Knife River Indian Villages' Spring 2023 Prescribed Burn

Prairie burned to renew it and to clear hazardous fuel near the Big Hidatsa village site. NPS photo.

On May 15, 2023, fire crews carried out the spring prescribed burns at Knife River Indian Villages National Historic Site.

Who was there

The National Park Service's Border Parks Fire Management Zone, based at Theodore Roosevelt National Park, led the operation. Alongside its qualified firefighters and equipment were:

• the Black Hills Fire Module, based at Wind Cave National Park;
• fire staff from Grand Teton National Park;
• the North Dakota Forest Service;
• Knife River's own park staff.

What burned

Crews burned approximately one-fourth of the 1,758-acre park — 450 acres — in four units: Big Hidatsa, Big Hidatsa East, Running Deer and North Prairie. These are only some of the areas the park's fire management plan marks as suitable for prescribed fire.

A burn goes ahead only when the day's weather falls inside set limits, the "prescription." Humidity, wind speed and wind direction are among the factors weighed. On May 15 conditions stayed within those limits, so all four units could be burned one after another. Smoke was not a problem: the wind lifted the column well and spread it out.

Smoke from the May 2023 burn, seen from a distance. NPS photo.

Why burn a prairie

Fire is a central tool for managing prairie. Park managers chose prescribed fire together with reseeding native grasses as their preferred way to restore native prairie in these areas. Fire can also:

• clear fuel from around buildings and away from cultural resource sites;
• maintain habitat for listed species and keep historic scenes as they were;
• restore grassland and help control exotic species;
• restore or maintain natural vegetation, and cut unusually heavy fuel loads across the park.

Research plots inside the burn units let park scientists record how fire affects native and non-native plants.

First results

Dan Angelo, assistant fire management officer for the Border Parks zone, gave his impressions after the burns. Smooth brome, a non-native invasive grass, had grown far enough that he was sure the fire had set it back enough to stop it seeding that year, giving native grasses and forbs an advantage. Small trees and shrubs spreading into the prairie were damaged too, many of them "top-killed," which keeps the prairie closer to how it lived with fire historically.

Restoring the prairie may be the main reason to burn, but it also lowers the risk of a catastrophic wildfire. Where dead and fallen trees had piled up, Angelo said, the fire consumed much of the material on the ground, so it would not build up and make any future wildfire harder to fight.

Encroaching woody plants cut back by the burn. NPS photo.

Sources

Rewritten from the National Park Service article "Successful Spring Burn at Knife River Indian Villages NHS" (public domain), in hubnx's own words.