Konza Prairie Research Shows Ecological Benefits of Burning 3/3/04

MANHATTAN, Kan. – Soon the prairie will be alive with fire, and research shows that those fires can start even earlier than most people realize.

“Fire is not just beneficial; it’s absolutely essential in maintaining the health of the prairie,” said David Hartnett, professor of plant ecology with Kansas State University Research and Extension. “Our research is showing that you can burn much earlier than previously thought and still get the benefits you’d expect from a controlled burn later in the spring,”

As the director of the Konza Prairie Biological Station, located in the Flint Hills of northeast Kansas, Hartnett leads a team of researchers who have been studying prescribed burning and its effect on the prairie since 1973.

Konza Prairie Facts

MANHATTAN, Kan. – Kansas’ Konza Prairie Biological Station is predominately native tallgrass prairie, sometimes called bluestem prairie. It provides a unique outdoor laboratory, set aside for long-term research. Some facts about the Konza include:

* Founded in 1971 under the leadership of Kansas State University professor Lloyd Hulbert.

* Encompasses 8,616 acres or 3,487 hectares. Several adjoining tracts, including the historic 2,923-hectare Dewey Ranch, were purchased between 1971 and 1979. The Nature Conservancy purchased the station lands for K-State with funds provided by Katharine Ordway.

* Is owned by The Nature Conservancy and Kansas State University and operated as a field research station by the K-State Division of Biology.

* Is primarily used for ecological research, including the effect of fire, grazing and climate patterns on the prairie and its watershed areas.

* Has headquarters in a large limestone ranch house built in the early 1900s for the Dewey Ranch, which later became part of the Konza Prairie.

* Is home to more than 600 species of plants and dozens of fish, amphibians, reptiles and mammals.

* Is home or the resting point for more than 200 species of resident and migratory birds.

* Has 14 miles of hiking trails, open daily from dawn to dusk, weather and conditions permitting.

From the days when Smokey Bear reminded, “Only you can prevent forest fires,” some people have had the perception that all fires are destructive, Hartnett said. But scientists have come to understand the ecology of burning and the beneficial effects that a controlled (prescribed) burn can have on grassland in maintaining its productivity and biodiversity.

“In the Flint Hills, fire is a part of the natural ecology,” he said. “Before man started fires – accidentally or intentionally – lightning sparked fires on the prairies. Those fires were beneficial, as they curbed the growth of non-native and woody plants and invasive weed species and they aided the health of prairie grasses and wildflowers.”

An important finding of K-State researcher Gene Towne is that landowners need not limit their controlled burning to just a couple of weeks during April. In fact, Hartnett said, if conditions are right, prescribed burns can start as early as February and be as late as early summer. Spreading the fires out from February to May means less smoke at any given time in the atmosphere than there will be if everyone burns during a two- to three-week period.

“Our long-term data indicate that the abundance of many prairie wildflowers are increased by summer burning. Burning earlier in the year generates a boost in grass production similar to April burning,” he said.

Before settlers arrived, there were typically two to five prairie fires per decade – roughly one every other year or two on any given part of the prairie, he added.

Burning at least every three years is a necessity, the biologist said. If a landowner goes four years or more without burning, there is likely to be an increase in the number of woody plants and weeds.

It’s also helpful to burn different areas at different times, rather than burning one’s whole property at the same time, Hartnett said.

Folklore has held the idea that ash from fire acts as a fertilizer for the soil. But that’s not quite right, the scientist said. One of the reasons grass production increases after a fire is that fire removes the dead vegetation that provides a layer of insulation to the soil and impedes soil warming. Early soil warming in spring helps stimulate important microbes that release nutrients in the organic matter left in the soil.

Another key component of the Konza research is the study of grazing patterns of bison or cattle and their impact, along with fire’s, on the prairie.

“One of the lessons we’ve learned is that the prairie ... the landscape should be a mosaic,” Hartnett said. Dividing prairie pastures into smaller, managed sections and rotating the grazing and burning activities on those sections are what Hartnett calls “patch mosaic” or “patch management.” The practice results in more productive, diverse and sustainable forage areas.

“A shifting mosaic over time is natural,” he said, regarding the shifting of both grazing and burning areas. “A key advantage of maintaining a mosaic is that fire-sensitive or grazing-sensitive species always have an unburned or ungrazed patch as a refuge to maintain their populations. Fire-dependent or grazing-dependent species are similarly maintained at healthy levels.”

For more information about the Konza Prairie Biological Station, interested persons can go on the Web to http://www.ksu.edu/konza .

K-State Research and Extension is a short name for the Kansas State University Agricultural Experiment Station and Cooperative Extension Service, a program designed to generate and distribute useful knowledge for the well-being of Kansans. Supported by county, state, federal and private funds, the program has county Extension offices, experiment fields, area Extension offices and regional research centers statewide. Its headquarters is on the K-State campus, Manhattan.