Forage Specialist
University of Maryland Extension
It’s August now and whether or not we’re ready cooler temperatures are just around the corner and it’s time to be thinking about winter feeding strategies. Using harvested forages for winter feed represents a substantial expense for livestock operations. For many grazing operations, stockpiling can be an effective strategy to extend forage resources further into the fall and winter season, reducing the costs associated with harvesting and storing feed and providing high-quality pasture for fall and winter grazing.
What is stockpiling?
The concept of stockpiling is simple. Rather than cutting, drying, and storing hay to feed over the winter, existing pastures are allowed to grow and accumulate forage in the field to be grazed by livestock in a later season. Under this management strategy, grazing animals are removed from pastures in late summer and forages are allowed to accumulate growth through the late summer and fall. The cool, late-season temperatures make it possible for the accumulation of high-quality forage even after an extended period of growth. This stockpiled forage is then available for grazing throughout the fall and winter months, reducing the costs associated with feeding stored feeds.
Which forages work best?
Although a number of different forages can be stockpiled, some forage species will hold their nutritional value longer than others in the winter months. Compared to other cool-season grasses, tall fescue is well adapted for stockpiling, as it has the ability to accumulate a substantial amount of fall growth and tolerate colder temperatures without losing quality. In addition, the waxy layer or cuticle on the leaves of tall fescue make the plant more resistant to frost damage or deterioration. Tall fescue also forms a good sod, making it more tolerant to foot traffic and minimizing impacts on its productivity the following season.
How is stockpiling accomplished?
Early August is the time to begin stockpiling for fall and winter grazing. To prepare for stockpiling, pastures should be grazed (or clipped) down to a 3 to 4 inch stubble height to ensure that the accumulated forage will come from new growth. After livestock are removed, 40 to 60 pounds of nitrogen fertilizer should be applied to stimulate additional regrowth and optimize forage accumulation and quality. The grasses should then be allowed to regrow until forage growth dramatically slows or ceases completely.
It should be noted that not all nitrogen fertilizers will be equally efficient when fertilizing pastures in the fall. In urea or urea-based fertilizers, the ammonia is volatile and a substantial amount of the nitrogen from these sources will be released to the atmosphere via volatilization when applied during the hot and humid days of late summer. To minimize this volatilization, these nitrogen sources should be applied immediately prior to a significant rainfall event. Ammonium nitrate is the most efficient source of nitrogen for stockpiling, but it is often more expensive than other sources.
Will yield and quality be good?
Where tall fescue was successfully stockpiled, yields of 1 to over 1.5 tons of dry matter per acre have been documented. Higher yields will be achieved if nitrogen is applied immediately after the last cutting or grazing compared to pastures that did not receive fertilization or were fertilized later in the fall.
Forage quality of stockpiled tall fescue can be very good. Depending on how much nitrogen has been applied, fall-grown tall fescue can average 12 to 18% protein and maintain good nutritional value throughout the fall season. Research has demonstrated that stockpiled tall fescue has sufficient quality to carry dry cows through the winter and could carry lactating beef cows into January without additional supplementation. However, the forage quality and digestibility of stockpiled forages is variable and will decline as growth accumulates, forages mature, and winter conditions continue. To confirm nutritional value, forage samples should be taken and analyzed to ensure the pasture is meeting the nutritional requirements of the animals utilizing it.
How to utilize stockpiled forage?
Stockpiled forage can be valuable under a variety of grazing methods, but forage utilization can be increased substantially by using improved grazing practices. If livestock are allowed to continuously graze the entire pasture with unrestricted access, efficiency will be lower and the potential grazing period will be shortened due to waste and trampling damage. To minimize waste and get the most from stockpiled forage, pastures should be either rotationally or strip grazed. Strip grazing is a management system that involves giving livestock a fresh area of pasture every day or every few days by moving a temporary electric fence in the pasture. This method limits the area available for grazing, helping to increase pasture carrying capacity and maximize forage utilization.
Summary
Removing livestock and fertilizing pastures or hayfields in late summer will allow forage growth to be stockpiled for late fall and winter grazing. Utilization of stockpiled pasture is an economically-advantageous management strategy that will extend the grazing season, minimize winter hay feeding and stored feed requirements, and provide high-quality forage without negatively impacting the persistence of forage stands.