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Cheatgrass & Grazing Rangelands By: James A. Young, Charlie D. Clements and Dan N. Harmon

More than a decade ago we attempted to write on this subject and to cover some very important questions concerning the grazing of Nevada rangelands and the increase in the exotic and invasive annual grass, cheatgrass. This is a rewrite of that attempt that is still a major controversy on Nevada rangelands. In 1916 Charles Fleming joined the staff of the Nevada Agricultural Experiment Station as Chief of the Department of Range Management and later became Director of the Experiment Station in 1946. In 1942 Fleming published “Bronco Grass (Bromus tectorum) on Nevada Ranges” with co-authors M. A. Shipley and M. R. Miller. The opening statement of this publication, “Bronco grass (sic Bromus tectorum) has become a permanent source of feed on many of our most important rangelands and it will necessarily have to be taken into consideration in the determination of seasonal use and in making grazing capacity estimates.” In the Experiment Station 1945-1946 Annual Report, Fleming wrote “The presence of annual grasses creates a controversy between livestock men and grazing administrators involving the following question: Do annual grasses indicate overgrazing? Would the annual grasses be largely absent from Nevada ranges if there had been no grazing? Should the carrying capacity of a range predominantly annual be based upon the perennials? Has anyone a practical method by which annuals can be replaced and perennials reestablished in a density which would permit saying that the range had been brought back to its pioneer carrying capacity? Is it reasonable to look at a range and if annuals predominate say the range is overstocked and a reduction in livestock numbers should be made? ... And if the answers are largely negative, will we not then have to live with the annuals and learn to make the most profitable use of them?” FIGURE 1 Fleming was truly a pioneer in range management. Well over a half century Rest rotational grazing increases cheatgrass seed banks and after Fleming posed his questions about grazing cheatgrass, the controversy associated fuels which leads to cheatgrass dominance. continues. The profession of range management has been deeply involved in an imitation of the Roman Emperor Nero, but in this case they “fiddle” while the ranges of the Intermountain Area of North America burn. Let’s examine the point that there was no vegetation the next year except Russian thistle. The Fleming’s contentions concerning cheatgrass as a forage species with the aid of point where range professionals in the public land management and academic sectors often erred, was to assume that grazing management that was proper hindsight and with some foresight. for ranges dominated by native perennial grasses would automatically lead Do Annual Grasses Indicate Overgrazing? To interpret this question, we to a return of such grasses on sites almost exclusively occupied by cheatgrass. must consider both time and the dominance of annual grasses in relation to This applies across the board in grazing management practices, from reduced native perennial grasses. By the time Fleming wrote his contentious article, part stocking numbers, delayed grazing until after seed ripe, to complete rest from of this issue was already answered. R. F. Daubenmire published in his classic grazing. There is a point in the relative abundance of native perennial grasses and paper "Plant Succession Due to Overgrazing in the Agropyron Bunchgrass cheatgrass where native perennial grasses cannot ascend successionally across Prairie of Southeastern Washington," strong evidence that cheatgrass could the cheatgrass threshold. This is especially significant with the application of invade native perennial grass communities that never had been grazed and were rest-rotation grazing where cheatgrass benefits from deferred, no grazing until in excellent ecological condition. Therefore, this contention depends on the after seed ripe, and complete rest from grazing (Figure 1). relative dominance of cheatgrass. Abundance of native perennial grasses and the increasing presence cheatgrass does not mean the site is in poor range condition Would Annual Grasses Largely Be Absent From Nevada Ranges Had There nor is the site being improperly grazed. Conversely, complete cheatgrass Been No Grazing? Once cheatgrass was introduced, it was only a matter of dominance with no native perennial grasses, as a result of past improper grazing, time until virtually all plant communities in the pinyon/ juniper, big and dwarf does not mean the site is currently being improperly grazed. Leave enough litter sagebrush/bunchgrass, and salt desert rangelands of Nevada were invaded by to minimize accelerated erosion and to provide a seedbed suitable for cheatgrass this species. This was an inevitable conclusion, even in the absence of prior germination results in a conditional sustainable grazing resource of cheatgrass. excessive grazing by domestic livestock. The widespread occurrence of excessive, You must be aware that sustainability of grazing cheatgrass stands is always improperly timed, and repeated grazing on Nevada rangelands heightened at risk from invasion of the stands by plants that do not support grazing. This the rate of dispersal and greatly enhanced the post-dispersal dominance of does not mean you cannot excessively over graze cheatgrass. A. C. Hull, Jr., cheatgrass. It is very important to make this distinction, because otherwise it clearly showed in the 1940s it was possible to excessively graze cheatgrass to leads to the false assumption that removing grazing by domestic livestock would  28 FEBRUARY 2019

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