Stockpiling forage is a proven way to extend the grazing season through the fall and into the winter. Doing so also saves on hay-feeding costs and prevents mud and ruts that would otherwise form around bale rings in a pasture. But given the overtime that stockpiled forage puts in during the offseason, it may need an extended spring break to fully recover.
In a recent article from Ohio State University Extension, Victor Shelton says cool-season forages must be fully dormant before livestock can graze stockpiles. Even then, it is critical to understand the physiological stress that stockpiled forage can endure and the recovery required for long-term pasture health.
“Grazing prior to dormancy places substantially more stress on plants because they continue attempting regrowth, drawing heavily on carbohydrate reserves,” writes Shelton, a retired Natural Resource Conservation Service (NRCS) agronomist and grazing specialist. On the other hand, forage can generally maintain root reserves if it is grazed after dormancy begins. But dormancy does not mean total inactivity.
“Roots and crowns continue to respire, fine roots naturally turn over, and tiny amounts of photosynthesis may occur during mild winter spells,” Shelton explains. “This low-level metabolic activity relies on stored energy, and repeated grazing over extended periods — even on dormant forage — gradually depletes plants’ reserves.”
One controlled defoliation event can usually be tolerated, but when livestock overgraze winter pastures, lower leaves and residual stubble may be removed, exposing essential growing points to cold temperatures and wind. Moreover, buds that would otherwise initiate early spring growth can be damaged or detached, and root systems become even more vulnerable.
“Even if plants appear alive above ground, thin roots reduce water and nutrient uptake as soil temperatures warm, slowing regrowth and limiting the stand’s ability to compete with weeds,” Shelton says. He adds that legumes — particularly clover species — are most susceptible. “The impact is more pronounced because the crowns are smaller, nitrogen-fixing nodules are sensitive to physical stress, and overall energy reserves are lower.”
Prioritize recovery
Despite these risks, stockpiling forage is an important component of many grazing systems across the country. Shelton suggests the key is to rotate or strip graze livestock through stockpiles, maintaining 3 to 4 inches of residual height — similar to grazing recommendations for actively growing pastures. This allows plant crowns to remain insulated, buffers soil temperature swings, and helps preserve some photosynthetic capacity through the winter months. Shelton adds that dormant plants that experience stress from overgrazing won’t show symptoms until spring green up.
In addition to rotational grazing, overseeding forage can enhance winter pasture recovery. Shelton suggests February is an ideal time to overseed cool-season grasses and/or frost seed legumes in Midwestern pastures, giving seedlings a fair shot at establishment before competition from other species ramps up with warmer temperatures.
“Fertility management also supports recovery,” Shelton adds. “Adequate phosphorus and potassium aid root development, while nitrogen applications can be timed once seedlings are established to boost growth without creating excessive competition from established perennials.”
Also consider the impact that different livestock species can have on stockpiled forage. Shelton points out that mature beef cows exert the greatest pressure on dormant plants due to their heavy body weight and selective grazing behaviors. On the other hand, weaned calves generally cause less damage because they are lighter and demonstrate more uniform grazing patterns. “Recognizing these differences allows producers to adjust stocking rates, rotation schedules, and recovery plans according to animal behavior,” Shelton writes.
Overall, his three pillars of stockpile management are: protect plant crowns, plan for recovery, and match animal demands to pasture performance. “Recognizing the subtle, cumulative effects of winter grazing and planning for repair will ensure that spring green up is vigorous, stand density is preserved, and forage diversity is restored,” Shelton concludes.
