UNL offers grazing management strategies following wildfire

University of Nebraska-Lincoln (UNL) Extension Range and Forage Specialist Jerry Volesky describes grazing management techniques following a wildfire in a UNL Beefwatch article posted on Feb. 27.

With drier conditions, dry, brittle vegetation has fueled wildfires and gone up in smoke on hundreds of acres of range and pastureland in the western half of Nebraska this spring as wildfires rage across the Midwest. 

According to Volesky, wildfires occurring on range and pasturelands happen when there is the right combination of high winds and low humidity.  

“This has been the case here in 2024, and the threat will continue until we have new, green grass growth later this spring,” he states.

Although the aftermath of a fire can look quite devastating, perennial pasture grasses are resilient and will recover, especially since they are still dormant.  

However, he says spring is a time when many prescribed burns are conducted but adequate moisture from spring to early summer is key for pasture growth whether it was burned or not.

Key impacts

“One of the key impacts of a wildfire is the loss of plant residue and litter which protects the soil surface. This residue is important for reducing wind and water erosion and the loss of soil moisture,” Volesky says. “This plant litter and residue is particularly important on sandy soils as high winds following a fire can led to scouring erosion around the plants.” 

According to UNL research, nitrogen and sulfur in the residue would have been lost due to wind, while phosphorus and potassium in the residue would have remained in the ash, if ash is still present on the field and not removed by wind. 

Research at UNL discovered the nutrient content within the residue would not need to be replaced for this year, particularly regarding nitrogen, as the carbon-nitrogen ratio has changed and more mineralization could occur. 

What was not conclusive in the research was the impact on microbes due to fire, and it’s recommended to not focus on nitrogen needs now but to get something planted if at all possible.

Grazing management recommendations following a wildfire is to delay turnout, possibly as long as one month, but can be adjusted depending on rainfall, allowing grasses to accumulate more growth before being exposed to grazing.

Volesky adds, “Stocking rates should be reduced, with the objective of leaving adequate residue, which will become litter on the ground replacing what was lost in the fire.”  

May and June rainfall will be critical and should be used as the guiding factor for many management decisions.

“It is not uncommon to see more annual weeds show up in a pasture after a fire. While this may look concerning, these weeds can actually be useful and have some forage value or will turn into residue and cover at the end of the season,” he says. “Their numbers will decline the following year.”

Fire damage 

Fence damage may curtail any grazing management plans but many pastures may have been only been partially burned.

“On a pasture which has been partially burned, studies have shown cattle prefer to graze the burned portion, resulting in much heavier grazing on the area compared to the unburned portion. Temporary fencing to exclude burned areas early in the season may be a solution, but is often impractical,” Valesky remarks. 

Pasture areas may have been disked to create a fire break, and if the disking was significant where it killed most of the grasses, reseeding these areas using the same grass species found in the rest of the pasture many be warranted. 

UNL CropWatch explains if this cannot be done by the end of May, a summer annual forage crop could be planted as a cover, and then growers can plan to reseed the perennial grasses next spring.

But, the greatest benefit for vegetation following a fire will be a complete growing season rest, perhaps grazing again after vegetation is dormant in the fall. 

Not grazing the year following a wildfire will provide necessary litter to cover the soil surface, and if an area must be grazed, delaying at least until important plants have reached maturity and set seed will be beneficial. 

Planting tips

UNL Extension reports fires have been a common historical occurrence in grasslands, but many herbaceous plants quickly recover after fire. 

A team at UNL analyzed wildfires which burned across the Great Plains between 2000-12 and discovered vegetation rapidly recovered after wildfire, even when fires burned under extreme drought conditions. 

Regions expected to be particularly vulnerable to wildfire, like the Sandhills, have been found to fully recover above-ground biomass within two years of wildfire and extreme drought.

Planting an annual forage system is an option, UNL Extension suggests, particularly for those with livestock where forage resources were lost to the fire. 

UNL Extension further notes, should it be a dry season, drought impacts to forage production are more important than the wildfire, and the UNL Drought Management Planning page provides a variety of helpful resources for developing a drought management plan.

However, for rangelands reseeding is not recommended. Research from the Great Plains shows dormant-season fires do not reduce forage regrowth and grassland vegetation quickly recovers following fire.

UNL Extension reminds land managers and producers to replan their grazing or haying year differently as a result from fire.

Melissa Anderson is the editor of the Wyoming Livestock Roundup. Send comments on this article to roundup@wylr.net.