Grazing After the Growing Season

Extending the grazing season can help reduce costs for producers.
By: Roger Gates, Professor & Rangeland Management Specialist, SDSU Extension

Providing feed for the cowherd represents the largest expenditure in a cow-calf operation and winter feed is the single largest expense in most operations. In light of this season’s favorable growth, what management strategies could be employed to reduce winter feed expenses with a view to improve profitability? Grazing is generally the least expensive way to harvest available feed, so the opportunity to expand the harvest of this year’s abundant supply is worth considering.

Inventory Winter Feed
Developing a feed inventory at the end of the growing season is straightforward – it’s already accumulated. There’s no need to attempt to anticipate what future conditions may deliver, as is necessary in the spring. A Northern Great Plains cow-calf operation must include some inventory of hay – few winters in this region allow uninterrupted grazing. A strategy which identifies access to feed resources for a "worst case" winter is prudent. This might include hay on hand, hay which could be purchased if needed, and supplemental grain, either owned or available.

Beyond harvested and purchased feeds, inventory of winter grazing likely includes pastures that were designated for winter grazing at the start of the season, but might also include areas that were unused or under-used because of abundant growth. Such conditions may exist on your own property, but might also be available for lease on neighboring properties. The most straight-forward and precise approach to quantifying feed available from potential fall and winter pastures would be to do some clipping. A limited amount of clipping can serve to "calibrate" visual estimates of even the most experienced grazier. Knowing the quantity of herbage available is the starting point for calculating how long a pasture can be grazed and by how many animals.

Protecting Vegetation Resources
It is often suggested that winter harvest is less damaging than grazing during the growing season, but sticking to a more conservative target is a good practice during the winter as well. Dormant plants are certainly less susceptible to damage from grazing than actively growing plants. However, careless decisions made during the winter can be just as damaging as any other time. Since growth has been completed for the year, assessing the forage available for winter grazing is straightforward. The efficiency with which available forage is utilized tends to be lower during the winter, however. Loss of leaves from dry dormant plants from weathering and disturbance is more rapid and severe than for growing plants. Snow cover will also limit harvest of dormant plants. Area allocated for winter grazing must therefore be greater than during the growing season, some experts suggest doubling the area. Risks of overgrazing, exceeding the "take half, leave half" rule of thumb, are as important during the winter as any other time. While the plant is not actively growing, the importance of residue in providing thermal protection and maintaining the surface structures, such as crown buds, that will initiate growth in the following spring, remains critical.

Nutritional Value
In addition to the quantity of available feed, knowing its nutritional value is essential. Nutrient content of dormant forage is generally adequate, especially for the needs of a mature, dry cow. Recently weaned, growing animals have higher nutritional needs, but even they can be maintained and grow slowly on dormant forage that is allocated appropriately. If the rationale for winter grazing is to limit costs, expenditures for supplemental feed should be minimized. Protein is likely to be the first limiting nutrient in dormant pasture. Needs for supplementation will increase as nutrient demands increase, particularly for a pregnant female. Testing the nutrient content of the vegetation animals are selecting provides the best guidelines for determining needs for supplementation. Visual "estimates" are really not useful in evaluating nutrient content. A much better practice is to clip or hand pluck vegetation most likely to be consumed by cattle – concentrating on leaves and upper portions of the plant. Chemical analysis of samples provides guidance to develop supplementation plans that meet, but don’t exceed the delivery of expensive supplemental nutrients.

Fall or winter grazing may also provide opportunities to "add value" to the dormant forage. Many operations will make decisions about cows to cull during fall weaning. Because most culls are sold immediately, lowest prices for cull cows generally occur during this fall period. Retaining cull cows and grazing them through the autumn and at least part of the winter may allow later sale at higher seasonal prices. After weaning, cows will generally gain weight and condition which will also contribute to increased value. Purchasing additional culls to harvest underused pastures might also increase revenue.

Adding Value to Dormant Season Pasture
Operations that traditionally sell calves immediately after weaning might consider delaying that sale, again as a mechanism to add value to available pasture forage, grazing yearlings through part of the winter. Retaining yearlings to graze next summer provides much greater flexibility than immediate investment in breeding females. If growing conditions are favorable next year, yearlings could be retained for all or part of the spring and summer. If not, they can be liquidated.

Winter grazing requires prudent planning. Provision must be made for adequate water accessibility, protection from severe conditions and contingency plans to provide feed during blizzards or heavy snow cover. Nonetheless, grazing dormant pasture could provide an alternative to reduce winter feed costs.