Forage 2022: Burning Issue: How dormant-season fire affects rangeland, crop ground, and what to expect after a fire in the dormant season

Unplanned fires strike fear into every farmer’s and rancher’s heart, but there are ways to mitigate the effects before a fire even happens.  

Dealing with the effects of a fire during the dormant growing season is different than a growing season fire. 

Perkins County, South Dakota saw two dormant growing season fires last year, the Windy Fire, south of Lemmon, in January, then the Divide Fire, west of Bison in late March of 2021. 

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Both fires caused wind erosion, said Ryan Beer, NRCS area rangeland management specialist in the Bison, S.D. office.  

“For the crop ground that burned, it blew really bad,” he said. And some of the rangeland ground that burned ended up blowing in places, too, depending on how sandy it was. 

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Weather conditions after a fire make a big difference on how producers respond to burn.  

“The response to a fire depends on the moisture you get afterwards,” Beer said. With little to no precipitation after the Windy and Divide Fires, and because most of the plant species are cool season grasses in the northwestern part of South Dakota, Beer said they didn’t get much growth on it. 

In a perfect situation, after a dormant season fire, there’s “one of those snows that fall pretty, with snow cover, and not a lot of wind. That’s better than when you have a lot of wind and there’s no snow cover,” said Emily Helms, South Dakota NRCS state rangeland management specialist. “In that kind of winter, you might have a lot longer recovery time.” 

In Perkins County, the NRCS got funding for Environmental Quality Incentives Program (EQIP) projects in Perkins County, to pay for season-long and early summer deferment, so producers could let the ground rest and recuperate.  

The best response for ranchers was to not turn cattle to graze until October, when there was more growth. For farmers, it was to plant as soon as possible, to cut down on wind erosion. 

But a lot depends on the condition the rangeland was in, prior to the fire.  

Rangelands that are in good condition, healthy, and well-managed will respond better the next spring than pasture that’s been over-utilized and grazed to the ground with not a lot of ground cover. Those pastures that have been used heavily won’t respond as quickly, Helms said. 

She also noted that ranchers who rotationally graze appropriately might see improvement faster than someone who puts cattle out on the same pasture for the entire summer. The new growth is “super-palatable, so (cattle) will go after it really hard and that will set it back even further.” If producers put cattle back out in the fall, they should be careful to not graze it all. “Leave stubble so it catches snow and can recover.”  

Fire seemed to decrease the amount of Kentucky Bluegrass, which has invaded in recent years. Beer and Jessalyn Bachler, an SDSU rangeland specialist, studied a few spots to see if there was less of it. “Where the burn was showed a decrease in the amount of Kentucky Bluegrass after the fire,” Beer said. “But there was a decrease in total production, too.” 

As for crop ground, a dormant season fire causes a decrease in production, but the time of year also makes a difference. Beer said that crop ground burned in the January fire had more time to erode than crop ground burned in the March fire, which was closer to the growing season. Overall, there was a decrease in production, and he attributes that to wind erosion and a decline in soil health. “The soil structure definitely went backwards in stability.”  

Beer, a rancher himself, had ground seeded to warm season grasses, and he noted that those grasses seemed to come back better than the cool season grasses, which is predominantly what is native to northwest S.D.  

But he, along with others, thinks the native plants will come back better.  

Helms said the “weeds” don’t disappear just because of the burn. “If they were there before, they’re going to be there afterwards. They may take advantage of the situation.” She cautioned against too much spraying to get rid of them. “You might see a flush of weeds, but monitor it. Don’t knee-jerk spray everything, because you’ll spray out the native flowers as well. Do some spot spraying and mowing. It’s more a wait and see before you decide to spray.”  

Hay is often donated to those in areas where fires occurred, and there are things to keep in mind when feeding it, said Dr. Roxanne Knock, a staff nutritionist at Dakotaland Feeds.  

“We always want to test the hay,” she said, “to see the nutrient value we have. Then we fill in the gaps and try to figure out how to supplement.”  

Protein is usually the needed supplement, and it can be added with alfalfa, protein tubs, distillers grains or high quality hay. If energy is lacking, silage and grain can be added.  

Cattle might get by with poor quality hay for a while, if they’re not near calving time, but as calving approaches, those cows need good nutrition.  

“I’ve seen issues where people didn’t test their hay and didn’t know its quality,” Knock said. “They had weak calves, and it takes a tremendous amount of effort to get them going when they’re born weak.” 

Another consideration with donated hay is the unwanted plant seeds it brings in. Many producers feed the donated hay in a lot and can monitor what introduced plants grow. “People are concerned about it so they try to feed in the same areas, so they can manage it better,” Helms said.  

Pete Bauman is the “fire guy in South Dakota,” according to Beer and is the SDSU Extension Field Specialist for natural resources and grazing.   

“Pyro Pete,” as he is affectionately called, said that if rangeland is healthy, it can withstand a fire.  

“What we seem to be re-proving, is that the healthiest native rangeland can take and often thrive with a fire event. These prairies are adapted to fire. We shouldn’t be surprised, although it seems like we always are, that grassland is fine,” after a fire.  

But the caveat, he said, is the definition of healthy rangeland. “Oftentimes the healthiest are the native, virgin, with a healthy native plant community that isn’t overgrazed. 

“But it’s not magic, either. If a dormant season fire does occur, the native rangeland shouldn’t be stocked with cattle until it’s recovered, but the recovery time is often quicker.”  

Fire collateral and response varies with the soil type. 

Northwestern South Dakota “is a much more brittle landscape than the hills of eastern South Dakota,” he said. “Should a dormant season fire occur in the east, which is rare, the soil stability probably wouldn’t be much of a concern. 

“The impacts of intensity, duration, timing, scale and location matter as to how fire plays to the short-term and long-term impact.”  

Fire is natural, Helms pointed out. Before European settlement, “fires came through all the time. Fire and grazing are what shaped this part of the country.”  

Bauman said it’s important that the fire community supports and acknowledges that unplanned fire is never good, “because of the impacts to operational finances, assets, and life.  But, ecologically speaking, there can be some positives of wildfire on healthy native rangeland if it does occur. Pastures will likely green up earlier and produce more tonnage and healthier seed, and if the seed is allowed to mature, you’ll have tremendous flowering and seed production.  

“You wouldn’t want to wish a wildfire on anybody, because it’s unplanned. The grassland is resilient and will likely respond and flourish from the event. Grasslands are adapted to fire in all seasons,” he said.  

“Oftentimes, fire will wake up plants that have been dormant in the system that might need a crazy stimulus like a dormant season fire. There’s something inherently natural about the prairie burning once in a while. It’s the beauty of the resiliency of the system.”