A Comparative Study of Grazed and Ungrazed Canyons of the Wasatch
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A Comparative Study of the Vegetation of Grazed and Ungrazed Canyons of the Wasatch Range, Utah Author(s): Walter P. Cottam and Frederick R. Evans Reviewed work(s): Source: Ecology, Vol. 26, No. 2 (Apr., 1945), pp. 171-181 Published by: Ecological Society of America Stable URL: http://www.jstor.org/stable/1930822 . Accessed: 06/07/2012 08:52 Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at . http://www.jstor.org/page/info/about/policies/terms.jsp . JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. Ecological Society of America is collaborating with JSTOR to digitize, preserve and extend access to Ecology. http://www.jstor.org A COMPARATIVE STUDY OF THE VEGETATION OF GRAZED AND UNGRAZED CANYONS OF THE WASATCH RANGE, UTAH 1 WALTER P. COTTAM AND FREDERICK R. EVANS Universityof Utah, Salt Lake City, Utah INTRODUCTION' CLIMATIC, PHYSIOGRAPHIC, AND GEOLOGIC FEATUREIS The past twodecades have been marked by intensifiedgovernmental efforts in The WVasatchMountains constitute rangerehabilitation. These effortshave the northeasternrim of the Great Basin. been handicapped by lack of definitein- They rise abruptly as an escarpment formationabout the pristine nature of froma desert floorwith an elevation of grazed lands as well as about quantita- 4500 feet up to altitudes of 12,000 feet. tive and qualitative changes whichgraz- The range is deeply dissectedby numer- ing has doubtless induced in the plant ous canyons having a general east-west cover. The meagernessof the historical direction,of which Red Butte and Emi- recordconcerning the vegetation over the grationcaynons are typical. These two vast grazingareas of the West at the time canyons are parallel to each other with of settlement,together with the almost their mouths directlyeast of and adja- totalabsence of preserved primitive areas, cent to Salt Lake City and discharge makes the problemof reconstructingthe their streams westward into Salt Lake originalplant cover difficultthough not Valley. Red Butte Canyon, which lies impossibleto solve. In these problems one mile to the northof EmigrationCan- ecologyfinds both a duty and a privilege yon, drains an area of approximately25 to serve the land-use program. square miles. EmigrationCanyon drains The Wasatch Mountains east of Salt an area ofapproximately 40 square miles. Lake City,Utah, affordedan opportunity It is characteristicof the canyons of to ascertainsome ofthe effectsof nearlya the Wasatch Mountains that the south- centuryof intensive,unregulated grazing facing slopes are less precipitous than and otherhuman influences on the native their north-facingcounterparts. Since vegetationand soil of various elevations the drainage area of Red Butte Canyon and slope exposures. This study was is less and its lengthshorter than those confined to vegetational problems of of Emigration Canyon while both can- Emigration and Red Butte canyons, yons at theirmouths are approximately the same depth,both slopes of Red Butte while the resultsof parallel but indepen- Canyon are in generalsteeper than those dent soil investigationswere reportedby of EmigrationCanyon. Croft et al ('43) of the same and other In soil and geological features these areas of the Wasatch Mountains. Emi- two canyons show importantdifferences. gration and Red Butte canyons were EmigrationCanyon is composed princi- selected forstudy because of theircom- pally of Jurassic limestone while Red parabilityin position,physiography, and Butte Canyon consistsin part of a com- historicaluse. plex mixtureof Triassic shale, sandstone, and limestone. Considering the great 1 Acknowledgmentsare due the Intermountain Forest and Range Experiment Station, Ogden, differencein grazing use, it was sug- Utah, for valuable suggestionsand financialaid gested by Croft,Woodward, and Ander- in the pursuit of this study. son ('43) that the soils of Red Butte 171 172 WALTER P. COTTAM AND FREDERICK R. EVANS Ecology, VTol,26, No. 2 Canyon erode much moreeasily than do title to most of the land in Emigration those of EmigrationCanyon. It is gen- Canyon. However, some of the canyon erallyrecognized also thatsandstone soils is includedin the Wasatch National For- are basically less favorable for plant est, and a fewsections still remainunder growththan are limestonesoils (Hilgard, private ownership. Because the perma- '06). These factswould seem to favora nent stream in Emigration Canyon is moreabundant vegetationin Emigration small and uncertain, the water is not Canyon and are importantin the analysis used by Salt Lake City fordomestic pur- of vegetationin this paper. poses, and littleattention has been given The Wasatch front, because of its to grazing or erosion problems. City westernexposure and its abruptrise from propertyis still leased to private stock- the desert, is considerably more xeric men, and grazing in this canyon, there- than the canyons that dissect it. Pre- fore, has continued without regulation cipitation,which averages 16.13 inches since the time of settlement. annually at Salt Lake City, increases In addition to the grazing abuses al- with elevation to a maximumof about ready recounted,Emigration Canyon for 40 inches at 9000 feet. The growing a distance of six miles is used as a stock season shortens with higher altitude; trail to and from the higher summer Salt Lake Valley has a frostlessperiod of rangesof the Wasatch and Uintah Moun- about 160 days while BrightonCanyon, tains. The number of sheep passing 10 miles south of Emigration Canyon, over this trail varies fromyear to year. with an elevation of 8700 feet, has an In the springof 1935,for example, 97,550 average growingseason of about 90 days. sheep and 200 cattle used thistrail; in the fall of the same year 123,000sheep were HISTORY OF RANGE USE ANDOWNERSHIP herded down the canyon. By compari- son, the spring drive of 1931 included Soon afterthe settlementof Salt Lake 145,510sheep, and the fall flockstotaled Valley in 1847,both Red Butte and Emi- 209,203 sheep. Trailing here is said to grationcanyons came underprivate own- have begun in the early "fifties." Each ershipand both were utilizedfor grazing flockhas the freedomof the canyonup to purposes. In 1888 the United States the six-milepoint where the trail passes governmentbegan the purchase of Red Butte Canyon for the purpose of estab- over Little Mountain into Parley's Can- lishingFort Douglas at its mouth,and by yon. It is not uncommonfor a single 1909 had acquired title to the entirewa- flockto remaina week withinthe lower tershed. Protectionfrom grazing prob- reaches of EmigrationCanyon. ably commencedwith the firstpurchase Many summerhomes with theirasso- of the land. Even then,however, gully ciated fenced enclosures are located in erosionwas manifestin the canyon. It Emigration Canyon along the stream is assumed that depletion of the plant course, and the canyon is much used for coverwas responsiblebecause, underpro- campingand generalsummer recreation. tection,gullies have become revegetated On the other hand, civilians have been and severeerosion at presentis only half rigidlyexcluded from Red Butte Canyon that foundin EmigrationCanyon. Ring since the turnof this century. counts fromtrees growingon these old Fires at the mouths of both canyons erosionscars place theirage at approxi- are not uncommon. Especially is this mately 40 years, a date which coincides trueof Red Butte Canyon wherevegeta- with the purchaseof Red Butte Canyon tion is purposelyburned to clear the land by the War Department. for target ranges. Both canyons have As a result of a policy to protect its sufferedfrom inadvertent burns at vari- watershed,Salt Lake City has acquired ous places and timesat higherelevations. April, 1945 CANYON VEGETATION OF WASATCH RANGE, UTAH 173 EARLY DESCRIPTIONS OF VEGETATION was compelledto return." (Quoted from Linn, '02.) Clayton ('21), in describing No recordsare extant whichrefer par- the pioneer trek down EmigrationCan- ticularlyto the vegetationof Red Butte yon, said, "The grass on the creekgrows Canyon, and but fewrefer to the vegeta- fromsix to twelve feethigh and appears tion of Emigration Canyon in 1847. veryrank." (Doubtless Elymusconden- However, it is significantthat available satus.2) At theirlast encampment,a po- referencesdescribe Emigration Canyon sition six miles fromthe mouth of this as denselyvegetated. William Clayton canyon, he wrote, "The grass here ap- ('21), an early Mormon historian,stated pears even thickeron the ground than that it was necessary, because of the where we left this morning. The soil dense growthof vegetation,for the pio- looks indeed rich, black and a little neersto reconstructa road throughEmi- sandy. The grass is about fourfeet high gration Canyon which had apparently and very thick on the ground and well been used by the Donner party only the mixedwith rushes." At the presenttime year previous. In July, 1847, Erastus the vegetationin EmigrationCanyon has Snow and Orson Pratt traveled through no such appearance,but, in general,these Emigration Canyon in advance of the main pioneer party. Snow said that 2 Authorityfor plant names is Tidestrom,Flora "The thicketdown the narrows at the of Utah and Nevada, with the followingexcep- mouth of the canyon was so dense that tions: grasses,