Red Butte Canyon Research Natural Area: history, flora, geology, climate, and ecology

Red Butte Canyon is a protected, near pristine canyon entering Salt Lake Valley, Utah. It contains a well-developed riparian zone and a perennial stream; hillside vegetation ranges from grasslands on the lower limits to Douglas-fir and aspen stands at the upper elevations. In this paper we describe the history of human impact, natural history aspects of climate, geology, and ecology, and faunal and floral information for key species in the canyon. The role and importance of Research Natural Areas is discussed, particularly with respect tathe need to protect Red Butte Canyon---one of the few remaining undisturbed riparian ecosystems in the Intermountain West.

The Great Basin Naturalist Published at Provo, Utah, by Brigham Young University ISSN 0017-3614 Volume 52 June 1992 No. 2 Great Basin Naturalist52(2), pp, 95-121 RED BUTTE CANYON RESEARCH NATURAL AREA: HISTORY, FLORA, GEOLOGY, CLIMATE, AND ECOLOGY James R. Ehleringer , Lais A. AnKw, Ted Aroow, Irving B. McNulty , and Norman C. Negus Abstract - Red Butte Canyon is a protected near pristine canyon entering Salt Lake Valiev. Utah It contains a well-developed riparian zone and a perennial stream; hillside vegetation ranges from grasslands on the lower limits to Douglas-fir and aspen stands at the upper elevations In this paper we describe the history of human impact, natural history aspects of climate, geology, and ecology and fauna! and floral information for key species in the canyon. The role and importance of Research Natu ral Areas is discussed, particularly with respect to the need to protect Red Butte Canyon-one of the few remaining undisturbed riparian ecosystems in the Intermountain West. Key wordsi grassland, IntvrmoHntain West, oak-maple, plant adaptationr Red Butte Canyon, Research Natural Area, riparian ecology. Red Butte Canyon, one of many canyons in the Wasatch Range of Utah, opens westward into Salt Lake Valley, immediately east of the University of Utah (Fig. 1). Like most canyons along the Wasatch Front, it is a grassland at the lowest elevations, is forested at its upper end, and has a perennial stream. What makes this canyon u nusual is its history. The canyon was the watershed for Fort Douglas, the U.S. Army post built in 1862 that overlooked Salt Lake City. As a protected watershed, these lands were, for the most part, kept free from grazing, farming, and other human-impact activities. When the U.S. Army declared these lands surplus in 1969, the U.S. Forest Service assumed responsibility for the canvon. Since that time. Red Butte Can von J J has been kept in its protected state and desig­nated a Research Natural Area (RNA). The Research Natural Area designation denotes an area that has been set aside because it contains unusual or unique features of sub­stantia] value to society. These might include unique geological features, endangered plant and animal species, or areas of particular value for scientific research as baseline bench marks of ecosystems that have been largely destroyed by human impact. In the case of Red Butte Canyon, the RNA designation was given because this canyon is one of the few remaining (if not the last) undisturbed watersheds in the Great Basin. The U.S. Forest Service report proposing that Red Butte Canyon be declared a Research Natural Area described ihe canyon as . a living museum and biological librarv of a size that exists nowhere else in the Great Basin . . . an invaluable bench mark in ecological time." The Red Butte Canyon RNA is unique because it is a relatively undisturbed watershed adjacent to a major metropolitan area (Salt Lake Valley). To protect this valuable resource, access to the Red Butte Canyon RNA has been largely restricted to scientific investigators. One of the96 G reat Basin N aturalist [Volume 52 Salt Lake City'////////// Intl. Airport 0 c mile kilometers ////////// '//>///// //*/ w/s/s/sr/// f/f/ff/SJf/'fS, rs // // i<y //// « University sssssss ssssss ssswss, /////A Sss/ss. fsjfjs, s/jsss* ffst/fffh Salt Lake City "SSSSfSSSSfSSSSSSf ‘ J fjf/j fs/sss. yv /v /y/ /// fssjsss /// ///z> /////////j' ////V JsSSS/SJ/SSfSSSA/SSffSSSfffSSS/SSfJ-SjrssSfSsS fftf. Pinecrest 555 $ $ % rr <8 ///////■ «/y/y/ Mitt C^eek Cnyn Fig. 1, Location of Red Butte Canyon and oHier sites referred to in text, goals of the RNA Program is to protect and preserve a representative array of all significant natural ecosystems and their inherent processes as baseline areas. A second goal is to conduct research on ecological processes in these areas to learn more about the functioning of natural versus manipulated or disturbed ecosystems. Research activities in the Red Butte Canyon RNA are directed at both of these goals: under* standing basic ecological processes (physiologi­cal adaptation, drought adaptation, nutrient cycling, etc.) and also the impact of humans on our canyons through both airborne (air pollu­tion, acid rain, etc.) and land-related (grazing, human traffic, etc.) activities. The latter are conducted through comparison of Red Butte with other canyons along the Wasatch Range. In size, Red Butte Canyon is relatively small compared with other drainages along the, Wasatch Front. The drainage basin covers an area of approximately 20.8 km2 (5140 acres) (Fig. 2). The drainage arises on the east from a minor divide between City Creek and Emigra­tion canyons and drains to the west. The canyon lias two main forks (Knowltons and Parleys) and many side canyons. Near the canyon base, a reservoir was constructed earlier this century to provide a more stable water supply to Fort Douglas. The diversity of slope and aspect com­binations of the terrain contributes to a variety of biotic communities along an elevation gradi­ent from about 1530 m (5020 ft) on the west end to more than 2510 in (8235 ft) at the crest. The purpose of this paper is to provide a brief description of the his tor)-; flora, geology, cli­mate, and ecology of diis unusual and valuable resource. There is increasing interest in Red Butte Canyon, in part by scientific investigators because of its utility as a protected, undisturbed watershed, anti in part by curious citizens from the nearby Salt Lake Valley. Yet. there Inis not been an overall reference available for those interested in general features of the canyon or past ecological studies within the canyon. Most of the information on Red Butte Canyon is scattered. With the closure of Fort Douglas in 1991, many of the historical records will become more difficult to access. It is hoped that the synthesis presented in this paper will provide the necessary background for those interested in the history and ecology of the Red Butte Canyon RNA. Irving McNulty first summarizes the history of the canyon, followed by Ted Amows description of geology and soils, James Ehleringer contributed the hydrology, climate, and plant ecology sections. The section on vas­cular flora was prepared by Lois A mow, and Norman Negus wrote the mammalian and avian fauna sections.1992] Re d B u t t e Canyon R e s ea r c h N atural Area 99 Table I. Description of geological formations in Red Butte Canyon, 1 ............. ■ ■ i ■■ ■ I. - ■ ■■ k m . II ■ a. ftllMlI II, II, I i ■■ ................. fcl *j, . Cenozoic- era, Quaternary' system, Holocene series fa Fhod-phin alhmwm. Sand, cobbly to silty, dark gray at top; grading downward to medium to light gray, sandy to cobbly gravel; locally bouideiy. fe Engime/'ed fill Selected earth material that has been emplaced and compacted, Cenozoic era, Quaternary and Tertiary systems, Holocene and Pleistocene series fg Alluvial-fan deposits. Bouldery to clayey silt, dark gray to brown; rocks angular to subrounded. Id landslide deposits. Composition similar to material up slope. Mesozoic era, Jurassic system Jtc Ttuin Creek Limestone. Brownish gray and pale gray to pale yellowish gray silty limestone, intercalated with greenish gray shale. Mesozoic era, Jurassic? and Driassic? systems JTn Nugget Sandstone. Pale pinkish buff, fine- to medium- grained, well-sorted sandstone that weathers orange- brown. Massive outcrops form the ridge called Hed Butte. Mesozoic era, Triassic system Tau Ankareh Formation, upper member. Reddish brown, reddish purple, grayish red, or bright red shale, siltstone, and sandstone. Tag Ankareh Formation, Gattra Grit Member. White to pale puiple, thick-bedded, crossbedded, pebbly quartzite. Forms a prominent white ledge for lon$ distances. Tam Ankat'eh Formation, Mahogany Member, Reddish brown, reddish purple, grayish red, or bright red shale, siltstone, and sandstone. Tt Thaunes Formation. Medium to light gray, fossiliferous, locafly nodular limestone., limy siltstone, and sandstone, Tiv Woodside Shale. Grayish red, grayish purple, or bright red shale and siltstone. Paleozoic era, Permian system . Ppc Park City Formation and related strata- Fossiliferous sandy limestone, calcareous sandstone, and a medial phosphatic shale tongue. Paleozoic era, Pennsylvanian system Pw Webei' Quartzite. Pale tan to nearly white, fine- to medium-grained, crossbedded quartzite and medium gray to pale gray limestone. Pro Round Valley Limestone. Pale gray limestone with pale ;ray siltstone partings. Contains pale pinkish chert that forms irregular nodules. Paleozoic era, Mississippian system Mdo Doughnut Formation. Medium gray, thin-bedded limestone with pods of dark gray to black chert and abundant brachiopods and bryozoa. Mgb Great Blue Forination. Thick-bedded, locally cliff- forming, pale gray, fine-grained limestone. Mh Humbug Formation. Alternating, tan-weathering, limy sandstone and limestone or dolomite. Md Deseret Limestone. Thick ledges of dolomite and lime­stone with moderately abundant lenses and pods of dark chert. Paleozoic era P Paleozoic rocks, undifferentiated, protect the water supply of Fort Douglas. This law preven ted any sale of land in the canyon or further watershed development. In 1906 the U.S. Army built a dam on Red Butte Creek to supply additional water for Fort Douglas. The present dam was constructed between 1928 and 1930, and the reservoir provided water for Fort Douglas until its closure in 199L There are no grazing records available for Red Butte Canyon prior to 1909, by which time the U nited States had acquired title to most of the land in the canyon, Cottam and Evans (1945) reported evidence of some gully erosion occurring in the canyon prior to 1909 and assumed it was due to overgrazing. Although we lack quantitative data, there are a few isolated incidents indicating the occurrence of grazing, i ncluding an 1S54 report of a young man drown­ing in a flash flood in Red Butte Canyon while herding animals. Over fort)' head of oxen used to haul sandstone from the quarry in the iate 1800s remained in the canyon during that time. In 1869 the War Department appointed a herder to control loose cattle grazing on Fort Douglas and in the canyon. In 1890 three squat­ters had settled into the canyon., and their forty head of cattle were grazing in the Parleys Fork area before being evicted. By 1909 the Army had built a gate at the mouth of the canyon to control access, thus further protecting the watershed. Although this did not prevent occa­sional animals from wandering into the canyon from adjacent canyons, it did reduce both their numbers and their length of stay. Consequently, most of the canyon has not been grazed by cattle or sheep through most of this century. Portions of the upper reaches of the canyon were timbered In 1848, when a road was built along the canyon bottom, it was repotted that there was an abundance of timber suitable for fence poles. Later The Church of Jesus Christ of Latter-day Saints built a bowery on. Temple Square in downtown Salt Lake City in. the 1850s with wood obtained from Table Mound (between Knowltons Fork and Beaver Canyon). In 1863 the Army constructed 34 buildings at Fort Douglas from ‘‘timber hauled from the canyons/' but there is no indication as to how much timber came from Red Butte Canyon. However, apparently not many timber-size trees were available in the lower canyon as indicated by a pioneer who built a log cabin in the canyon. He stated he had to travel five miles up the100 G reat Basin Naturalist [Volume 52 canyon to obtain enough logs for tlie cabin in the early 1860s. There are no available records oi fires that may have occurred in the canyon, In 1988 a fire from Emigration Canyon spread into the upper headwaters of Red Butte Creek before it was contained. The land was subsequently reseeded with native species by the U.S. Forest Service. Land ownership within the canyon changed several times during the late 1800s and early 1900s. Land occupied by Fort Douglas in 1862 was officially given to the U.S. Army in 1867 when President Johnson withdrew four square miles from public domain for the use of the Army. However, this included only a small por­tion of the mouth of Red Butte Canyon, The Salt Lake Rock Company, which quarried most of the sandstone in the canyon, owned part of the canyon, and the Union Pacific Railroad Co. acquired four sections in the lower portions of the canyon in the lS60s, Smaller portions of the canyon were claimed by private individuals under the Homestead Act of 1862. Such claims could be acquired easily under this act, which was very liberal and required only a small claim fee. Gradually, between 1884 and 1909, through a combination of acts of Congress, exchanges of property, and outright purchases, Fort Douglas obtained title to most of the canyon, by 1896 and almost the entire canyon by 1909, Only three small parcels of a total oi less than 90 hectares (-200 acres) are still privately owned today, and these are close to the margins of tlie canyon. In 1969 the U.S. Department of Defense relin­quished ownership of Red Butte Canyon. The U.S. Forest Service is now responsible for these lands. Tlie Forest Service recognized tlie natu­ral state of the area had been preserved through many years of closure to the public and desig­nated Red Butte Canyon a Research Natural Area in 1970. By definition such areas are tracts of land that have not been strongly impacted by human-related activities such as logging or graz­ing by domestic livestock. They are permanently protected from devastation by humans so they may serve as reference areas for research and education. Red Butte Canyon has served as a research site for biologists for over fifty years and will continue to do so in the future. Public education about conservation and the need for the public to better understand the importance of Research Natural Areas are major concerns. Recently the Forest Service briefly opened the canyon to the general public. In 1987 the canyon was opened to the public in late spring for several days; tills weekend opening attracted over 5000 visitors and led to a trampling on vegetation along the main road in the canyon. This opening was repeated in 1988 and attracted 1100 people. Currently the State Arboretum at the University of Utah conducts natural history education classes ( - 10 individu­als per group) in the lower portions of the canyon. Limited deer hunting has been permit­ted by the Forest Service each fall, but the impact of the hunts is unknown. A Red Butte Steering Committee, consisting of representa­tives from the Forest Sendee, the University of Utah, and other government agencies con­cerned with preservation of natural areas, is involved in making decisions pertinent to the jurisdiction and management of the Red Butte Canyon Research N atural Area. The history of Red Butte Canyon., with the exception of the quarrying activity and some grazing in the past century, is largely a history of preservation. The U.S. Army at Fort Douglas was concerned with the protection of the water­shed and gradually acquired sufficient control to protect it. The U .S. Forest Service declared the entire canyon a Research. Natural Area and thus insured its protection for the future as a bench mark of riparian and shrub ecosystems in the Intermountain West. Geology The rocks underlying Red Butte Canyon range in age from recent Holocene deposits of our time; to Mississippian rocks that are about 360 million years old. Holocene and Pleistocene deposits are unconsolidated, consisting mostly of landslides or alluvium deposited by existing streams. Their aerial distribution is shown in Figure 3, and a description of the deposits is given in Table J.. . The older rocks range in age from Mississippian to Jurassic, a span of about 220 million years. They are all consolidated now, but originally they were formed as deposits in oceans or inland seas or as sand dunes in an arid environment. No rocks representing the approximately 140 million years between the end of Jurassic time and the Holocene are pres­ent in Red Butte Canyon. Either they were never deposited or they have been eroded. The consolidated rocks in most parts of theG reat Basin N aturalist [Volume 52 Township IN. Range IE seel ion 2 kilometers Fig. 5, Soils map of Red Butte Canyon. See Table 2 for a description of abbreviations. Adapted from Woodward et a], (1974), until flow is collected in the reservoir located near the base of the canyon. The stream has created a narrow-based canyon with sides rising abruptly at an average slope of about 35 degrees to the north and about 40 degrees to the south. Immediately upstream of the reservoir is a U.S. Geological Survey Hydrologic Bench Mark Sta­tion. This gaging station has been maintained by the U.S. Geological Survey since October .1963, Prior to that, the Corps of Engineers, U.S. Army, recorded monthly discharge at this location beginning in January 1942. The average monthly discharge (1964-88) is 0.133 m'Vsec (-4.7 ft3/sec) as it enters the res­ervoir at 1646 in (5400 ft) elevation (U.S. Geo­logical Survey records). The stream flow exhibits a straightforward annual pattern, char­acteristic of this geographic region-high spring flows driven by snowmelt followed by very much reduced flows derived from groundwater throughout the remainder of the year (Fig. 6). Spring melt flow, which is typically an order of magnitude greater than other periods of the year, peaks in May and persists for 6-8 weeks. The average monthly stream flow rate during May is 0.416 m'Vsec (14.7 ft'Vsec), By Septem­ber, the lowest average mondily flow rate, stream discharge has decreased to 0.058 m3/sec (2.0 ftVsec). Mean, stream flow rates do not increase during the summer months, although nearly one-fourth of the annual precipitation falls during this period. Average monthly stream flow values, how­ever, hide much of the stream dynamics and resultant impact on riparian vegetation. On a daily basis, stream flows can vary tremendously1.992] R e d B u t t e C anyon R e sea r ch Natural Area 103 Table 2. Description of unifcs on the soils map of Red Butte Canyon. AGG Agassiz- association, very steep. 40-70 percent slopes; moderately permeable, well drained. Agassiz-35 percent, very cobbly silt loam on ridges and convex areas of upper slopes. Picayune--55 percent, noncalcareous variant, gravelly loam in concave areas and in draws. Other soils-10 percent. BCG Brad very rocky loamy sand, 40 to SO percent slopes. Very permeable, extremely well drained. Very rocky, cobbly, loamy sand; dark reddish-brown; shallow. BEG Braclshaw-Agassfe association, steep. 40-70 per­cent slopes; moderately permeable, well drained. Bradshaw-55 percent, very cobbly siltdoam in slightly concave areas. Agassis.-35 percent, very cobbly sitf-loain in convex areas and ridgetops where soil is shallow. Other soils-10 percent. DGG Deer Creek-Picayune association, steep. 30-60 percent slopes; moderately permeable, well drained. Deer Creek-55 percent; loam; very dark brown; deep on very steep, north- and northeast-facing mountain slopes. Picayune-35 percent; gravelly day loam; very dark brown, deep, calcareous on west-facing slopes. Other soils-10 percent. EMG Emigration very cobbly loam, 40 to 70 percent slopes. Moderately permeable, well drained. Cobbly Joarn; facing south; dar k, grayish brown; shallow; patches of bedrock. HGG Harkers-Wallsburg association, steep. Moder­ately permeable, well drained. Harkers-55 percent, loam, 6-40 percent slopes, very dark brown, deep in drainageways and concave areas of slope faces. Walls- burg -35 percent, very cobbly loam, 30-70 percent slopes, on ridges and convex areas of slopes where bed­rock is near the surface, very dark grayish brown, shallow. Other soils-.10 percent. HHF Ilarkere soils, 6 to 40 percent slopes. Moderately permeable, well drained. Loam and cobbly loam, on sloping old alluvial fans and steep mountain slopes. LSC Lucky Star gravelly loam, 40 to 60 percent slopes. Moderately permeable, well drained. Very dark grayish brown, deep on northerly slpes, Mw Mixed alluvial land. Poorly drained, highly stratified mixed alluvium on undulating, gently sloping, and nearly level flood plains. during snowinelt, depending on air tempera­tures and snowpack depth, (primarily that of upper Red Butte Canyon and Knowltons Fork) . The 19S2-S3 winter was one of unusually high precipitation along the Wasatch Front. Heavy snows in mid-May 1983 were followed by equally unusual warm temperatures at the end of the month. As a consequence, stream flow rates peaked at record values. On 28 May 1983, Red Butte Creek crested at a discharge rate exceeding 2.97 rn'Vsec (104,9 itVsec) (stream flow was above the maximum gage height), and overland flow was substantial. This was by far the greatest discharge rate in recent times, having eclipsed the previous maximum single day rate of 1.70 m3/sec (60.0 ft "/sec) measured on 18 May 1975 (U.S. Geological Survey Records). The unusually high stream discharge rate in May 1983 is of particular significance because of its impact on stream geomorphology and adjacent vegetation. Tlie high, flows quickly scoured the streambed, taking out beaver dams, eroding stream banks, knocking down riparian trees, and causing massive erosion. Gullies 5-10 m (16-33 ft) deep were cut into permanent streamheds in Knowltons Fork and throughout Red Butte Creek. Sediment flow associated with tins record stream discharge was in excess of 269 metric tons ( -"593,000 lbs) per day in mid-May (compared to typical spring melt con­centrations of 1 metric ton 1-2200 lbs] per day) (U.S. Geological Survey Records); this resulted in a delta formation at the mouth of Red Butte Reservoir. Prior to the 1982-83 winter, no delta had existed. The delta was soon -SO m (~ 100 ft) long. By 1990 the delta had fanned out more than 60 m into the reservoir. The heavy winter rains of 1982- 83 saturated soils all along the Wasatch Front, and landslides were common. Red Butte Canyon was no exception. Slope sloughing, which, killed the overlying perennial, vegetation, was common throughout tlie canyon, No doubt this compounded the stream sedi­ment load during the spring of 1983 and for several years thereafter. In 1990 signs of the 1982-83 slope sloughing were still clearly obvi­ous in Knowltons Fork as well as in the upper and. lower portions of the main canyon. Natural revegetation of both riparian and slope vegeta­tion types has occurred since these floods. In particular, Acer negundo (boxelder) and Salix exigu-a (willow) have increased in frequency in the newly deposited alluvium along the stream- sides (Donovan and Ehleringer 1,991). Recov­ery of the sloughed slopes, which were for the most part covered by A. grandidentatum (bigtooth maple) and Quercus gambelii (Gambel oak), has proceeded at a slower rate, with those slopes still dominated by herbaceous species. As part of the bench mark analysis, the U.S. Geological Survey monitors several major aspects of stream quality in addition to stream discharge, including water temperature, suspended sedi­ment, and chemical quality. Included with chemical quality are specific conductance, pH,104 G reat Basin Naturalist [Volume 52 CO co £ <D Q) s- cd J= o p © C/5 1.50 1.25 ' 1.00 ~ 0,75 0.50 - 0.25 - 0 \9 % % % % *%> Fig. 6 Mean monthly discharge rates of Red Butte Creek just before it enters Red Butte Reservoir, Large and small tick marks indicate end-of-year and inid-year points, respectively. Data are from U.S. Geological Survey records, dissolved oxygen concentration, coliform bacte­ria, and ionic and dissolved elemental concen­trations (ammonium, arsenic, beryllium, cadmium, calcium, carbonate, chloride, chromium, cobalt, copper, fluoride, iron, lead, lithium, magnesium, manganese, mercury; molybdenum, nickel, nitrate, nitrite, phosphate, potassium, selenium, silver, sodium, sulfate, strontium, vanadium, and zinc). The stream itself is strongly alkaline (pH S .0-8.6), and travertine is deposited at sev­eral points along the stream channel (Bond 1979). Summertime stream flow represents groundwater discharge, while the spring flows result primarily from snowmelt at higher eleva­tions. Not all of the groundwater originating from upper-elevation sources enters the stream before it leaves the canyon. Tracing the possible sources of water into stream, and therefore that water which is available to plants, is possible by analyzi ng the isotopic composition of that water. The deuterium :( II or D) to hydrogen (!TI) ratios of stream waters have been measured since June 1988 at the USGS Bench Mark sta­tion and at the mouth of Parleys Fork by the Stable Isotope Ratio Facility for Environmental Research at the University of Utah (Dawson and Ehleringer 1991). These naturally occurring stable isotopes of hydrogen provide long-term data that are useful in addressing both long­term regional climatic patterns and the specific water sources used by plants for growth (see discussion below). Hydrogen isotope ratios (ratio of D/H of a sample to that of a standard) are measured relative to an ocean water stan­dard; samples lighter than ocean water have less deuterium and are therefore negative in their values. Over the four-year measurement period (1988-91), hydrogen isotope ratios of stream waters have averaged near -122%<?, with the only seasonal changes being more negative values occurring during spring snowmelt. Typi­cally the hydrogen isotope ratio of winter storm events (snow) is more negative than that of summer storms, The hydrogen isotope ratios of wells and springs near Pinecrest (immediately east of Red Butte Canyon) are - 132%C', slightly more negative than Red Butte Creek (Dawson and Ehleringer 199.1), and suggest that a frac­tion of the groundwater originating from the upper portions of the canyon may persist as underflow and does not enter the creek before leaving the watershed. Hely et al. (1971) indi­cated that substantial fracturing occurs in the bedrock of Red Butte Canyon, which would have the effect of increasing groundwater loss from the canyon through these layers and not via stream discharge. Bond (.1977, 1979) investigated nutrient- con centration patterns of stream flow in Red Butte Creek. In particular, his studies focused1992] Re d B u t t e Canyon R e sea r ch N atural Area 105 Table .3. Locations oi weather stations of Red Rutte Canyon, All stations were operated by the U.S. Army between 1942 and 1964, and only precipitation was recorded. The. U.S. Geological Survey has maintained a storage gage at Red Butte #2 since 1964. The Biology Department at the University of Utah lias maintained daily temperature, humidity, and wind speed records at Red Butte #2, Red Butte #4, and Red Butte #6 since 1982. Red Butte #1, while technically outside the canyon, iorrns an integrated part of the weather station complex. Station Location Latitude Longitude Eievation Period Red Butte #1 Fort Douglas 40® 46' 110° .50' 1497 m 1942-1964 Relocated to Biology Experimental Carden 40° 46' 110°50' 1515 m 1991-present Red Butte #2 Head of Red Bntte Reservoir 40"47' nr 48' 1653 m 1942-1964 1982-present Red Butte #3 Along Red Butte Creek at Brush .Basin 40" 48' nr 47- 1865 m 1942-1952 Red Butte #4 Along Red Butte Creek 100 m west of Beaver Canyon 40° 48' nr 46' 1890 in 1942-1971 1982-present Red Butte #5 Parleys Fork 100 m above inlet to Red Butte Creek 40° 47' 111*48' 1753 m 1942-1956 Red Butte #6 U pper end K nowitons F ork; 40* 49' nr 45' 2195 m 1946-1971 relocated to top of Ells Fork 40° 49f in°46' 2195 m 1982-present on relationships between nutrient transport out of the watershed and stream discharge rates. Solute concentration was not necessarily pro­portional to stream discharge. Instead, for many ions, such as magnesium, sulfate, and chloride, the relationship was logarithmic. The slopes of these relationships depend on whether stream How is increasing (i.e., spring snowmelt) or decreasing, Over the course of the year, a loop or directional trajectory was formed by having two different slopes. For most of the major ions, the trajectory was clockwise; that is, ionic con­centration wa s greater in winter when flow rates were low than during summer. Plant growth of the dominant riparian species commences near the end of the snowmelt period, and it is ques­tionable whether riparian species are able to utilize the greater nutrient availability during the snowmelt period. After snowmelt, stream discharge is based primarily on groundwater input. Nitrate, ammonium, and phosphate con­centrations in Red Butte Creek during ground­water discharge are low (Bond 1979). In contrast, overall concentrations of calcium, magnesium, sodium, chloride, and sulfate are much greater because of parent bedrock char­acteristics. Climate Climate within Red Butte Canyon is charac­terized by hot, dry summers and long, cold winters. Most precipitation occurs in winter and spring, with the summer rains less predictable and dependent on the extent to which rnon- soonal systems penetrate into northern Utah. Mean annual precipitation ranges from about 500 mm (20 in) at the lower elevation to approx­imately 900 mtn (35 in) at the higher elevations (Hely et al 1971, Bond 1977; Table 3). Precipitation stations have been monitored in Bed Butte Canyon by several groups. The U.S. Army had six rain gages in operation between 1942 and 1964 (Table 3). Bond (1977) collected data at several of these stations between 1972 and 1974, In addition, the U.S. Geological Survey maintained storage gages at Red Butte #2, Red Butte #4, and Red Butte #6 between 1964 and 1974. Since that time, they have maintained a storage gage at Red Butte #2. Within the watershed, daily precipitation as rainfall is collected at each of the weather sta­tions: snowfall is not adequately measured by the sensors in place. However, these data are currently collected at Hogle Zoo in Salt Lake City (same elevation as previous Red Butte #1, but 4 km south). Variation in annual precipitation within Red Butte Canyon is strongly dependent on eleva­tion (Fig. 7). The slope of this relationship is similar to that observed for other mountainous areas within the Great Basin (Houghton 1969), and precipitation at. the Salt Lake City reporting station ( Salt Lake City International Airport) falls on this relationship. Thus, while lacking continuous precipitation records (or the canyon proper, precipitation records available for Salt Lake City can be used as a preliminary basis for estimating mean annual precipitation at differ­ent locations within the canyon.106 G reat Basin N aturalist [Volume 52 e E C. a ‘SL 0 £ G. 2 n c 1 Elevation, rn Fig, 7- Relationship between mean Bfinu&i precipitation and ejevation for Red. Butte Canyon storage gages Red Butte #l-#6, Shown also is the mean annua), precipitation for the primary station of Salt Lake City (Salt Lake City International Airport) as the open symbol 30 - io pd o L * c a? 20 - P <0 br 0 ty 1 £ 10 Fig. 9. Mean monthly maximum and minimum air tem­perature at Red Butte #2 {.1653 m elevation), Red Butte #4 (1890 m elevation), and Red Butte #6 (2195 m elevation) during the growing season between 1982 and 1990. Air temperatures have been collected trom automated weather stations at Red Butte #2, Red Butte #4, and Red Butte #6 since 1982. Mean monthly air temperatures at Red Butte #2 were below freezing in December and January and above 20 C in June, july, and August (Fig. S). In contrast, mean monthly temperatures at Red Butte #6 were below freezing only slightly longer, from November through February, and above 20 C in July and August. During the main growing period {May through September), day­time maximum temperatures ranged between Pig, 8. Mean monthly air temperature, vapor pressure, and photosynthetically active solar radiation (400-700 nm) measured at Red Butte #2 between 1982 and 1990. 18.7 and 31.8 C (66--S9 F) at Red Butte #2, while nighttime minimum temperatures ranged between 5.2 and 16.4 C (41-62 F) {Fig. 9). At the higher-elevalion stations, daytime maximum air temperatures were lower. The difference in maximum temperatures was negatively related to elevation (maximum temperature [°C] - 34.3 - 0.00494 ■ elevation jm], r = .91) at approxi­mately half the dry adiabatic lapse rate. On the other hand, nighttime minimum temperatures were not related to elevation, because of cool- air drainage effects (Fig. 9), Red Butte #4 is located streamside within the canyon, whereas the other two stations are above the channel of cold air that develops at higher elevations and pours down the canyon at night. As seen in Figure 9, this cold-air drainage effect at Red Butte #4 (1890 m [6180 ft] elevation) depressed nighttime minimum air temperatures by 4-8 C (7-14 F) below that observed at Red Butte #6 (2230 m 17292 ft j elevation). Photosynthetically active solar radiation (PAR, 400-700 nm), atmospheric vapor pressure,1992] Re d Bu t t e C anyon R e sea r ch N atural Area 107 and wind speed are also recorded at each of these stations. Between 1982 and 1990, mean daily total PAR values have exceeded 40 mo) m "d"1 (Fig. S), which is typical for mid-latitude sites having only moderate cloud cover and little summer precipitation. This number is quite useful not only in estimating the available photon flux for photosynthesis, but also in pro­viding an estimate of the exten t of solar heating of the surface, which ultimately affects air tem­peratures. Elevation has a limited impact on the PAR values within Red Butte Canyon, since the difference in elevation is relatively small. How­ever, we suspect there may be relatively large differences in PAR between Red Butte Canyon and Salt Lake City because of increased air pollutants within the city that tend to reflect the sunlight before it strikes the earths surface. Most notably we would see this as haze or smog within the valley that is lacking once in. the canyon. Average monthly atmospheric vapor pres­sure at site #2 showed little annual variation, ranging only about 3 mbar throughout the year (Fig. 8). Other sites exhibited a similar pattern. This parameter is largely affected by large air mass movements; and since subtropical air masses do not move into this region during the summer, the monthly changes in atmospheric vapor pressure change little during the course of the year. However, because of the large annual change in air temperature and the non­linear dependence oi the evaporative gradient on temperature, relative humidity levels are substantially lower and evaporative gradients are substantially higher during the summer months. Vascular Flora From the mouth ol Red Butte Canyon at about 1530 m (5020 ft), its walls rise to their highest point--2510 m (8235 ft)-at the head of Know! tons Fork in the northeast corner of the canyon. Within this modest rise of980 m (32-15 ft) occur four distinct plant communities: ripar­ian, grass-forb, oak-maple, and coniferous. Pinon-juniper and ponderosa pine communi­ties, which often occur in this elevationaJ range in Utah (Daubenmire 1943), are not present in Red Butte Canyon. Billings (1951, 1990), in discussions of vegetational zonation in the Great Basin, cites a greater incidence of winter cyclonic storms and slightly more moist sum­mers as factors producing the variation in the vegetative zones of the eastern boundary of the Great Basin, jumper is present in the central Wasatch Range, but only three Utah juniper (juniperus osteospeiyna) are known to exist in Red Butte Canyon: a mature tree with a 0.5 m (1.6 ft) diameter trunk, located on the south slope of Parleys Fork and nearly obscured by the more mesophytic vegetation, and two shrublike plants 1-1,3 m (3-4 ft) tall growing on the south­west divide. With few exceptions, notably the naturalized grasses Agrostis stolonifera (redtop bentgrass), Bromus tectonim (cheatgrass), and Poa praten- sis (Kentucky biuegrass), only the most common indigenous plants that occur in the various plant communities are listed below, primarily because the presence of introduced plants is usually dependent on disturbance and tends to fluctu­ate accordingly. Some of the more frequently occurring introduced plants are listed in a sep­arate section. Riparian community.-From, the point at which Red Rutte Creek emerges from the canyon and throughout the floor of the canyon the streamside vegetation (plants residing in soil kept moist to wet by the stream) consists chiefly of western water birch (Betula occidentaiis ) and mountain aider (Alnus incana), accompanied, at inteivals by usually dense stands of red osier dogwood {Cornus sericea) and willow (Salix spp.). Adjoining the stream along the floor of the canyon below and above the reservoir is an often densely wooded strip consisting chiefly of Gambel oak (Quercus garrdmlii), boxelder (Acer negundo), and bigtooth maple (Acer grandi- dentatum), many of these trees ranging from 9 to 18 in {30 to 60 ft) or more talL Also included in this plant community are widely scattered individuals or small populations of cotton woods (.Populus fremontii, P. angustifolia, and P. X acuminata), chokecherry (Primus mrginiana), Woods rose (Rosa toaodm), bearberry honey­suckle (Lonicera involucrata), thimbleberry (Rubus panrifiorus), serviceberry (Amelanchier alnifolia), western black currant (Hibes hud- sonianum), and golden currant (Ribes aureum). Relatively few species of grass and forbs are found here, among them* Ely mus giaucus Lonvitium dissectum Mahonia repens (Berberis repens) Osmorhiza chilerim Poa eompressa blue wildrye giant lomatiuiii Oregon gfape sweet cicely Canada biuegrass108 G reat Basin Naturalist [Volume 52 P. pmtensis SmUacina stellata S, racemasa Solidago oanademis Kentucky bluegrass wild lily-of-tbe-valky false Solomon-seal goldenrod Beaver, once native, were reintroduced into Red Butte Canyon in 1928 (Bates 1963) and were active along Red Butte Creek and some of its tributaries for 54 years thereafter. Numerous marshy areas between elevations of 1645 m (5400 ft) and 2133 m (7000 ft) were created by the impoundment of water due to their darn- building activities. To prevent the beaver popu­lations from becoming undesirably large, the Utah Division of Wildlife Resources in 1971 undertook management of the populations. In December 1981 a recommendation was made, based on an analysis of the water supply to Fort Douglas from Red Butte Canyon, that all beaver be eliminated trom tlie canyon because their feces could contaminate the water with the par­asite Giardia lamblia. Accordingly, in 1982 the colonel in command of Fort Douglas applied for and received from the Utah Division of Wildlife Resources a permit to remove the beaver from the canyon. Subsequently, all beaver were 'har­vested, " Bates (1963) studied the impact of beaver on stream flow in Red Butte Canyon. The vegeta­tive cover was affected for approximately 91 m (298 ft) on either side of the portion of the stream in which the beaver were active, and sediment deposited behind the beaver dams in the canyon varied from 0.6 to 2,4 m (2 to 8 ft) in depth. He also noted that the small alluvial plains formed by the sediment made it apparent that during periods of high runoff, and perhaps during normal How, the dams allowed the reten­tion of quantities of suspended materials. Schef- fer (1938), in a report on beaver as upstream engineers, ascertained that two beaver dams retained 4468 m° (157,786 ft'1) of silt. It is not known whether an actual count of the number of beaver dams in Red Butte Canyon was ever made; but the environmental change effected by their ultimate displacement during the 1983 flooding of what had to have been enormous quantities oi sediment has been significant. The removal of all inactive beaver dams has inevita­bly led to the elimination of or significant reduc­tion in the density of some 55 species of typically wetland plants from once marshy areas within Red Butte Canyon. For example, in 1990 it was noted that in an area which once supported a nearly pure stand of closely spaced cattails (Typha latifolia) covering approximately 0.25 hectare (0.62 acre), only a few scattered clumps remained. According to Forest Sendee person­nel, these losses would not have been as severe had the beaver dams been active during flood­ing. Species in the following genera are among those undoubtedly affected: Eleochmis, Scir- pusyjuncus, Agrostis, Catahrosa, Desckampsia, Glyceria, Poa, Polypogon, Eqimetum, Angelica, Eetxda, Cimta, Heradeurn, Rudbeckia, Soli­dago% Barb area, Cardaniine, Nasturtium,. Rorippa, Lonicera, Cornus, Trifolnim, Mentha, Nepetaf Lenina, Epilobmm, Habenaria, Pole- nionmm, Polygonum, Rumex, AconUum, Ranunculus, Geum, Ribes, Salix, Mirmdus, Veronica, and Urtica. The U.S. Forest Service, Salt Lake Ranger District, requested the Utah Division of Wild­life Resources to reintroduce the beaver during the summer of 1991. At the time of this publi­cation, beaver had not yet been reintroduced, It is hoped that with time the plant diversity1 typi­cally associated with beaver dams will be rees­tablished. GrasS-fqrr COMMUNITY-According to Stoddart (194.1), the grasslands of northern Utah form the southernmost extension of the Palouse prairie. Of the two communities into which the Palouse prairie is divided, only that dominated by biuebuneh wheatgrass (Elymus spicaius, originally known as Agroptjron ■S'picatum) occurs in Red Butte Canyon. Rela­tively large open areas inhabited by grasses and forbs, with an occasional big sagebrush {Artemi­sia tridentata), squawbush (Rhus trilobata}, and bitterbrush {Purshia tridentata), are found chiefly below the 1829 m (6000 ft) contour (Kleiner and Harper 1966), although smaller grass-forb associations also occur in forest clear­ings at higher elevations. Some of the more commonly occurring species within the grass- forb community at lower elevations are; Achillea miUifolium Allium acuminatum Ami>msia psilostachya Arnbis holboeUii Ai'istida purjmrea (A. iongiseta) Artemisia ludi)-oiciaiw Astragalus utahensis Aster adsceridens Bakamorhiza nwtrophylla Balsamorhiza sagittata Bromus tectorum. Cirsium uncbdatum Collomia linearis Comandra umbellata- milfcil yarrow tapertip onion western ragweed Holboeii rockcress purple tlireeawn Louisiana wormwood U tah imlkvetch everywhere aster cutleaf balsaniroot arrowleaf balsamroot cbeatgrass gray thistle narrowLeat collomia bastard toadflax1992] Re d B u t t e C anyon R e sea r ch N atural a r e a 109 Crepis acuminata Cyvwpterus hngip&s $lymus trachjcmlus (Agropyron canimtm) Epdobium bmdiycarfmm (E. ptmculatum) Erigeron divergem Gatierrezia barothtai Hedysamm boreal? Heliomeris muUiflura (Viguiem multi-flora) Lovuitium f ritermtum Lufnnus (ifgenteus Microstetis gracilti Phacelia linearis Phlox longijpltd Poasecunda fP sandbergti) Stipa CAimnta Wyethia anqtlexieauUs mountain hawks beard long-stalk spfmg-parsley s leader wheatgrass autumn willowherb spreading daisy broom snakeweed northern sweetvtjtch showy goldeneye tern ate lomatium silvery lupine little polecat threadleai sco rpionweed longleaf phlox Sandberg bfuegrass net1 die-and- th read mulesears OAK-MAPLE COMMUNITY.-Cainbel oak ( Quercus gambdii) is the dominant type of veg­etation throughout the altitudinal range of the canyon. It forms what appear to he randomly spaced clones throughout much of the area. In accordance with the moisture regimen, the clones may range from thickets 0.3 in (1 ft) or less in height in dry upland sites to stands of stately, well-spaced trees in lowland areas. Both walls of the canyon support often nearly impenetrable oak in association with bigtoodi maple (Acer grandidentatum), die latter grow­ing chiefly in drain age way s. Few species thrive as understory with dense oak cover. The most common are Galium aparine (catchweed bed- straw) and Mahonia repens (Oregon grape). Others appearing seasonally under oak are Erythronium grandiflorum (dogtooth violet), Clatjtonia hmceolata (lanceleaf spring beauty), HydrophyUtim capitatum (ballhead water leaf), and H. occidentals (western waterleaf), Among plants commonly fringing oak clones are: Agoseris plmtca Apoctjnwn mtdmsawwfolium Arahis glabra Brvmus carmattis Com&ndra umhellata Delphinium nvttaUmnum D&tcurainia pinnatu Eriogonum henideoides. £, racemosum Ger/mium viseoMssititum Helumthella uniflora ffefcwnms nrnttiflora (Viguiem mukifbra) Hydrophylkim spp, Koeleria macrantha (fi crUtata) Lewopoa kUigii (Hespervchloa kingii) Lomatium dhsectum Machaernnfitera canescem mountain dandelion spreading dogbane tower mustard mountain hrotne bastard toadflax Nelson larkspur bine tansy mustard whorled buckwheat redroot buckwheat sticky geranium one-headed sunflower hairy goldeneye waterleaf Jmiegrass spike fescue giant lomatium hoary aster Merterisia brvoistyla Microseris nu tan s Phacelia heterophuJUi Poafendleriam P. praten#is Senecio i*tfegerrimus VV^atch bluebell nodding seorzonellu varilea) seorpionweed rtiutbongrass Kentucky bluegrass Columbia groundsel Mountain mahogany (Cercocarpus ledifo- Ims) occurs as individual and as scattered, mostly small populations, often in association with oak, sagebrush, or other mountain shrubs, generally on northwest-facing, sparsely vege­tated slopes. It can be seen from the main road through the canyon as small trees against the sky along the exposed, rocky, south rim of die canyon, especially toward its western end As low shrubs it occurs sporadically, chiefly on exposed dry sites above 1980 in (5500 ft). Big sagebrush {Artemisia tridentata) occurs sporadically in drier sites throughout the canyons altitudinal range. Low sagebrush (Artemisia arbuscula) occurs as relatively pure stands at about 2133 m (7000 ft) along the southeast rim o( the canyon. Con lf er o u s com m u n nr.-Do ugl as-fir (Pseudotsuga menziesii), white fir (Abies con- color), and aspen (Populas tremuioid-es) domi­nate this community, either in pure or in mixed stands, growing chiefly on north- to northeast- and northwest-facing slopes; the aspen reach as low as 1706 m (5600 ft) and the firs occur mostly above 182S m (6000 ft), Achlorophyllous Corallorhiza spp. (coralroot orchid) arc among the few plants able to flourish in the shade of dense stands of mixed conifers. Many small trees, shrubs, forbs, and grasses thrive in less dense stands or in openings between stands of trees in this community. Among them are: Acer glahrurn Amclanchier alnifom Aqutlegia coemlea Arnica spp. CastilMa spp. Ceanothus velutinus Ehjmus glaucus Erigenm spedqsus Galium spp. Hord&um brachyantiwrum Lathyrus pmicifloms Phtisacarjnis malvacetis Poa nervosa Pmrrns virginmna Ribcs uiscanssimum Rubus parviflora Sambucus spp Sorhm scopidina Sijmphoncarpus i*reopkilu$ ThahctTum fendleti Rocky Mountain maple Saskatoon servidebefry Colorado columbine arnica Indian paint brush mountain lilac blue wild rye showy fleabane bedstraw meadow barley Utah sweetpea mallow ninebark Wheeler bluegrass chokecherry sticky currant thimbleberry elderbern/ American mountain ash mountain snowherry Fendler nieadowrue110 G reat Basin N aturalist [Volume 52 Plants endemic to Utah.-Only two spe­cies occurring in Red Butte Canyon are said to be endemic to Utah: Angelica wheeleri Wats. (Mathias and Constance 1944^45! (Wheeler angelica) and Erigevon arenatioides (D. C. Eat.) Cray (rock fleabane). Angelica wheehn lias, however, been collected close to both the Idaho and the Nevada boundaries with Utah (Albee et al, 1988). Erigeron arenarioides is known from Salt Lake. Utah. Tooele* Weber, and Box Elder counties (Albee et at. 1968, Cronquist 1947). Plants introduced to Utah.-In Bed Butte Canyon, plants introduced to Utah, either from other portions of the United States or from another country, are largely restricted to road­side and trailside sites and to open grassy or rocky slopes below ,1829 m (6000 ft). Some of the more commonly occurring plants in this category are: Alysswn alyssoides Arabidfjpsis thali&na Bromus Iniziformis (B btizaefonms) B. japonicu* B. tectomm Capselfo bu i~sii pcLstoris Cyiwglofrswn officinale DactyUs glomerate Dr aba vema Erodium ciaitarmm Grindeha squarrosa Holvsteiim. miihellntom Isatis tinctoria Lactucci seniola Lep idtti 7?? perfoliattim Linaria dalmatica Uthospermun aroense Malva neglecta Melilotus alba M. officinalis Poa bulbosa Ranunculus testfcufatus Sisymbrium altissimum Taivxactim officinale Thlaspi arvense Tragoppgon duhius Veronica anci-gallis- aquaticc alyssum rnouse-ear cress rattlesnake chess Japanese or meadow chess cheatgrass shepherd's purse hounds tongue orchard grass spring draba stoi'ksbill or alfileria curlycup gumueed jagged chicfcweed dyer's woad prickly lettuce peppergrass Dalmation toadflax com grornwell cheeses white sweetclover yellow sweetelover bulbous blvegrass bur buttercup Jim Hill mustard common dandelion pennycress goats beard water speedwell The incidence of I sat is tinctoria and Linaria dahnatica increased greatly between 1970 and 1990. FtORISTIC DIVERSITY.-The following spe­cies were reported from Red Butte Canyon by Cottam and Evans (1945) and by Bates (1963). Not only is the presence of these plants unveri­fied by herbarium specimens (see Albee et al. 1988, which is based on specimens in the herba­ria of Brigham Young University, Utah State University, and the University of Utah), but at least six of them would not ordinarily occur Within the elevagonal limits of the canyon: Agmsii? semwerticilhta Arasmckw t^ssellata Angelico pinrmta *Biickdlia grandiflora Castilleja angusUfolw Cirsium floatimnH Cn/ptanifia flavocvlata Deachantjma mespitom *Erigeron ghhellus *Eriogonum ovaltfoUum G<tyopfajtum ramos Lssimu m Ger anium bicknellii Ghjcerw grandis JUncus tnertensianus * Lathy rus brachycalyx Mentzelia ajbiamlis Srirpus maritimu# *Stelforia lo^ipes Vaieruma edulti water poJypogon rough fiddleneek small-leaved angelica tasselftovwr Indian paintbrush Fiodmaja thistle yellow-eye cryplanth tufted hair grass smooth fleabane cushion buckwheat branchy ^rounckmokt? ■r Sfal? Bickoell cranesbill American mannagrass Merten's rush Rydberg sweetpea whitesteni blaming star alkali bulrush long-stalked starwort edible valerian The following species were reported by Amow (1971), but, for the reasons stated below, can no longer be considered part of the flora of the canyon: Arabis puheruta N utt. (puberuient mckcress) Calypso hulbosa (L,) Oakes (fatty sapper orchid) Carex muricaia L. (as C, angiistiar Mack) Collection identified by R. C. Rollins as an anom­alous A lemmonii Wats., the correction too late for the L971 publication, 1971 report based on a basal lea:^ no subsequent evidence of its presence available* A TntsideniificatioB. Species names now submerged with those ol other species present in the canyon (also included in section on nomenclatural changes): Arnbis divaruxnpa A. Nels = A, holboelui Homem. Bromtis oatnmutatus Schrad. - B. japoniais Thunb. Glyceria elata (Nash) M, E. Jones - G. striata (Lam.) Hitehe. Juruxis tracyi Rydb. = j. ensifolius Wikst. Taraxacum, laevigatvm (Wild.) DC. - T. officinale Wiggers Thus, the 511 species representing 73 fami­lies reported from Red Butte Canyon by Arnow (1971) can now be placed at 484 species (390 indigenous and 94 introduced) known to have Holboell rockcress i apauese or meadow chess fowl nianoaa.gr a£s swordleaf rush common dandelion *Wr!h ihe assist urictrof rbme and Leita Shts^ curator? of the ieH>aric at Brigham Young and Utah State universities, respectively, a herbarium check was nrtiide to be tsrtmn that no Butt*? Caryfm spedinsns cxi^t for those sivdes mvkd with ao astensVthm, iKtxirdiivg to Albee ei (195SI are apt in Butte Ctnyori or its v:c;ntt^r.1992] R ed B u t t e C anyon R e sea r ch N atural Area i l l 2200 c o CC $ CD 2000 1800 1600 Fig. 10 Distribution, by elevation, of tlie major plant communities in Red Butte Canyon. been present in the canyon at one time or another. Only two populations present in 1971 are definitely known to have been eliminated: Lactuca biennis (biennial wild lettuce), which was introduced into Utah from the north about 1967 but did not survive; and Solidago occidentalis (western golden rod), a single st re am side population at the mouth of the canyon taken out by the 1983-84 flooding. According to Albee et al. (1988), the 390 indigenous species reported from Red Butte Canyon (Amow 1971) also occur in at least one other canyon to the south. A mow et al. (1980) and Albee et al. (1988) i ndicate that roughly 130 native plants not found in Red Butte Canyon have been collected between an elevation of 1826 and 2438 m (6000 and SG00 ft) in canyons having a greater altitudinal range in southern Salt Lake County. This figure indicates that the floristic diversity in Red Butte Canyon, while greater than that in heavily disturbed Emigra­tion Canyon (Cottam and Evans 1945), is less than that in canyons farther south. Nomenclatural changes since Amow (1971) are listed in the Appendix, Plant Ecology Vegetation distribution.-A number of studies have focused on describing the vegeta^ tion distribution within Red Butte Canyon (Kleiner and Harper 1966, Swanson, Kleiner, and Harper 1966. Kleiner 1967). There is a strong xeric to mesic elevation gradient, with lower portions of the canyon dominated by a spring-active grassland community and the upper port ions of the canyon typically consisting of umrner-active scrub oak, aspen, and conifer­ous forest communities (Fig. 10), Composition within each of these communities is not con­stant, but instead species vary in their impor­tance within a community type as orientation and elevation change. These elevation gradients represent a continuum of moisture availability, with high temperatures and low precipitation amounts at lower elevations making conditions more xeric, while slope orientations less south­erly in exposure become progressively more mesic within an elevation band. Soil type (Fig. 5) and depth also play a major role in affecting plant distribution by providing variation in the water-holding capacity oi the substrate. The dis­tribution of the scrub-oak community to the highest elevations within the canyon is most likely related to soil conditions, since at high elevations scrub oak persists on south-, east-, and west-facing slopes that would normally be expected to be do m inated by aspen if i t were not for the very shallow, rocky soils that typify these elevations within Red Butte Canyon. Red Butte Canyon has been largely pro­tected from grazing since its acquisition by the U.S. Army almost a century ago, The conse­quence of this lack of grazing pressure at low'er elevations is a recovery to near pristine levels, and this is clearly reflected in the early commu­nity analyses of Evans (1936) and Cottam and Evans (1945). Within the scrub oak and grass­land communities of Red Butte Canyon and adjacent Emigration Canyon, a canyon annually exposed to sheep grazing, there are large differ­ences in plant density (Fig, 1L). Emigration Canyon was originally described by early pio­neers as having a dense vegetation at lower elevations. However, grazing not only reduced that cover but also increased the fraction of the plant cover occupied by ruderal, weedy species (Cottam and Evans 1945). While, plant density in Red Butte Canyon may be greater and weedy species composition lower as a result of reduced disturbance and grazing, the canyon is not free of these weedy components and historical effects (as noted in early sections). Dam con­struction during the 1920s and other U.S. Army activities within the lower portions of Red Butte Canyon have resulted in sufficient disturbance that many ruderal weedy species, such as Grindelia squarrosa (curly gum weed). Lactuca serriola (prickly lettuce), and Polygonum acd- culare (knotweed), are now common.112 Great Basin Naturalist [Volume 52 Sainuelson (1950) conducted an analysis # similar to that ol'Cottam and Evans (1945) on the algal components of the streams in Red Butte and Emigration canyons. He observed that as a result of livestock grazing and human settlement, sediment load and turbidity were much greater in Emigration than in Red Butte Creek. The consequence of this stream-quality difference was the dominance by algal genera in Emigration Creek that are turbidity tolerant, such as OsCillatoria and Phormidium. Con­versely, in the clear waters of Red Butte Creek filamentous algae, primarily No.stoc. were most common. Overall algal densities were three times greater in Red Butte Creek, owing to the greater light penetration into that stream. At the same time, Whitney (1951) compared the dis­tributions of aquatic insects in the two streams. He found that densities of aquatic insects were greater in Red Butte Creek. Of those insects persisting in Emigration Creek, there was a preponderance of species characterized by gills protected from silt, which would better allow them to tolerate the more turbid conditions in Emigration Creek, PHENOLOGY.-Plant activity is governed by two parameters; temperature and soil moisture availability. Cold winter temperatures limit growth activity between November and March (Caldwell 1985, Comstock and Ehleringer 1992). While a limited number of species, such as the early spring ephemeral Ratwnctdus tes- ticidatus (bur buttercup), may begin activity during warm periods in February; most annuals do not begin growth until the warm periods between snowstorms in early March. At lower ■r elevations, a number of herbaceous perennials such as Balsamorhiza macrophtjUa (cutleaf balsamroot) may begin to leaf out during March, but most woody perennials do not leaf out until mid- to late April. The annuals and most herba­ceous species at lower elevations have com­pleted growth and reproduction by mid-June and then remain dormant until the following autumn or spring (Smedley et al. 1991). In con­trast, woody species at lowfer elevations remain active from April through October, although the vast majority of the growth will occur during the spring (Donovan and Ehleringer 1991). At higher elevations, vegetative and reproductive growth are delayed until late May or June by cold temperatures. Plants at the higher eleva­tions will remain active throughout the summer, 30 20 ? o o 10 B Red Bjtte □ Emigration 1515 ‘625 1700 2060 Transect elevation, m Fig. 11. A nomparison ot the plant cover ill open grass­land communities of different elevations in Red Butte and Emigration canyons. Adapted from Cottam and Evans (1945). even though there may be little summer precip­itation (Dina 1970, Dina and Klikoff 1973). Adaptation.-In the nonforested portions of the Intermountain West, plant growth is largely restricted to spring and early summer periods by cold temperatu res du ri ng winter and imited water availability during the summer (Caldwell 1985, Dobrowolski, Caldwell, and Richards 1990. Comstock and Ehleringer 1992). A number of recent reviews have addressed adaptation characteristics of plants growing in these emironments (Caldwell 19S5, DeLucia and Schlesinger 1990. Smith and Knapp 1990. Smith and Nowak 1990). For the most part, plants within Red Butte Canyon are exposed to a hot, dry environment, with little relief from developing water stress during the summer months. The only clear exception to this pattern is the series of plants within the riparian com­munities along the canyon bottom. To gain a better understanding of this occurrence, many of the recent ecological researchers within the Red Butte Canyon RNA have focused on mech­anisms by wllich plant species have adapted to limited water availability. Among the first ecophvsiological studies was that by Dina (1970). who examined water stress levels of the dominant tree species in the lower portions ol the canyon: Acer grandidentatum (bigtooth maple), Acer negtmdo (boxelder), Artemisia tridentata (big sagebrush), Purshia tridentata (bitterbrush), and Quercus gambelii (Gambel oak). Dina (1970) observed that1992] Bed Butte Canyon Research Natural Area 113 6 o E o E E > o c Q> 0 ■ mmm 4- 0 0) co D 1 CD 2 forbs 1 0 April May June Fie 12. The mean water-use efficiency values for grasses and forbs within the grassland community of Red 'Utte Canyon during main period of tlie growing season. Water-use efficiencies were calculated from carbon isotope discrimination values from Smedley et aJ. (1991) and the vapor pressure data in Figure S. midday leaf water potentials of - 30 to - 65 bars develop in perennials occupying slope sites during late summer, whereas water potentials of adjacent riparian tree species are maintained between -20 and -30 bars during the same periods. Water potentials in the range of -10 to -15 bars cause many crop species to wilt and close their stomata, reducing transpirational water loss. Tolerance of water stress levels as low as -40 to -60 bars is thought to occur in only the mosl drought-adapted aridland species. These late-summer water potential values on slope species are sufficiently low to close sto­mata and reduce photosynthesis to near zero values. In Dina's (1970) study photosynthetic rates of riparian species decreased by 50-80% from nonstress values, but riparian trees were able to maintain positive net photosynthetic rates throughout the summer. More recently, Dawson and Ehleringer (1992) and Donovan and Ehleringer (1991) conducted related stud­ies and again observed that photosynthetic carbon gain of slope species is largely limited to spring and earl}' summer, whereas riparian spe­cies are able to maintain photosynthetic rates throughout the year, albeit that photosvnthetic rates are lower in summer than in spring. Two common responses to limited water availability are avoidance and tolerance. Avoid­ance of water stress is accomplished by comple­tion of growth and reproductive activities before the onset of the summer dr ought, whereas toler­ance is associated with the evolution of features that allow plants to persist through die drought period. Several interesting studies have been con­ducted in Red Butte Canyon that shed light onto the nature of a plait's ability to tolerate water stress and persist through time. Treshow and Harper (1974) examined longevity of herba­ceous perennials in grass, mountain brush, aspen, and conifer communities throughout the canyon. They obseived that life expectancies of dominant herbaceous perennial species, such as Astragalus utahensis (Utah n11!kvetch), Bcdsa- mofhiza inacropktflla (cutlcaf balsamroot), Hedy santmbo reale (northern sweetvetch), and Wyethw amplexicattlis (mulesears), are rela­tively short (3-20 years) when compared to the longer-lived (>65 years) grass species, such as Agropyron spicatwn (bluebunch wheat grass) and .Stipa eomata (needle-and-thread'. The inability to persist through successive drought years may be one of the reasons that dicotyle­donous species have shorter life expectancies than monocot) !edonous species. Related to this, Smedley et al (1991) examined the water-use efficiency of these and other herbaceous grass­land species. Water-use efficiency, the ratio of photosynthesis to transpiration, serves as a mea­sure of how much photosynthetic carbon gain occurs per unit water loss from tlie leaf. Dicot herbaceous perennials had consistently lower water-use efficiencies than their monocot coun­terparts (Fig. 12). The differences in intrinsic water-use efficiencv withm this life form mav be a major contributing factor to the shorter life expectancy in dicot herbaceous species. Consis­tent with this pattern, Smedley et al. (1991) observed that water-use efficiencv of annual species is significantly lower than that of peren­nial species in grasslands along the lower por­tions of the canyon. They also observed that m _ # perennials which persist longer into the summer drought period have higher water-use efficien­cies than those species that became dormant in late spring. During 1988-90. precipitation was unusually low. The effects of the three-year drought are now seen in Gambet oak and bigtooth maple at their lower distribution limits, especially on shallow soils, where stem dieback has become prev alent.114 Cheat Basin Naturaijst [Voluing 52 10 cm March April May Fi^. 13. Height of ( i/i•'(< >',t!rnt Ion"i{i<iihovv tlte ground surface itt difTuwBt months during the spring growing season, After Werktttaf. (1986). ' ‘ .... Ehleringer (198S) examined leaf-level adaptations ol plants along the entire elevational transect within Red Butte Canyon. This study focused on determining patterns of leaf angle and leaf absorptance variation among species within communities exposed to different degrees of drought stress. Increased leaf angle and decreased leaf absorptance reduce the solar energy incident on leaves and are viewed as ev mechanisms tor both reducing leal energy loads (reducing leaf temperature) and increasing water-use efiiciencv. Along a transect from grassland tlirough coniferous forest. \'oiy few plant species exhibit: any significant changes in leaf absorptance, However, leaf angles among species become progressively steeper in drier habitats. Phis pattern is consistent with the notion that as plants are exposed to progres­sively drier environments, the general adaptive response of species within the community' is to increase leaf angle, thereby reducing incident solar radiation levels. In the grasslands on the lower portions of o r Red Butte Canyon is a most unusual plant sjk1- cies, Ciftnoptenis longipes (long'stalk spring- parsley). Sometimes known as the "elevator plant," C. longipes is a prostrate herbaceous perennial with an elongating pseudoscape (a scape is a leafless flowering stalk arising from ground level; the pseudoscape is an elongation of the leaf-hearing stem in the region between the roots and existing leaves). Other CyrrkYpterus species also have a pseudoscape, but in none of the other species is it as well developed as in C. lorigipes. In spring, solar heating of the ground surface increases soil and !eai temperatures and can result in moderately warm leaf temperatures (30-35 C). These tem­peratures are substantially higher than the opti­mum photosynthetic temperature for the eleva­tor plant and result in both a decreased photosynthetic rate and a decreased water-use efficiency (Werk et al. 1986'. To increase both af the rate of photosynthetic carbon gain and water-use efficiency, the pseudoscape elongates as spring temperatures progressively increase {Fig. I 3). The result is that what was once a prostrate canopy is elevated above the warm soil surface and now exposed to cooler air tempera­tures abovC the ground surface. Werk et a!. (1986) showed that the rate at which the psuedoscape elongates is dependent on die rate of soi 1-surface heating. Plants from protected or north-facing sites elongate less than those from exposed, southerly .sites. Donovan and Ehleringer (1991) examined relationships between water use and the likeli­hood of establishment bv common shrub and J tree species in the lower portions of Red Butte Canyon. They observed that photosynthesis is greater in seedlings than in adults throughout most of the growing season, but that water stress and water-use efficiency are lower in seedlings. Seedling mortality in several of the species is associated with higher water-use efficiencies, suggesting that mortality selection occurs With greater frequency in seedlings that are conser­vative in their water use before they have estab­lished sufficiently deep roots to survive the long summer drought periods Few studies have addressed ecophysiologi­cal aspects oi riparian ecosystems in the Inter­mountain West. This is somewhat surprising since riparian ecosystems are most often among the first to be damaged by human-related aetiv- *5 J ities. from outdoor recreation to waterDBH of main tree trunk, cm Fig, 14, Hydrogen Isotope ratio of stem water: of tliree common streamside ant! itdiacenr nonst reattisdt trve species in PaHeys For); of Bed Bint'.- Canyon as u function ol the- diameter at breast height of die main trunk, Plotted as gray Kirs liiv also the hyilrogcn isotope? ratios of the three possible water sources Tor these plants: loeal precipitation, stream water, and srm.mdwater. ©pen symbols represent streamside plants and closed symbols represent nonstreamside plants, Adapted from Dawson anti ifhJennEer (ISUi). impoundment to grazing. Pied Butte Canyon, as one if the few remaining riparian systems in the Intermonntain West not severely impacted by human activities, is ideal for studies of the adap­tations of riparian plants and for comparative studies of species sensitivities to human-related activities. In a recent studv Dawson and Ehleringer (1992) examined water sources used by riparian plants species. In I Iteir study, plants were segre­gated according to niicrohabitat and size: stream side versus nonstreamside and juvenile versus adult (based on diameter at breast height). Their results were rather startling and suggest that a new perspective is necessary' when evaluating riparian communities, their establishment potentials, and their sensitivity to disturbance. Dawson and Ehleringer (1991) used hydrogen isotope analyses of stem waters to determine the extent to Which different cat­egories of riparian trees utilize stream water, recent precipitation, or groundwater. Hydrogen isotopes are not fractionated by roots during water uptake; therefore, the hydrogen isotope ratios of stem water will reflect the water sources currently used by that plant. Rain, groundwaters, and stream waters differ in their hydrogen isolope ratios, providing a signal dif­ference that could he detected by stem-water analyses. Dawson and Ehleringer (1991) observed that among mature tree species none were directly using stream water (Fig. 14). All were using waters from a much greater depth, which had a hydrogen isotope ratio more nega­tive than either stream water or precipitation. Young streamside trees utilized stream water, O ...... , but only when small. Young trees at nonstream­side locations utilized precipitation, having access to neither stream water nor deeper groundwater. One possible reason that stream- side trees mav not depend on stream water is that this surface water source may occasionally dry up during extreme drought years and become unavailable to these trees; another is that stream channels occasionally change their course, and dependence on .surface moisture would then result in increased drought stress and likely increased mortality rates. The long­term stream discharge rates suggest that stream116 G re at Basin Naturalist [ Volume 52 water may he less dependable than deeper groundwater sources (Fig. 6). Many plants do not contain both male and female reproductive structures in their [lowers, but are present as either male or female plants (dioecy). Freeman et al. (1976, 1980) noted that dioeey is a common feature of plants in the Intermountain West. Furthermore, they observed that the two sexes are usually not ran­domly distributed across the landscape. Rather there is a spatial segregation of tlie two sexes such that iemales tend to predominate in less stressful microsites (wetter, shadier, etc,), whereas males occur with greater frequencies on more stressful sites (drier, sunnier, saltier, etc.). In Red Butte Canyon, Freeman et al. * (1976) investigated spatial distributions of Acer negundo (boxelder, a riparian tree) and Thalia- trumjendleri (Fendler meadowme, a perennial herb). In both species, there was a strong spatial segregation of the two sexes. Dawson mid Ehleringer (1992) have fol­lowed up on the initial observations of spatial segregation iwAcernegwidv (boxelder), seeking to determine whether intrinsic physiological differences among the sexes may contribute to plant mortality in different microsites. They observed that female trees have significantly lower water-use eJficiencies than male irees on both stream side (where female predominate) and nonstream side locations (where males pre­dominate}. Male trees exhibit a higher water- use efficiency in dry sites than in streamside locations, but female trees exhibit no such response across microhabitats. The lack of a change in water-use efficiency by female trees on dry, nonstreamside locations may contribute to an increased mortality rate, which then ultimately results in a male-biased sex ratio at these sites. The mammalian fauna of Red Butte Canyon is remarkably diverse, due in part to the altitu- dinal gradient and numerous small patches of various plant communities indigenous io the area. A particularly rich small mammal fauna is associated with the patches of riparian habitat along Ked Butte Creek and its tributaries. Prior to die run-off of 1983., riparian habitats were much more extensively developed than at pres­ent. Numerous marshy meadows existed in association with large, active beaver dams prior to 19S2. The loss of active beaver dams in the early 1980s has doubtless greatly reduced the populations of small mammals that are restricted to die mesic-marshy habitats of the canyon, Nonetheless, based on the altitudinal gradi­ent and vegetational diversity of Red Butte Canyon, a total of 51 species of mammals should hypothetically occur there. Below is a list of the 39 species of mammals known to occur in Ked Butte Canyon. j KsECTJVOjS A-SniUCIDAK Sorex ptfkislfis water shrew Sorex Vflgmm wandering shrew Sorex cineiws masked shrew Cm kopteha-Vest Ercrn jonadar Eptesicus fuscus big brown hat LaCOMOIU'Ha-LEFOitlDAtf Lepm towmendi Sijlvilagus nuttallii while-tailed jackrabbit Nuttall cottontail Rode ntia--Sc i u R \ dal; TaflliaschtTlis hiuhonicys red squirrel Marnwtajlavivfmter yellpwdbellied marmot Spertnophih^ urrmtius Uinta ground squirrel Spermophilus van( ^!tu^ rock squirrel Eutamias mittimus 1 east chipmunk Glaucomas salninix& northern %ins; squirrel Rodent? a-Get \um>AE Thomormjs talpoides northern pocket gopher Thonumim hotiae botta pocket gopher Rod k ntj a-Gasi t > tuDaf Castor canadensis beaver RODEVTiA-MUKIDAE Reithrodontoimfi nicgdotti western harvest mouse Peromy$fiu$ nwnicidutiis deer mouse Fenytmjscus hoylii brush ftiouse Clethrioni'>mtjS gapperi red-backed vole Ondatra zibethicu# muskrat Pkenai'omtjs tattirrnedittf heather V&le Microtus numUmm montane vole Microtun fon0ciiudti$ Ibng-t.ailed vole Aroimla risJiardsoni water vote Rudentia-Zafodibae ZGpus princeps western jumping mouse R C)D E NT 1A-E UETH1ZO NTT DAE EfTthizon dnrsaturrt porcupine Ca hktvo ua -Canidae Cattfa l&trans coyote Ca w Nm j \ ia-P ftOCTON r dae Ba&sariscm tistutus ring-tailed eat Pwcyon htoi racoon CaKMEUOKA - M USTtti i UA El Musteki freruita long-tailed weasel Musteld ertninca ermine Mnstel# vis cm miuk Taxkha taxus Badge* Mephitis mephitis stuped skunk Carnivoiu-Frlidae Lynx m/us bobcat Fells concolor mountain lion A htjoda< rmA-Cervidae Cerwtf cantubtnsis elk Otbcuiletis h&mionus mule deer Akes fimericanits rrsoo.se Mammalian Fauna1992] Red Butte Canyon Research Natural Area 117 Some of the larger species have been observed only occasionally, such as die bobcat, mountain lion, and moose. But others such as the mule deer, elk, and coyote are observed widi high frequency at some seasons. A rather rich rodent fauna inhabits the canyon, with many of the species preferentially occupying the moist riparian communities of grasses, forbs, and shrubs. Thus, the red-backed vole, heather vole, montane vole, long-tailed vole, water vole, and jumping mouse are virtually restricted to the small mesic meadows along Red Butte Creek and its tributaries. Similarly, the three species of shrews in die canyon are distributed almost exclusively in the riparian habitats. In some larger meadows, such as along Par­leys Fork and at Porcupine Gulch, the microtine rodents are distributed in a strongly zonal pat­tern. Long-tailed voles are found in the driest parts of the meadows, montane voles in the more mesic areas where grasses, sedges, and forbs comprise a diverse community, and water voles in the immediate stream Side area, their burrows often entering the bank at the water's edge. Red-backed voles and heather voles are typically found around the bases of willows in the meadows, as well as around the edges of conifers at higher elevations. A few species are found only at higher eleva­tions in association with Pseudotsuga menziesii (Douglas-fir) and Populm tremuloides (aspen). These include the red squirrel, Uinta ground squirrel, yellow-bellied marmot, and least chip­munk. The oak-mountain mahogany zone seems to be die preferred habitat of the rock squirrel and perhaps the ring-tailed cat as well. Several dissertations dealing with the ec. ology and physiological adaptations of shrews, microtine rodents, and jumping mice have utilized study sites in Red Butte Canyon (Forslund 1972. Cranford 1977), Avian Fauna In his study of the birds of Red Butte Canyon, Periy (1973) found that 106 species occurred in die area during his study. Of these, 32 species are permanent residents and 44 are summer residents. The remainder (30) are migrants or winter residents. The permanent resident birds include: FaLCONIFOHMES-ACCIPITRtDAE Accipiier gent Uis Goshawk AccipUer stiiatus Sharp siiinucd Hawk Accipiter cooperi Cooper's Hawk G ALLircmM ES-TETKaONIDaE Dendraeapus obscitrus Bonasa umbeUus Gallifohmes-Ph a sia nidae Lophortyx calif amicus Phasiantts colckUtis Alectaris graeca STiUGtFOHMES-STMOIDAE Oto flammeokii Bubo virgtTuanus Asio Qtus CORACIIFORMES-Al/CEDINIDAK Megoceryle alcyon FICIFOHM ES-PlClDAE Calaptes cafer Sphyrapicus varias Dendrocopus inUosus Dendrocopus pubescens PaSSEMFOkM ES--CO BV1 DAE Cyanocitta stdlen Aphektcoma coarulesc-ens Pica pica pASSEFUPORMES-PAJUDAE Pams atricapHlw Pams £titnbt;h Psaltiiparus minimus PassErifohmes-SirrtDAE Sitta canadensis PASbEKlFOli MES-CERTHJJDAF Ceithiajamdiaris Passerifohmes-ClNCUDAE Cinciw itoexicanus Pass erifor mes-Tt jrdidae Myadeste$ tmvnsendi Passebifoames-Sylvudae Regulus satropa Passerifor S1ES-Stukntdae Stumus vulgaris Passeki formes-Ictebidae Stumpila neglect a Passehifohwes-Fringiludae Carpodacus mexicanus Spimts pirn is Junco oreganos Blue Crouse Ruffed Grouse Ca] ifornia Quail Ring-necked Pheasant Chukar Flammukted. Owl Great Homed Owl Long-eared Owl Belted Kingfisher Red-shafter Flicker Yellow-bellied Sapsucker Haii)' Woodpecker Downy Woodpecker Stellers Jay Scrub Jay Magpie Black-capped Chickadee Mountain Chickadee Common Bushtit Red-breasted Nuthatch Brown Creeper Dipper Townsend's Solitaire Golden-crowned Kinglet Stalling Western Meadowlark Hou Finch Pme Siskin Oregon [unco In addition to the species that are permanent residents in Red Butte Canyon, the following list of summer residents represents species that probably also nest in the canyon: AN5ER [FORM ES-ANaTIDaE Anus platyrlupu.kos Falcon ufohmes--Aocipit w dae Buteo farnaicensis Aquila chrysmtoS F ALCOMI TOR M £5-FALCOtf IDAE Falco sporverius Sparrow Hawk C HA RADKIIFO HM ES- SOQLOrACUDAE Mallard Duck Red-tailed Hawk Golden Eagle Acffifs mactdarla COLUMBIFOHMES- COUJMBIDAE Jenmdura m/icrowa Apodjpormes-Trockilidae Archilochus alexandri Selasphorus plati/cercus P ASSEHIFOH M ES-TY HANNlDAE Empidutuix oherholseri Spotted Sandpiper Mourning Dave BJark-chiiined Hummingbird Broad-tailed Hummingbird Dusky Flycatcher118 Great Basin Naturalist [Volume 52 Evipulonfix d ifficilis Western Flycatcher Cma&tyHu sijrcJuhihis Western Wood Pee wee rjji MRS- HmUNptivi l>aE Tachijcim'Xa thuhissina Violet-green Swallow lmU>prtKTv bicvlor Tree Swallow Ripuria riparUi Bank Swidlow Std^idopta ifx ntfiatllis Rrm^h-winged Swallow Hmtntlo nislica Bain Swallow Fetrovhvlidon pyrrhonota (.'lifl Swallow Passehifokmes-T itGCf yfot)yi ida.e Tn*glodytes tnxhm House Wren Salpi nctes ubmlzhix Rock W ren -Turdhmk Tardus miffiat&rnts Robin UijlocAchla guttata 1 lermit Thrush Htfbxdchln ustulata Swainsou s Tlmisli Sialia ainiwoidex Mountain Bluebird PA^SlvKlFOHMJ'S-SVLVJIDAE Fulioptifa (oendea Bhio-gruy Cnuieafclier P ANSKRTFOH -Vt HKON IDA FI Virett gift™ Warbling Vineo 1*AA>K >HMES--PaIIUI J1MK Venniwm cduta Ortuige-crowwd Warbler Vcrutivom rrrginiae V irginias Warble* Vendroica petechia Yellow Warblt.T DtmdroU-it (mduhofti Audubon $ Warbler Qpttrorrite (ohuk i MjcGSlEivr^yV W#hler VViZscwii^ mtsilfo Wilson s Waihler P^KSEJUrtfU MKS-ICTK Kt J >A ft Icivrtis buUickii Bullocks Oriofe Molothnts ater Brown-headed Cowbt td PASSKKirOHMKS-TflRAUL'IUAE Viraniitt lud<>inciana We?''tern Tar11iger PaSKEJUFOIIMKS-FWNCILUDAE Vhcuticus mdawtmphalus Bluckheiujed Grosbeak Fdsserina mtwerta Lazuli (hinting C1 C(ir}w({tn.w$ (gissinii Cos sin's Finch SpiituS tristix American Goldfinch Chiomnt ehltmtrri Green-tailed Towliee Fip:L) litythrothubniifi LUilous-sided Tmvhee Paoeadas in'amineua Vesper Sparrow funci) ainiceps C»ray-headed Juneo SjiheUe passatfna Chipping Sparrow aiasiiim m<\',(uc 'Kttig Sparrow Role of Research Natural Areas Research Natural Areas provide several spe­cific advantages to the nations scientific qorn in unity, which are typically not otherwise available. These include potential use ot an area that has had minimal human interference and lias a reasonable assurance ol long-term exis­tence, and the potential association and interac­tion of scientists from different disciplines leading to discoveries unlikely to occur without such an association. Conducting research at common locations is key to developing these interactions. Research Natural Areas not only assist in the progress of basic science, but also provide federal and state agencies with informa­tion upon which to base management decisions. The melding of ecosystem preservation and research on basic ecological processes at Research Natural Areas provides numerous valuable options to society. The Red Butte Canyon RNA serves this purpose well. Although initially affected by human activities during the early settlement of the Salt Lake Valley, the jr -r canyon was soon set aside by the federal govern­- / ment and has now had nearly a century to recover (though the loss of beaver represents a significant impact to the ecology ol the riparian ecosystem). Other canyons in the Wasatch Range have not received equivalent protection, As we move into the twenty-first century, v ■ there will be increasing pressure to understand the dynamics of ecological systems and man s impact on ecological processes. Maintained as a protected watershed, the Red Butte Canyon RNA provides a unique opportunity for addressing these important issues to human society and to the preservation of our environ­: ■ ment. Unprotected, it is an invaluable resource lost Forever. Federal Iand-managenlent agencies have been developing a national system of Research Natural Areas since 1927. More than 400 areas have received this designation nationally. Since C? ^ inception of the RNA Program, there have been two primary purposes for Research Natural Areas: 1. to preserve a representative array of all significant natural ecosystems and their inherent processes as baseline areas; and 2. to obtain, through scientific education and v7 research, information about natural system components, inherent processes, and com­parisons with representative manipulated systems. Literature Cited An asterisk (") refers to studies conducted in Red Butte Canyon, but not specifically cited in this manuscript. Albf:k. B. J., L, M, Shultz, and S. Goodiiich. I9S\ Atlas oft he vascular plantsoi Utah. Utah Museum ol Natural History, Salt Like City. 670 pp. Anonymous, lUo-t. History oj Fort Diiiiglas. Compiled by Fori Douglas Army Engineers Office* Am now. J* A. 197], Vascular flora of Rixl Bulte Canyon, Salt Lake Count). Utah. Masters thesis. University of Utah, Salt Lake City. 383 pp. ____. 1 MS I, Foci secunda Presl. versus P. sandbar^ii Vascy fPoaeeae). Systematic Botany 6: 4.I2-42.L. ____1987. Cramineae. Pages 684-7SH in S. I „ Welsh,1992] Red Butte Canyon Research Natural Area 119 N, Ahrood* L. C Higgins, and S. Goodrich. A Utah flora. Brigham Young University Press, Provo. Utah. Arnow. L. A,, B. Albee, and A. WVckoff 1980. Flora of the central Wasatch Front, Utah. Utah Museum of Natural History. Sal* Lake Gty, 563 pp. AJUUNGTON. L. and T G, ALEXANDER- 1965. The U.S. Army overlooks Salt Lake Valley, Fort Douglas 1862^- 196-5. Utah Historical Quarterly 33: 327-350. Bates, J. W. 1963. The effects of beaver on stream flow. Job Completion Report for Federal Aid Project W-65TL Utah State Department of Fish and Game Information Bulletin 63-13. 87 pp. Billings. W D 1951. Vegetation zonation in the Great Basir: of western North America. In: Les fosses ecologiques de la regeneration de la vegetation des zones arides, International Union of Biological Sci enoes Series B ColEoqulaS: 101-122, _____* ? 990. The mountain forests of Nordi .America and their environments. Pages 47-36 in C. B* Osmond. L. F. Pitelka, and G- M. Hidy, eds., Plant biafogy of the Basin and Range. Springer Verlag, New York, Bond, 1-1. W, 1977. Nutrient dynamics of undisturbed eco­systems. Unpublished doctor al dissertation, University of Utah. Salt l^ake City. _____r. 1979. Nutrient concentration patterns in a stream draining a montane ecosystem m Utah. Ecology 60 > 1184-1196. fBu£w$TEB, W. 1951. GcJl wasps producing falls on the scrub oak Que*~Gu$ gambelii Nutt. Unpublished masters thesis* University of Utah, Salt Lake City. Caldwell, M, M. 1QS5. Cold desert. Pages 19S-212 in B. F. Chabot and IS. A. Mooney, eds.. Physiological ecology of North American plant communities. Chap man and Hall, London. COM>~roeK, J, F-, and], R. Eulkkingek, 1992. Plant adap­tation in the Great Basin and Colorado Plateau. Great Barin Naturalist. In press. Cottam W P.7 and F. Evans. 1945. A comparative study of grazed ted ungrazed canyons of the Wasatch Range* Utah. Ecology 26: 171-181. CfaMfokd, J. A. 1977. The ecology of the western jumping mouse Unpublished doctoral dissertation. University of Utah. Sa^t Like City. •CnoET. A. R.> L, Woodward, and D. A. Anderson 1943. Measurements of accelerated erosion on range-water­shed land. Journal of Forestry 41: 112-116. CRONQD15T, A, j. 1947. Revision of the North American species of Erigeron, north ol Mexico, Brittonia 6: 121 302. ^ ____. 1961. An integrated system ol classification of flow ering plants. Columbia University Press, New York. 1262 pp. Dau BEN MIRE, R. F. 1943. Vegetationa! zonation in the Rocky Mountains. Botanical Review 9: 325-393. Dawsom, T- E., and J. R. EiiLERFNGBF.. 1991. Streamside trees that do not use stream water. Nature 350: 335­337. ____. 1992. Gender-specific physiology, carbon isotope discrimination* and habitat distribution in boxelder, Acer negundtt Ecology. In press. DeLUCIA* E. H,,andw. H. Sculesingek* L990, Ecophys­iology of Great Basin and Sierra Nevada vegetation on contrasting soils. Pages 143^17SmC. B. Osmond, L. K Pitelka* and G. M. Hidy, eds,. Plant biology of the Basin and Range. Springer Verlag, New York. DtNA± S J. 1970- An evaluation of physiological response to water stress as a factor influencing the distribution of six woody species in Red Butte Canyon, Utah- Unpub­lished doctoral dissertation, University of Utuh, Salt Lake City. Djna., S. J-, and L, G, Klikoff 1973. Carbon dioxide exchange by several stream side and scrub oak commu­nity species of Red Butte Canyon, Utah. American Midland Naturalist 89: 70-80, Dobrgwolskl J. P., Ml M Callwrll. and J. M. Rich­ards. 1990* Basin hydtology and plant root systems, Pages 243-292 in C, B. Osmond* L, F. Pifelka, and G. M, Hidy, eds., Plant biology of the Basin and Range, Springer Verlag, New York. Donovan. L, A*f and J. R Ehlf^jnc;e4 1991. Econhysio- logica! differences among pre^reproductive anrf repro­ductive classes of several woody species ^ Oecologia S6: 594-597. ' EhleuiNGEH. J* R. 1983. Changes in leaf characteristics of species along elevation a! gradients in the Wasatch Front, Utah. American Journal of Botany 75: 690-689* EvAMb, F. F\. 1936 A comparative study of the vegetation of a grazed and ungrazed canyon of the Wasatch Range, Unpublished masters thesis, University of Utah, Salt Lake City. Fojislund. L. G> 1972. Endocrine adjustments in Microtm montanus populations from laboratory and natural environments. Unpublished doctoral dissertation, Tulane University, New Orleans, Louisiana. ME&MAK D, C., K« T. and W K- Ostleh 1980- Ecology of plant dioecy in the mtennountam region of western North America and California. Oecologia 44: 410-417. FKRgjMAN, D. C, L, G. KLTfcOFiv and K, T. Hamper, 1976. Differential resource utilization by the sexes of dioe­cious plants. Science 193: 597-599, Hely, A. G., R. W, MpwEft, and C, A. Harr 197], Water resources of Salt Lake County, Utah Utah Department of Natural Resources Technical Publication 3L HlBBAKD, C- G- 1980. Fort Douglas, 1862-1916. Unpub­lished doctoral dissertation, University of Utah. Salt Lake City. Houghton, J_ G. 1969, Characteristics of rainfall ir\ the Great Basin. Desert Research Institute, L-niversity of Nevada* Reno. 205 pp. "James. F. K., Jr. 1950. The ants of Red Butte Canyon. Unpublished masters thesis, University of Utah, Salt Lake City KleIneh. E, F. 1967 A study of the vegeftitiomt) communi­ties of Red Butte Canyon, Salt Lake County, Utah, Unpublished master? thesis, University of Utah, Salt Lake City. 53 pp, Klf^inek, E. F., and K* T. Hakpek, 1966. An investigation of association patterns of prevalent grassland specter in Red Butte Canyon, Salt Lake County, Utah. Utah Academy of Science. Arts* and Letters 13: 29-,36. La ffekty, K. M. 1949. A preliminary study of the spiders of Red Butte Canyon. Unpublished masters thesis, University of Utah, Salt Lake City. Ld-LLtNCEH. D. B 1985. Ferns and fern allies. Smithsonian Institution Press, Washington, D C, 389 pp, Maxell, R. E.. and R. L. Titref/t 196*0. Geologic map of Salt Lake Count); Utah Utah Geological and Mlneral- ogical Survey Reprint Series, R.S. S3. Scale 1:62,500, Mathias, M. E., and L, Constance. 194^45, Umbelliferae. North American Flora 28 B: 43-297. Negus, N. C.. P. J. Berger, and L. G. Fokslund 1977, Reproductive strateg)^ of Microtws numtanus. foumal of Mammalogy 5S: 347-^353- Petiry, M. L, 1973. Species composition and density of the120 Great Basin Naturalist [Volume 52 birch of Red Butte Canyon. Unpublished masters thesis, University of Utah, Salt Lake City. 'Peterson. B. V. 1953, Taxonomy and biology of the black flies oi Salt Lake County. Unpublished master's thesis, University of U tah, Salt Lake City. SamuELSON. J. A. 1950. A. quantitative comparison of the algal populations in two Wasatch Mountain streams. Unpublished masters thesis, University of Utah. Salt Lake City. Sckeffeji. V B. 1938. Management studies c! transplanted beaver in the Pacific Northwest. North American Wild­life Transactions 6: 320-326. Sieren, D. 1. 1981. The taxonomy of the genus Enthamiu. Rhodora S3: 557-579. Smedley. M. P., T. E. Dawson. J, P. Comstock, L, a. Donovan, D. E. Sherrill. C. S. Cook, and J. R. Ehuerincer 1991. Seasonal carbon isotnpic discrim­ination in a grassland community. Oecologia 85: 314­320. " Smith. S. D., and R. S. Nowak. 1990. Ecophysiology of plants in the intermountain lowlands. Pages 170-2* 11 ui C, B. Osmond L. F. Pitelka, and G. M. Hid)-; eds.. Plant biology of the Basin and Range, Springer Verlag, New York. Smith, W. K., and A. K. JCnapp. 1990. Ecophysiology of high elevation forests. Pages 87-142in C. B. Osmond, L, F. Pitelka. and G. M. Hidy, eds., Plant biology of the Basin and Range. Springer Verlag. New York. Stoddaht. L A. 1941. The Palouse grassland association in northern Utah. Ecology 22:158-163. Swanson, G,, E. Kleiner, and K. T Harper. 1966. A vegetational study of Red Butte Canyon, Salt Lake County, Utah, Proceedings of the Utah Academy of Science. Arts, and Letters 43: 159--160. 'Treshow, M., and K. T. Harper. 1974. Longevity of perennial forbs and grasses. Oikos 25: 93-96. Treshow, M., and D. Stewart. 1973. Ozone sensitivity of plants in natural communities. Environmental Conser­vation 5: 209--214. Tryon. R. M., and A. F. Tryon. 1982. Fems and allied plants, Springer-Verlag, New York. 857 pp. Van Horn, R., and M. D. Chittenden, J*. 1987. Map showing surlicial units and bedrock geo logy of the Fort Douglas Quadrangle and parts ol the Mountain Dell and Salt Lake City North Quadrangles, Davis, Salt Lake, and Morgan Counties, Utah, U.S. Geological Survey Miscellaneous Investigations Series, Map 1­1762. Scale 1:24,000. " "VfcXEHY. R. K., Jr 1990. Pollination experiments in the Minvulus cardkialis-M. ieuTSii complex. Great Basin Naturalist 50: 155-159. •Waser. N. M., R. K. Vickery, Jr.. and M . V. Phsce 19S2. Patterns of seed dispersai and population differentia­tion in Mimulus guttatiis. Evolution 36: 753-761. Weber. W. A. 1987. Colorado flora: western slope. Colo­rado Associated University Press, Boulder. 530 pp. Weber W. A., and R. Hartman 1979. A North American representative of a Eurasian genus. Phytologia 44:313­314. Welsh, S. L., N. D. Atwood, L. C. Higcins, and S. Goodrich. 1987. A Utah flora. Brigham Young Uni­versity Press, Provo, Utah. 894 pp. Werk, K. S.. ]. R. Ehlehincek, and P. C. Harley. 1986. Formation of false stems in Cymoptems lotigipes: an uplifting example of growth form change. Oecologia 69: 466^470. Whitney, R. R. 1951. A comparison of the aquatic inverte­brates of Red Butte and Emigration Creeks. Unpub* lished masters thesis, University of Utah, Salt Lake City. Woodward, L,, J. L, Harvey, K. M. Donaldson, J. J. Shiozaki, G. W. Letshman. and J. H. Broderick. 1974. Soil survey of Salt Lake- area, Utah. U.S. Soil Conservation Service in Cooperation with Utah Agri­cultural Experiment Station. 132 pp. Received 14 November 1991 Accepted 1 June 199'2 APPENDIX Nomenclatujral Changes in the Flora, 1971-1990 The following is a list of nomenclatural and orthographic changes made since publication of the Vascular Flora of Red Butte Canyon, Salt Lake County. Utah (Amow 1971), Family names of flowering plants are changed to accord with those used by Cronquist (.1981), All other name changes are contained in Welsh et al. (1987) unless otherwise specified. amakanthaceae Amaranthus praecizans of American authors, not L, = A blitoidcs Wats. AMARYLLIDACEAE = Lit. [ ACE A E Brodiaea douglasii Wats. = Trtteleki grandifiora Lindl. Anacardmceae Bhus radicnns L - Toxicodendron njdbergU (Small) Greene Berberudaceae Bei'betrs repens Lind). - Mahorua repens (Lindl.) G. Don Boraginaceae Cruptantha nana (Eastw.) Pays. - Crtiptantha humilia (Gray) Pays. Haekelia jessicae (McGregor) Brand - H. micmtit-ha (Eastw.) J, L, Gentry' Lapvidn echinnta Gilib. = L. squarrosa (Retz.) Dumort. (Weber 1987) Cactaceae Opuntw aurea .Baxter, misapplied to O. mctcrorhiza Engelm. Cahyophyllaceae Cerastntm vulgatum L. = C. fontanum Baumg. Stellaiia jamesiann Torr. - Pseudastellaria jameswui [Torr.} Weber & Hartman (Weber and Hartman 1979) C EL ASTR ACE AE Fachistima - Paxistima Chenofodiaceae Salspla kah L. = Salsola iberim Sennen & Pau COMPOSITAE - ASTEKaCEaE Aster chdensis Nees = A. ascendent Lindl. Haplopapptts njdbergU Blake - B. watsonii Gray Lactuca pulchella (Pursh) DC. = L. tatanca (L.) C. A. Mey Matricaria ntiftricarioides (Less.) Porter = ChamomilUr saaveolew (Pursh) Rydb. Solidago neniortdis Ait. = S. sparsiflora A. Gray S- occidentals (Nutt.) T. & G. = Euthamia occidentals Nutt. (Sieren 1981) Taraxacum laexAgatum (Wtlld.) DC. = T. officinale Wiggei'f! (Weber 1987)1992] Red Butte Canyon Research Natural Area 121 Vigttiem multifloru (Nutt.) Blake - Hchomeria midtiflom Nutt Coknaceae Comus stolonifcra \lichx. = Comtis seticea L. Ckui:iferae- BrASSICaCKAE Aralm divarica^Mi A. Nels. = A, ko&oeUU Homem, Rorippa islcmdiva (OecU Boj'h. = K, pahfiffiris (L,) Besser ft truncal*i (JepsJ Stuckey = fl. tenemma Greene Ojscutaceae Cuscttia campestns Yunck. = C pentagon# Engelm. GlPRRA£EAE Carex utriculata Boott =- C. rostrata Stokes Gramweae * POACL:AE(Amowl987) Agropijmn canimtm f L*) IBeauv. = Elymus trachycmdus (Link) Shinners A. dasystachyum (Hook ? Scribn. - Elymns l/m&'olatus (Scribn. & Sfri.J Gould A. intermedium (Host) Beauv. " Elymus hispulus (Opiz) Meld. A. smithii Rydb* := Elymus smiihU (Rydb.) Gould A sfriccttum (Bursh) Scribn* - Ehjims spicatus (Pursh) Gould Agrostis alba L. - A. siotomfem L. A. sorniverticillata (Forsk) C Christ, - PohjfX)gon semi- iXM'ticdhitus (Forsk;) I lylander f Aritfida bngiseta Steua. =A purpurea Nutt. Bronvus brizaefonnis Fi^ch. & Mey. - brizifonrus B. corrpnti$chrad. - B,ja])onicus Ghjccria elata (Nash) M. E, Jones = G. striata (Lam,) Hitcha HespervchloG kingii (Wats.) R\xib. = Leucopoa kingii (Wits.) W A. Weber ' KfK^eria cristata Pers. m ^ macrantha (Ledeb.) Soliiill. Onfzopsis hijnumoides (R. fit S.) Ricker = Stipe htjmenoides R. & S. Foa sartdhcrgn Vasey = P. seennda Presl (Amow 1981) Sitanion jubatum J. G Smith. misapplied to Ehjmtts chjmoides (Rafj Suezey Stipa accidentalis Thurb, = S ndsonii Sen bn JuNCaCEaE Jtmcusbalticus Willi = /. arcticwi Willd / tracyi Hvdb, = J, ensifolius Wflcst Labiatae = Lamiaceae Moldaofca parvi flora (Nutt) Britt, - Dracacephalum paroiflomm Nutt LeguminosaE = Fa&aCEaE M oracle = GannahaCeaK Hunmlus lupulus L, = H. antericanm Nutt, Onaghaceal; Epilobnim jiammdatiwx T. &G> - E, hrachtjcaqyum Presl watsonii Barbey = E. ciliatum Raf, Oenothera Iiookeri T & G, = 0, elata H.B.K. Zauchmria gamitii A, Nel s. = Z. latifolia (Horjk.) Greene OkobanckacI^\e Orobttnche califomicu Cham. & Sohlecht = O. corymbosa fBydb.) Ferris Polsmonuceae Iponwpsis aggregafa (Pvirsli) V Grant ^ Gilia aggregata (Pursh) Spreng. PGlypodiaceaf, as it occurs in Red B^ttt? Canyon, [5 novp divided into the following families !Trvon and Trvon 19S2> Dennsh'akdtiaceae. of which the genus Ptetidium is a meinber DmoPTEPJDACkAE, which includes the geriera Cystapteris and Woodsui Cystupteris frafflis (L.) Bemh. is now known to include two taxa (Lellinger 1985), of which only C. tenuis (MiehxJ Desv. occurs in Red Butte Canyon. R AN U CULAC E A E Ranuncvlm longirostiis Godron = R aquatHti U R. twticulatus Crantz = Ceratocephahis dtthveerus DC. (Weber 1987) Salicaci:ae Salix rigida MnhL - S. lutca Nutt S.VXJl^AGACEAE Lithophragma hulbifera Rydb, = L glabra Nutt Sc^opkula 111 ACEAE CaxtilUya kortardii Rydlv - C. rhexifolia Rydb. Tamaiiicaceae Tamarlx prntandra Pall. - T. ramosissima Ledeb. U MBELLIFFRAE = AFLACEAE CicuUi doaglasH (DG| Coult & Rose - C, maculaia L. Lonwtwm nuttallii (Gray) Macbr. = fcmg?/ (Wats,) Cronq.