by Jim Hoy
ABOUT THIS ISSUE
Published by EMPORIA STATE UNIVERSITY
Prepared and Issued by THE DIVISION OF BIOLOGICAL SCIENCES
Editorial Committee: DAVID EDDS, TOM EDDY, GAYLEN NEUFELD
Editors Emeritus: ROBERT BOLES, JOHN BREUKELMAN, ROBERT F. CLARKE
Typist: NANCY GULICK
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Circulation (this issue): 5700
Printed by: ESU Press
Online edition by: TERRI WEAST
The Kansas School Naturalist is sent free of charge and upon request to teachers, school administrators, public and school librarians, youth leaders, conservationists, and others interested in natural history and nature education. In-print back issues are sent free as long as supply lasts. Out-of-print back issues are sent for one dollar photocopy and postage/handling charge per issue. A back issue list is sent free upon request. The Kansas School Naturalist is sent free by third class mail to all U.S. zipcodes, first class to Mexico and Canada, and surface mail overseas. Overseas subscribers who wish to receive it by airmail should remit US $5.00 per year (four issues) airmail and handling. The Kansas School Naturalist is edited and published by the Division of Biological Sciences, Emporia State University, Emporia, Kansas. Editor: John Richard Schrock, Division of Biological Sciences. Third class postage paid at Emporia, Kansas. Address all correspondence to Kansas School Naturalist, Division of Biological Sciences, Box 4050, Emporia State University, Emporia, KS 66801-5087. Opinions and perspectives expressed are those of the author(s) and/or editor and do not reflect the official position or endorsement of ESU.
PHOTO CREDITS: The photographs in this issue were taken by Larry W. Schwarm, Assistant Professor of Art at Emporia State University. The images were made in Lyon and Chase Counties, Kansas, from 1990 to 1992. They document aspects of day and night burns, of shortgrass fires that barely simmer and the wildness and violence of the tallgrass fires, and they capture the aura and beauty of the spring ritual of pasture burning.
This issue of The Kansas School Naturalist derives from "Fire in the Flint Hills," a multidisciplinary colloquium held at Emporia State University in April 1991.
This issue of The Kansas School Naturalist is underwritten by The Bay Foundation, New York, NY.
ABOUT THE AUTHORS
Dr. James F. Hoy, Professor of English at Emporia State University, teaches a course on the folklife of the Flint Hills.
Elmer J. Finck is an Assistant Professor in the Division of Biological Sciences at Emporia State University. He has extensive experience with fire in the tallgrass prairie and its effects on mammals and birds.
Prairie Fires: Pasture Burning in the Flint Hills
by Jim Hoy
A prairie fire, burning uncontrolled and undirected in the wrong place at the wrong time, can be extremely destructive. A spark from a locomotive, a lightening bolt striking the ground, a match or cigarette tossed from a car window can cause many thousands of dollars worth of damage to livestock and property - not to mention severe damage to the environment. During the dry, windy summer of 1984, for instance, accidental fires broke out in Butler, Chase, and Marion counties, destroying the forage on nearly half a million acres of pastureland before they were extinguished. Small wonder that most people automatically assume that prairie fires are bad.
And yet every spring since the days of early settlement farmers and ranchers in the Flint Hills of Kansas have, in opposition to popular opinion and, until a couple of decades ago, in defiance of scientific advice, deliberately set the prairies ablaze, burning off the old grass so that cattle could have easy access to the new growth. In recent years the efficacy of this folk practice has been vindicated by the experiments of rangeland scientists, who have shown that controlled pasture burning, particularly if conducted in mid to late spring, is an efficient and economic way to maintain a tallgrass prairie. It keeps the pastures relatively free of trees and brush while at the same time promoting better weight gains in livestock.
In fact, there would be no tallgrass prairie without a fire, at least not in the Flint Hills, where the annual rainfall is high enough to support relatively dense stands of trees. Poorly managed pastures, suffering the effects of overuse, soon become overrun with trees - elm and hedge in the southern Flint Hills, red cedar to the north. One defense of fire given by ranchers is that an overgrazed pasture can't be burned. If there is no grass left at the end of the pasture season, there won't be enough for a fire in the spring: graze half, leave half is the rule of thumb. So for well over a century and a quarter blazing pastures, hazy skies, and the faint, sweet smell of grass smoke have been a hallmark of spring on the tallgrass prairie.
Pasture burning as a springtime ritual in the Flint Hills predates white settlement. Early explorers noted the burned prairies and the proclivity of the Osage and the Kansa Indians to fire the dead grass in order to lure bison, antelope, elk, and deer onto the newly greening hillsides - and into range of their arrows and spears. Folk memory among Flint Hills ranchers records that the Native Americans would set the prairie afire by wrapping rawhide around a big ball of dead grass, lighting it, then pulling it behind a running horse. Back then, and in pioneer times as well, with no roads, highways, or large expanses of plowed fields to slow the headfire, a prairie fire would burn from river to river, keeping the Flint Hills free of trees.
Early Euro-American pioneers in the Flint Hills, whether learning from the aboriginal inhabitants or perhaps bringing them with the practice of agricultural burning, soon settled into the custom of a spring burn. Elisha Mardin, for instance, one of the early settlers in the area, who first came to Bloody Creek (now Chase County) in 1858, records in his 1863 diary the deliberate burning of various of his pastures during March (once) and April (five times). Within a dozen years burning was so common in the Flint Hills that the editor of El Dorado's Walnut Valley Times (Butler County) railed against the practice, echoing popular sentiment in blaming prairie fires for drought, scorching winds, grasshopper infestations, failed springs and creeks, and ruined crops. But where members of the general public saw only the devastating effects of prairie fires (particularly if they had lost houses, outbuildings, crops, livestock, or even family members to an uncontrolled fire), Flint Hills graziers saw fresh grass, lush pastures, and contented cattle. By the end of the century many grazing contracts specified that pastures were to be burned so that the new grass would be ready when the Texas cattle arrive in mid-April for the beginning of grazing season.
Today, now that range scientists and ranchers have come to terms on the general efficacy of burning, the major contention between the two groups concerns the appropriate time of year for fires. Some Flint Hills operators still burn in March, a carry-over from the days when aged Texas steers filled Flint Hills pastures. Others, however, follow modern scientific advice in burning from mid-April to mid-May for maximum weed control and forage growth and minimum erosion damage. Also, whereas some ranchers will burn their pastures nearly every year, many others are more likely to skip a year or more between burns. Thus in earlier years someone might set a fire that would burn uncontrolled, and unremarked, throughout many pastures in an entire watershed, say from the Southfork and Verdigris Rivers, to the Cottonwood. However, today, some pasture owners want their land burned early, some want it burned late, and some not at all. Pasture burning has become a more precise and a more time-consuming job. Many ranchers, in fact, consider it the hardest of their various chores, including building fence and making hay.
A typical pasture burn is often a cooperative venture, with workers from two or more ranches involved. One crew will be from the ranch whose pastures are to be burned. The others are from bordering spreads and there to trade work ("neighboring," it is called) or to protect pastures that are not to be burned at this particular time. After listening to the weather forecast, the rancher organizing the burn will notify the others as to the day, place, and time. Ideal burning conditions include warm temperatures and a recent rain (so the new grass will spring up quickly) with a mild to moderate wind blowing in the right direction. Wind coming from the wrong sector or at too great a speed will occasion a postponement, whereas no wind at all, especially when combined with overly dry conditions, will result in a slow burn that can cause damage to both grass and fence posts.
In earlier years equipment consisted primarily of matches to start a fire, a steel-handled rake to spread the fire by dragging burning dead grass, buckets of water, and gunny sacks or old overalls to soak in the water and beat out the fire. Beginning about the time of World War Two, mechanical sprayers became available. Today burning crews are usually outfitted with at least one mechanical sprayer and water tank mounted on a four-wheel-drive pickup or on a trailer pulled by a tractor and some kind of mechanical fire starter (propane torch, drip torch, or firestick). Crews will also carry gunny sacks and water buckets, to put out small fires. Experienced pasture burners carry matches at all times so that, should they be caught in the open prairie with a headfire bearing down upon them, they can start another fire and then step into the burned area and thus escape the main blaze.
When the crews have assembled, the first order of business is usually to set fireguards, thus creating a barrier between the pasture to be burned and adjoining grass that will not be burned that particular day. Typically this barrier is created by setting backfires, unless there is a road or a plowed field to form a natural barrier. If the wind is from the south, for instance, the workers will create fireguards on the east, north, and west sides of the pasture. To create a fireguard in the open prairie or along a fence row, a worker operating a cattle sprayer will lay down a heavy strip of water. Following close behind on the upwind side of this strip will be another worker setting the grass afire. The dry grass will burn into the wet area, then usually go out. To insure that it does, another cattle sprayer or some workers with wet sacks will follow the fire setter, paying special attention to smoldering cow chips that might later rekindle the fire. In the meantime the fire setter has gone back and forth on the upwind side, lighting small strips of grass so that the fireguard is widened beyond the point where the backfire, which is left to burn, can jump the burned area. Once the fireguards are large enough so that a headfire will not jump them, a fire will be set on the upwind side. The headfire will travel quickly throughout the rest of the pasture, until it burns into the fireguards and goes out. Occasionally there will be small patches inside a large pasture that don't burn, protected from the headfire by cattle trails or short grass. These spots are usually fired with matches a day or two later, a practice known as "patching."
Starting a prairie fire is not difficult, but building a proper set of fireguards, and keeping them from escaping into areas not to be burned, requires great mental and physical effort. And luck - a sudden gust of wind or an unexpected change in wind direction has more than once resulted in an escaped fire that has burned not only an unintended pastureland but barns and haysheds as well. Another hazard of pasture burning is getting a vehicle stuck in a mud hole or high centered in a ditch and having to abandon it to the flames.
Pasture-burning equipment and techniques have become more sophisticated over the years, but the results are the same now as they have been since the settlement of Kansas, and for thousands of years before that: a tallgrass prairie that blankets the Flint Hills with a rich variety of grasses and wildflowers.
TO START A FIRE
by Jim Hoy
Pasture burners in the Flint Hills have employed a variety of techniques and folk devices for setting fires. Some ranchers, in a manner related to the Indian method of dragging a burning ball of dead grass across the prairie, have wrapped a log chain around a kerosene-soaked bale of hay (or an old tire) and pulled it behind a pickup. Others have wrapped burlap into a tightly twisted ball, soaked it with kerosene, attached it to a length of heavy wire, then tied the wire to a lariat rope and ragged it behind a horse. A more physically demanding method involves using a rake (often with a metal pipe substituting for its wooden handle) or a pitchfork to pull clumps of burning dead grass along the edge of the pasture to be set ablaze. Regular wooden kitchen matches, broken in half before striking, are often thrown into the grass from the window of a pickup or the back of a horse. (Only half a match is used because a whole match will more often than not lie on top of the grass and go out whereas a broken match will more easily drop down into a clump grass.) One Flint Hills rancher orders special matches with wax-coated oversized heads from a maritime supply house for use during pasture-burning season. Other ranchers have become more mechanized, adapting to their own use such commercially manufactured devices as kerosene weed burners, propane branding-iron torches, and army-surplus flame throwers.
Undoubtedly the most striking bit of folk technology to have emerged from the annual burning of the Flint Hills is a fire starter called variously a firestick, a firepipe, or a firesetter. This device, simple in construction and appearance, is easy to use and effective, although somewhat forbidding, even frightening, to the uninitiated in its makeup: it is nothing more than a length of ordinary pipe filled with gasoline, one end sealed, the other plugged, with a small hole in the removable plug so that the gasoline can drip out and catch fire. To use a firestick, one sets fire to a clump of grass with a match, then drops the plugged end of the firestick into the fire. The gasoline ignites and, as the pipe is dragged along (whether on foot or from the rear of a four-wheeler or the bed of a pickup), the gasoline dribbles and bounces out, setting grass ablaze in a continuous string of fire. To extinguish the firestick, the operator simply turns the drip end skyward and it will soon blaze out, or he can harmlessly smother the flame with a gloved hand.
What keeps a firestick from blowing up? Operators say that for an explosion to occur, air would have to get into the pipe, which it cannot do. Admittedly the device has every appearance of a bomb, but not a single one of the hundreds that are or have been in use has ever been known to have exploded. One rancher, in fact, lost his firestick when it bounced off his flatbed pickup. When he went back to look for it, the prairie fire had burned over it and the heat had caused the gasoline inside to expand and squirt out the drip hole like a geyser. Flames were shooting ten to fifteen feet in the air, but the firestick did not explode.
This record of safety, however, has not induced extension service personnel or university researchers to adopt the firestick. Instead, most of them use the commercially manufactured drip torch for lighting fires. This device is comprised of a canister with handles on the side and a stem extending from the top. A coil in the stem at its base keeps air from getting into the canister, while a wick at the end of the stem drips the burning fuel, a mixture of gasoline and diesel fuel. Drip torches, developed from kerosene flame torches, were first introduced in the early 1950s.
Firesticks came into widespread use in the Flint Hills during the 1970s, but oral tradition records their use back into the 1950s and even beyond. The earliest, in use before World War Two, seem to have been made of kerosene- or gasoline-filled three-quarter-inch pipe with a corncob or rags stuffed in one end for a wick and a thumb held onto the other end. Today all Flint Hills firesticks are homemade, perhaps because the potential market is too small to support commercial manufacture. They come in many different sizes and lengths, with variations reflecting the individuality of their makers - a ring welded onto the sealed end for attachment to a four-wheeler, a shovel-like handle built into the sealed end for easy handling, a cage of iron rod build around the drip end to hold it up and out of the mud or wet cow chips, an upper end of plastic pipe and the lower fourth of metal to reduce the weight.
Pasture burning may be the hardest part of a Flint Hills rancher's job, but the firestick has helped to make it easier.
EFFECTS OF THE FIRE ON ANIMALS
by Elmer J. Finck
The aftermath of a fire looks very devastating with the blackened ash and the landscape apparently void of vegetation. However, within a few days the green sprouts of plants begin to appear. The question is what has happened to the animals? Have they been destroyed by the fire? Is the fire as good for them as it is for plants such as the warm season grasses?
Answers to these questions have been sought over the past ten years on the Konza Prairie Research Natural Area, which is in the northern Flint Hills of Kansas within the tallgrass prairie ecosystem. The fires, which occurred in April, were controlled burns on areas not grazed by cattle (Bos taurus). The animals investigated from the population biology perspective include below ground macroinvertebrates, grasshoppers, earthworms, birds and mammals.
There are three categories of response to fire by a species: 1) fire neutral, 2) fire positive, and 3) fire negative. Whether a species is in one of these three categories depends on the time of the fire within the season, the frequency of fires over time, the extent of the fire, and the intensity of the fire relative to the life history of the animal under study.
Fire neutral species are species that do not show a change in population after the fire relative to population size before the fire, or they show no differences on burned areas relative to unburned areas. Fire positive species show an increase in population size after a fire relative to population size before the fire or higher populations on burned areas than on unburned areas. Fire negative species show a decrease in population size after a fire relative to population size before the fire and have lower populations on burned areas than on unburned areas.
In general those small mammal species that eat leafy materials (folivores) and typically have nests made of leafy material at the soil surface, such as prairie voles (Microtus ochrogaster) and hispid cotton rats (Sigmodon hispidus) are fire negative. Species, such as the western harvest mouse (Reithrodontomys megalotis), that have leafy nests at the surface and are more omnivorous (i.e., eating both seeds and invertebrates) are also fire negative. Fire positive species, such as the deer mouse (Peromyscus maniculatus), hispid pocket mouse (Chaetodipus hispidus), meadow jumping mouse (Zapus hudsonius), and the thirteen lined ground squirrel (Spermophilus tridecemlineatus), eat primarily seeds and insects in habitats that have little cover and nest in burrows under the ground. The diversity of small mammals is highest with an intermediate frequency of fire because both fire positive and fire negative species are present.
Among grasshoppers, fire positive species forage on grasses, while fire negative species are species that forage on forbs. Both of these patterns are modified by the way the grasshoppers overwinter (i.e., as eggs or larvae and where these eggs or larvae are located during the fire). Those species that have eggs or larvae in litter or on vegetation are typically fire negative, while those species with eggs or larvae at or below the soil surface are fire positive. Fire frequency seems to set broad limits to the assemblage of grasshopper species within a local community. The diversity of grasshoppers is highest with an intermediate frequency of fire.
Among grassland nesting birds the only species found to be strongly fire negative is the Henslow's sparrow (Ammodramus henslowii). Some species such as the greater prairie chicken (Tympanuchus cupido) and upland sandpiper (Bartramia longicauda) are fire negative early in the nesting cycle and fire positive later in the nesting cycle (i.e., they rarely nest in burned areas) but take their precocial young to the recently burned areas. Greater prairie chickens will move their lekking ground a few meters to be on recently burned areas. Dickcissels (Spiza americana) are fire neutral because some of the forbs in which they nest are negatively affected by fire and some of the forbs are positively affected by fire. Birds that are nesting during the time of the fire have their nest destroyed, but all renest including greater prairie chicken, ring-necked pheasant (Phasianus colchicus), mourning doves (Zenaida macroura), and northern bobwhite quail (Colinus virginianus). Mourning doves show a negative response to fire early in the breeding season by not nesting on burned areas, but show a positive response later in the breeding season.
Three species of large mammals - the white tailed deer (Odocoileus virginianus), bison (Bos bison), and pronghorn (Antilocapra americana) - can all run from the fire. None of them typically have their young during the spring burning season. All have been shown to prefer foraging in recently burned areas in late spring and early summer and thus are fire positive.
In general, the biomass of below ground invertebrates increases with fire for those groups studied. Below ground macroinvertebrates are more numerous in annually burned areas than unburned areas. Biomass of the native earthworms Diplocardia smithii and D. verrucosa increases with burning, while the biomass of an introduced European species Aporrectodea turgida decreases with fire. This difference in responses may reflect the evolution of the native species and its interactions with fire as compared to the European species.
Fire obviously kills those individuals that are caught in the fire and cannot escape, and slow moving animals are more susceptible to being burned (e.g., turtles and snakes). There are some reports of many individuals killed by fire, but remember that most prairie animals have evolved with these periodic events we call fire and have adapted to the presence of fire. How a species is affected depends on the life history of the animal, the time and intensity of the fire, and the frequency of the fires.
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