Grazing and burning, essays from Bill Whitney

Every so often, I get strong feelings of aversion to cattle grazing.  One reason is because I see many denuded pastures and rangelands due to the limited knowledge a particular cattle rancher has in regards to grazing, ecology, and native grasses.  A lot of people do what I call “hobby grazing” (or complacent grazing), they “run cattle” just to have cattle on their place.  Grazing is not a hobby, it is only a tool to be used when range conditions warrant it.  As a screwdriver is not the tool to frame your new house, neither is grazing the only tool to manage grasslands and prairies.  Another reason is the fact that cattle are not native to North America, and were not large disturbance factors in the evolution of prairies to the extent that bison, elk, and deer were.  Furthermore, why do people feel like they must run cattle on their land or else?  What’s wrong with letting the land become wildlife or pollinator habitat?  After all, those groups of wildlife need the land more than a herd of cattle does.  There are other ways to make money besides cattle ranching or farming, and with droughts in the Plains states possibly increasing in length and duration over the next decade, it may be time to seek other means of income.  Don’t get me wrong, there are a handful of excellent native pastures around here that are being grazed with cattle, but that is not the norm in these parts, unfortunately.

Also, because grazing, fire, and native grasses and forbs co-evolved together over the last 12,000+ years in an ever-changing dynamic across time and space, so too should one’s management techniques.  Those who always graze and never burn are dead set to run into ecological trouble, simply because grazing can never achieve what fire can in regards to soil biota.

While the essays below were written based on the author’s years of experience in Nebraska prairies and rangelands, the concepts discussed therein are applicable to all grasslands in the US.  However, they are in no way an endorsement of what I’ve said previous, I’m simply stating my opinion and sharing these essays.

Note: for further reading on the topic of grazing and why old-school thinking in regards to cattle ranching must change, check out
Revolution on the Range: The Rise of a New Ranch in the American West by Courtney White

The following two articles were graciously granted permission for republishing from Bill Whitney of the Prairie Plains Resource Institute.  “Why Graze?” appeared in the April 2008 Prairie Plains Link, a newsletter of PPRI, and “Why Burn?” appeared in the April 2007 edition.

Why Graze?

The role of cattle grazing in the management and restoration of native prairie is often misunderstood.  This is particularly true when a relatively small prairie area has been set aside as a prairie preserve.  Regardless of the size of a prairie or the economic or cultural importance of livestock, grazing has an important ecological role in management and preservation of native prairie natural diversity.  Grazing can be used to reduce invasive, non-native species such as smooth brome grass and Kentucky bluegrass.  It can increase the abundance of some very desirable non-grass species, such as the legume, leadplant, by preventing the tall grasses from crowding out small young seedlings.  And large mammals re-distribute organic matter and plant nutrients in the ecosystem in the form of urine and dung, much to the benefit of certain other organisms.  When considering the use of grazing as a management tool, one must first define the purposes and goals of the land being managed.

Our goal is to maintain and enhance the native variety of our prairies, so we need to determine the best way to graze each area – or in some cases not to graze.  The Lincoln Creek site and The Leadership Center prairies in Aurora are small, on the edge of town, and have a walking trail running through them.  Thus, they are not good places to have livestock.  We instead burn the prairies regularly to remove the thatch and invigorate new growth.  Smooth brome is a problem on most of our central and eastern Nebraska properties.  On these sites a fairly intensive graze in the early spring, in addition to occasional prescribed burning, can set the brome back and allow native plants to flourish most of the summer.  The number of animals used (relative to the size and plant composition of each site), the length of time the cattle are on the site and the time of year the graze takes place are all important considerations.  The same number of cattle will create very different effects in different seasons or on a small area versus a large area.  The impact of grazing any site must be closely monitored and evaluated based on the goals established for the land.  This is as true for the rancher whose livelihood depends on sustaining the best grasses as for the naturalist who values the variety of plant life or birds.

There are two other choices for prairie management.  Cutting hay annually or in a rotation system where an area is cut every other year, for example, is not desirable on many prairies since it encourages brome, redtop and bluegrass. Haying has been responsible for protecting the plant community of many eastern prairie remnants, but over time it may not be sustainable. Burning is the other option, but this by itself can create another dilemma for managers. When only burned on a two- to five-year schedule, for example, a tall or mixed grass prairie in Nebraska will develop heavy thatch, which may benefit some wildlife and plants, but will overall negatively impact the prairie by favoring one group or species – the tall stature and most aggressive plants like grasses and sunflowers. Burning frequently – every year or every other year, tends to discourage or even harm some insect and wildlife species.

The point is that any management that is repetitive on a prairie tends to favor a certain group of organisms. The best thing for central and eastern Nebraska prairies is to have a grazing program tied to a regular burning program that meets the goals of the land. And the more random these management tools are applied, the more variety of plant and animal species will coexist and, we hope, thrive in the absence of invasive weeds like musk thistles or brome. Certainly, without a fundamental understanding of prairie (range) ecology – including knowledge of plants, appropriate numbers of livestock and timing – grazing can lead to an increase in invasive species such as leafy spurge (a management nightmare), musk thistle, Canada thistle and smooth brome. It can eliminate rare and more desirable prairie species and increase many common and less desirable ones (though not invasive or non-native). Sometimes grazing is employed out of convenience or desire to keep the income up, which may be contrary to the established goals and purposes of the property. Again, goals must be specific, grazing and burning must fit in with the goals, and the effects of all management actions must be evaluated against the goals each year.

Why Burn?

That has to be our most frequently asked question next to “Why do you cut trees (cedars)?” and “Now just what is it that you do?”  For the most part, prairie consists of perennial vegetation – that is, it comes up year after year, sprouting from underground shoots.  Prairie is extremely productive, providing great quantities of forage and cover throughout the growing season. This vegetation dies back at the end of the season, leaving a thick layer of dry thatch. If this dead plant material were left year after year without removal by grazing, mowing, or burning, the prairie would choke itself out and become invaded by woody species.

Fire has a cleansing, rejuvenating effect. As it removes the built up thatch and woody growth and blackens the soil, it increases subsoil temperatures. This stimulates soil microbial activity that increases nutrient availability for prairie plants. Burning also lengthens the growing season for the natives while shortening it for Eurasian weeds.  More native plants flower, produce seed and are more robust when prescribed fire is used in the management plan. Prairie did not just adapt to growing with fire through the centuries; it evolved with fire.

“For the duration of our time on the planet… restoration will be the great task.” – Kenneth Brower

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