Intermountain Forest Research Articles

基于生境质量和生态安全格局的阿勒泰地区生态保护关键区域识别

随着生态文明建设上升为国家战略，生态安全与保护修复格局的识别成为国土空间规划战略中关于生态空间保护的重要内容。为了促进区域生态系统的保护修复及有效管理，从空间尺度上对区域生态安全和修复区域的识别必不可少。利用InVEST模型的Habitat Quality模块分析了阿勒泰地区1995年、2005年和2018年的生境质量变化状况，从生态环境保护的角度出发构建区域生态安全格局，结果发现：（1）1995-2018年阿勒泰地区生境质量处于中等水平，总体呈下降趋势，说明当地生态系统有不断退化趋势；（2）以生态结构系统性和生态过程完整性为目标，通过MSPA分析结合景观连通性识别出15块生态源地，处于阿勒泰北部的山间林地和乌伦古湖区域；利用ArcGIS软件的Cost Distance工具识别出阿勒泰地区有效生态廊道38条，长约2466km，总面积约80.08km²，其中草地和林地是生态廊道穿越的重点区域；识别出最小阻力路径与生态廊道交叉处的生态节点52个，主要分布在草地和林地区域；（3）通过生境质量与最小累积阻力值识别出三类生态保护关键区域，分别为生态涵养区、生态维护区和生态保育区，结合各类生态保护关键区域的存在的生态问题提出不同的生态保护方向。研究结果为阿勒泰地区生态保护修复按照三类生态保护分区分别提出了不同的保护方向，可为阿勒泰地区国土空间生态保护修复关键区域识别和为保障区域生态系统整体保护及可持续发展政策制定提供参考。;As the construction of ecological civilization has become a national strategy, the ecological space identification has become an important part of the contents of ecological protection in territory development plan. To promote regionally ecological protection, restoration and effective management, it is necessary to analyze and identify regional ecological security and restoration patterns. In this study, Habitat Quality module of InVEST Model is used to analyze Altay Prefecture's habitat quality changes in 1995, 2005 and 2018.We constructed regionally ecological security pattern from the perspective of ecological environment protection. The following conclusions were drawn.(1) From 1995 to 2018, the habitat quality in Altay Prefecture was at a medium level and showed a decrease trend which indicated that the local ecosystem had a continuous tendency of degradation. (2) Aiming to maintain systematicness of ecological structure and the integrity of ecological process, based on the morphological spatial pattern analysis (MSPA) combined with landscape connectivity method, there were fifteen ecological sources, which located in the north intermountain forest land and around Ulungur Lake. Thirty-eight effective ecological corridors with a length of about 2466km and about 80.08km² were identified which crossed among the grassland and forest in Altay Prefecture using Cost Distance toolbox of ArcGIS software. Fifty-two ecological nodes were mainly distributed in grassland and forest, which were identified at the intersection of least resistance paths and ecological corridors. (3) According to the habitat quality and the minimum cumulative resistance value, three types of crucial areas for ecological protection were classified, namely ecological conservation area, ecological maintenance area, and ecological breeding area. The research puts forward different ecological protection directions and proposes major tasks according to ecological-environmental problems in different crucial areas for ecological protection. The research provides different directions for ecological protection and restoration. Three ecological protection zones, which can offer references for identification of crucial areas and the comprehensive ecosystem protection and formulate sustainable development policies in Altay Prefecture.

Nitrogen fluxes in Western streams

Nitrogen pollution to streams is altering the nitrogen cycling in unknown ways, causing challenges for predicting nitrogen fixation fluxes within aquatic ecosystems. Increasing nitrate pollution decreases the amount of nitrogen fixation occurring in streams. However, the relationship between stream nitrate concentration and the rate of nitrogen fixation is unknown. We predict that lower nitrate streams will have the highest rates of nitrogen fixation. Additionally, there will be much more energy produced in streams with nitrogen fixation compared to the amount required to fix the nitrogen. We estimated whole-stream gross primary production and nitrogen fixation fluxes using the diel change in dissolved nitrogen and oxygen gases compared to the expected dissolved gas saturation. Our whole-stream method is preferable to chamber estimates to understand the relationship between energy requirements for nitrogen fixation and gross primary production, but additional data is needed to distinguish between relationship types and make our measurements generalizable.
 
 Featured photo by Intermountain Forest Service, USDA Region 4 Photography on Flickr. https://flic.kr/p/jbTRUj

Big Game and Cattle Influence on Aspen Community Regeneration Following Prescribed Fire

Aspen (Populus tremuloides Michx.) is a major component of Intermountain forest ecology and relies on periodic disturbance, such as prescribed fire, to perpetuate. On the Manti-LaSal National Forest in central Utah, both big game and cattle depend on forage growing on forested lands, which has contributed to intense conflict. Understanding the effects of browsers on recently burned aspen stands is critical to managing the regeneration of these communities. This study measured the effects of cattle and big game foraging on regenerating aspen communities. Three study sites were selected from a 142-ha prescribed burn conducted in an aspen-conifer stand on the Ferron District of the Manti-LaSal National Forest in 1989. Each of the three study sites was subdivided into four areas and randomly assigned one of the following treatments: big game and cattle exclusion (No Use), big game exclusion (Cattle Use), cattle exclusion (Big Game Use), and open access (Dual Use). Vegetation was sampled in 1991–1994, 1999, and 2005. Density, biomass, height, nested frequency, and cover of aspen suckers were measured. Nested frequency and cover were measured for all other species encountered. Aspen cover, density, and biomass showed a significant year-by-treatment interaction (P < 0.05). Aspen and understory regeneration responded similarly to No Use, Cattle Use, and Big Game Use. Dual Use resulted in lower (P < 0.05) aspen regeneration and more annual, weedy species in the understory. In 2005, Dual Use aspen cover (4%) was lower (P < 0.05) than the other three treatments: Big Game Use (25%), Cattle Use (31%), and No Use (34%). Controlled burning to regenerate aspen will be most successful under light stocking rates for both big game and cattle to allow suckers to develop beyond the browse line (>2 meters).

Foliar Nutrient Characteristics of Four Conifer Species in the Interior Northwest United States

Abstract This article provides foliar nutrient concentration distributions and sample size calculations for Douglas-fir, grand fir, ponderosa pine, and lodgepole pine. Managers can obtain foliar nutrient values from their own lands and use this information to make judgments on the relative nutrient status of forest stands. Foliage was collected from unfertilized trees at 160 different research sites of the Intermountain Forest Tree Nutrition Cooperative spanning a 16 yr period from 1982 to 1997. Douglas-fir showed the lowest variation in foliar nutrient concentrations, while grand fir was the most variable of the species sampled. Nitrogen was the least variable and Mn and Mo generally the most variable elements for all species. Grand fir had much higher foliar concentrations of K and Ca than the other species. Ponderosa pine had the highest foliar N concentrations. The pines generally have lower nutrient concentrations than the firs, with the exception of Zn. Western hemlock habitat types showed lower Douglas-fir foliar Ca, Mg, and B concentrations, but higher K concentrations than other habitat type series. Douglas-fir growing on soils derived from meta-sedimentary rocks generally had lower foliar nutrient concentrations than those growing on other rock types. West. J. Appl. For. 19(1):13–24.

The effects of clearcutting and wildfire on grasshoppers and crickets (Orthoptera) in an intermountain forest ecosystem

Members of 3 families of Orthoptera (Acrididae, Gryllacrididae, Tettigoniidae) were sampled in clearcuts, burned forest, and undisturbed forest in a coniferous forest ecosystem in northern Utah, USA. Sampling was conducted during July and August, 1995 to 1997, by use of pitfall traps. The camel cricket Ceuthophilus fusiformis (Gryllacrididae: Rhaphidophorinae) was the most commonly trapped species in forested plots, where otherwise very few orthopterans were collected. Many more orthopterans were taken in clearcuts and burns and these had equal species richness and total orthopteran abundance. However, the orthopteran assemblages differed between these two treatments. Band-winged grasshoppers (Acrididae: Oedopodinae) tended to be trapped more frequently in clearcuts, especially Camnula pellucida. Burned plots provided greater numbers of Ceuthophilus fusiformis and Steiroxys pallidipalpus (Tettigoniidae: Decticinae).

Nest-Site Characteristics of White-Headed Woodpeckers

We described nest tree and site characteristics of 53 nests of the northern race of the whiteheaded woodpecker (Picoides albolarvatus albolarvatus) from the central and southern Sierra Nevada, California. We located nests in a variety of habitats and in most tree species, although 89% were in pines (Pinus spp.) and firs (Abies spp.). Nests were located near the ground (f = 3.0 m above ground level). The mean diameter breast height (dbh) of nest trees on 2 mapping grids, where some of our nests were located, did not differ (P > 0.80, P > 0.20) from random samples of snags on the corresponding grids. Most snags used for nest cavities were in a moderate state of decay. Existing snag-management policies of the U.S. Forest Service (USFS) in California will probably provide sufficient snags of the right diameter classes for whiteheaded woodpeckers, provided interactions with other cavity nesters does not limit their use of nest sites. J. WILDL. MANAGE. 53(1):50-55 Woodpeckers and other cavity-nesting birds are increasingly threatened by the reduction of snags in forest ecosystems (Vincent 1966, Short 1973). Snag requirements for many cavity-nesting species are known for particular sites but the characteristics of nests of a single species over a broad array of habitats are rarely examined. Raphael (1980:174) emphasized the need to study the characteristics of nest sites of cavitynesting birds over many forest types to reveal the range of acceptable nest conditions and the flexibility of bird preference over a wide range of snag characteristics. 1 Present address: Intermountain Forest and Range Experiment Station, 800 Block E. Beckwith, Missoula, MT 59807. This content downloaded from 207.46.13.128 on Tue, 06 Sep 2016 05:41:16 UTC All use subject to http://about.jstor.org/terms J. Wildl. Manage. 53(1):1989 WHITE-HEADED WOODPECKER NESTS * Milne and Hefl 51 The white-headed woodpecker is a common primary cavity nester in the Sierra Nevada, but little quantitative information has been published on its nest-site requirements. Our objective was to describe various characteristics of the nest sites and nest trees of this species in the Sierra Nevada and relate these characteristics to snag-management policies of the USFS in California. Numerous field assistants worked on the studies in the Sierra Nevada. We thank those who found white-headed woodpecker nests. We appreciate the constructive comments about the manuscript by M. T. Chapel, J. A. Jackson, R. W. Mannan, M. L. Morrison, M. G. Raphael, J. Verner, and 2 anonymous reviewers. We also thank K. L. Garrett and the Western Foundation of Vertebrate Zoology and J. D. Lowe and the Cornell Laboratory of Ornithology for their nest records. STUDY AREA AND METHODS We obtained nesting records from 3 USFS studies on the western slope of the central and southern Sierra Nevada, California. The studies were conducted in the summers of 1980-83 (Verner and Ritter 1983), 1983-85 (Hejl 1987), and 1985-88 (J. Verner, USFS, pers. commun.) in the Sierra National Forest, and Sequoia and Yosemite national parks. Verner and Ritter (1983), Labinger et al. (1988), Lovio et al. (1988b), and Hejl (1987) describe the study areas. Nests of white-headed woodpeckers were located incidental to the main objectives of each

Predicting Regeneration in the Grand Fir-Cedar-Hemlock Ecosystem of the Northern Rocky Mountains

Abstract Conifer establishment following regeneration treatments can be predicted in the grand fir-cedar-hemlock ecosystem of the northern Rocky Mountains. Alternative treatments can be evaluated by a model that represents regeneration establishment and early development. This model is designed to be used with the Intermountain Forest and Range Experiment Station's Prognosis Model (Stage 1973). Mathematical equations representing most harvest and site preparation methods common in the northern Rocky Mountains predict the probability of stocking, trees per acre, species composition, and tree heights between 3 to 20 years following treatment. These relations were derived from a stratified random sample of areas managed by conventional harvest and site preparation treatments. However, the analysis and modeling methods are structured to permit combinations of treatments within a stand that might differ from past practices.

Response to Tebuthiuron by Utah Juniper and Mountain Big Sagebrush Communities

The herbicide tebuthiuron was applied aerially in replicated parallel strips at rates of 0, 1.3, 2.0, and 2.7 kg/ha a.i. (active ingredient) in 40% pellets on a Utah juniper stand, and at rates of 0, 0.6, 1.0, and 1.3 kg/ha a.i. in 10% pellets on a mountain big sagebrush stand. Crown kill on Utah juniper was nearly 100% at application rates of 2.0 kg/ha or greater. Control of mountain big sagebrush was obtained at rates of 0.6 kg/ha and above. Antelope bitterbrush, hairy low rabbitbrush, and gray horsebrush responded to the herbicide similarly to Utah juniper. Rubber rabbitbrush was not controlled by tebuthiuron. Total understory production had changed little 3 years after application, although compensating decreases in production of perennial plants and increases in production of annual grasses occurred. Seldom does rangeland offer an array of plants that is ideal for a particular purpose (Stoddart et al. 1975). The species mixes are often changing as part of successional trends and such changes are often not in the direction that the land user desires. In pinyonjuniper and sagebrush ecosystems, the trend is often an increase in woody plants at the expense of herbaceous plants useable as ruminant forage. Such a trend may occur as a result of some action by man or his grazing animals or may be part of a normal progression toward a climatic climax. If a rangeland is to be held at a particular stage, periodic manipulation of vegetation may be required to reset the successional clock. Tebuthiuron (N_ES-( 1 , ldimethylethyl)-1,3,4-thiadiazol-2-yl]-N,N'dimethylurea) has shown promise for controlling many woody plants. South Texas mixed brush (Scifres et al. 1979), blackjack oak (Quercus marilandica Muenchh.) and winged elm (Ulmus alata Michx.) (Shroyer et al. 1979), sand shinnery oak (Quercus havardii Rydb.) (Pettit 1979), and various other hardwood species (Nolte et al. 1982) have been successfully controlled by tebuthiuron. Control of woody overstory species often has resulted in substantial increases in forage plants about 2 years after application of tebuthiuron (Scifres and Mutz 1978, Scifres et al. 198 1 b, Jones and Pettit 1982). Generally, the junipers have been unresponsive to tebuthiuron. Negative results have been reported on western juniper (Juniperus occidentalis Hook.) (Britton and Sneva 198 I), eastern red cedar (J. virginiana L.) (Scifres et al. 198 la), and redberry juniper (J. pinchotii Sudw.) (Ueckert and Whisenant 1982). However, tebuthiuron has been shown to be effective in controlling Utah juniper (J. osteosperma (Torr.) Little) at rates of 2.2-4.5 kg/ha (Johnsen 1977, 1979). Sand sagebrush (Artemisia filijiolia Torr.) has been effectively controlled (Jones and Pettit 1982). Control of big sagebrush has been obtained at rates of 1.1 to 2.2 kg/ha (Britton and Sneva 1983, Klauzer and Arnold 1975). Authors are supervisory range scientist and range conservationist, Shrub Sciences Laboratory, Intermountain Forest and Range Experiment Station, Provo, Utah 846Ol;and rangeconservationist, Fillmore Ranger District, Fishlake National Forest, Fillmore, Utah 8463 I. Authorsacknowledge Richard Bjerregaard and Eli Lilly and Co. for theircontributions to this research. The use of trade, firm. or corporation names in this article is for the information and convenience of the reader. Such does not constitute an official endorsement or approval by the U.S. Department of Agriculture of any product or service to the exclusion of others that mav be smtable. This article reoorts research involvinn pesticides. It does not contain recommendations for their “‘se! nor does it imply thay the uses discussed here have been registered. All uses of pestlcldes must be registered by appropriate State and/or Federal agencies before they can be recommended. Manuscript accepted April 17, 1984. 56 Cool-season herbaceous plants typical of the Intermountain region appear to be sensitive to tebuthiuron and may be strongly repressed by rates of 2 kg/ha (Britton and Sneva 1981, 1983). The pinyon-juniper zone, dominated by Utah juniper, and the sagebrush zone, dominated by big sagebrush (Artemisia tridentata Nutt.), are major plant types in the Intermountain region. Combined, they occupy 34% and 4.5% of’Utah and Nevada, respectively (USDA Forest Service 1972). These plant types, whose historic use has been dominated by the grazing of livestock, have experienced increases in amounts of woody plants and diminished amounts of herbaceous forage plants. In an effort to reverse this trend, managers have tried fire, mechanical, chemical, and biological means to manipulate vegetation. The objectives of this study were to determine the effectiveness of tebuthiuron in controlling woody plants on Utah juniper and mountain big sagebrush (Artemisia tridentata ssp. vaseyana (Rydb.) Beetle) dominated sites and evaluate response of herbaceous species.

The Adaptive Significance of Sexual Lability in Plants Using Atriplex canescens as a Principal Example

The Adaptive Significance of Sexual Lability in Plants Using Atriplex canescens as a Principal Example

Pronghorn Reactions to Winter Sheep Grazing, Plant Communities, and Topography in the Great Basin

The winter distribution of pronghorn over a 142-km2 area on the Desert Experimental Range was significantly related to sheep grazing during the current winter, presence of black sagebrush, and topographic characteristics. Even moderate sheep use during the dormant period left grazing units relatively unfavorable for pronghorn until spring regrowth-at least on ranges where key pronghorn forage plants were in short supply. Winter use areas preferred by pronghorn were above the valley bottoms in rolling to broken topography where black sagebrush communities were evident. Movement characteristics of pronghorn have allowed many of them to readily locate rested grazing units, and, therefore, avoid severe dietary competition with sheep. The Great Basin and other parts of the Intermountain West contain about 16 million ha of low-shrub cold desert. Most of these lands are publicly owned, and their primary use has traditionally been the grazing of sheep in winter and cattle in various seasons. In the last decade or so land managers have intensified efforts to consider the needs of wild animals, and require specific information to consistently make good management decisions. Information is available on pronghorn diets, water requirements, and predator losses (Beale and Holmgren 1975, Beale and Smith 1970, Beale and Smith 1973), but no intensive study has been accomplished in the Great Basin region to document the effects of livestock grazing systems on pronghorn (Antilocapra americana) populations Kindschy et al. 1978). Neither have the impact of other uses of the low-shrub desert on pronghorn been well documented for the Great Basin. A study to probe the effects of winter sheep grazing and certain environmental factors on pronghorn distribution wasconducted on the USDA Forest Service Desert Experimental Range near Milford, Utah, during the winters of 1976-81. Pronghorns thrive best on ranges with a diversity of grass-forbshrub communities (Autenrieth 1978), but are widely adaptable to different forage conditions across the total range of the species. The severity of competition between pronghorns and domestic livestock appears to vary greatly with differences in species of livestock, season of the year, and plant species available to the foraging ruminants (Salwasser 1980, Yoakum 1980). Although pronghorn habitat has mainly been manipulated by livestock grazing, many proposed energy, mineral, and defense activities threaten severe habitat disruptions. Winter ranges are often especially critical for pronghorn and are of particular concern (Kindschy et al. 1978). When the most important plants in the pronghorn's diet are a minor component of the vegetation, widespread surface disturbances or intensive sheep grazing of all available habitat could result in increased winter mortality for the pronghorn. The size and stability of pronghorn winter home ranges appear to be important in the animal's ability to adapt to newly created unfavorable habitat situations. Bayless (1969) found the pronghorn's winter home range to average 10-1 1 kM2, but one-half of the Authors are principal range scientist, Intermountain Forest and Range Experiment Station, Shrub Sciences Laboratory, Provo, Utah 84601; and wildlife biologist, Utah Division of Wildlife Resources, Cedar City, Utah 84720. Authors thank range technician John Kinney for his initiative and consistency of observation which made this study possible. Manuscript received Jan. 21, 1983. animals observed shifted home range at least once during the winter. This suggests that pronghorns may be flexible in their selection and use of wintering areas, although Howard et al. (1980) reported pronghorn avoided rough, broken terrain.

Modeling Big Sagebrush as a Fuel

Modeling Big Sagebrush as a Fuel

Black-White Ethnic Differences in Outdoor Recreation. Randel Washburne and Paul Wall. Intermountain Forest and Range Experiment Station, U.S. Department of Agriculture, Forest Service, Ogden, Utah 84401. September 1980. 13p

Black-White Ethnic Differences in Outdoor Recreation. Randel Washburne and Paul Wall. Intermountain Forest and Range Experiment Station, U.S. Department of Agriculture, Forest Service, Ogden, Utah 84401. September 1980. 13p

Early Succession following Clearcutting of Aspen Communities in Northern Utah

Changes in aspen reproduction and undergrowth production and composition were recorded over a 3-year period following clearcutting. Aspen suckers increased from 2,300 per hectare prior to cutting to a maximum of 44,000 per hectare the second post-cut year, and dropped to approximately 25,000 per hectare by the third year. Undergrowth production on the cut units increased from 1,013 kg/ha prior to cutting to 3,000 kg/ha after three growing seasons; production on the uncut control areas increased from 1,199 kg/ha to 1,539 kg/ha during this period. The significant increase in undergrowth is attributed to the reduction in competition from the removal of the aspen overstory. Clearcutting appeared to increase the proportion of shrubs in the undergrowth and decrease the proportion of forbs. A similarity index comparing the cut and uncut areas suggested that the greatest change in species composition occurred the first year after cutting, with a gradual return towards the precut conditions. The extensive aspen (Populus tremuloides) forests found at intermediate elevations in the intermountain Rocky Mountain West are highly valued multiple-use lands. They are noted for production of livestock forage, wildlife habitat, and scenic beauty, and they are a potentially valuable source of wood products. Through the process of natural plant succession many of these forests are becoming dominated by conifers, frequently within a single aspen generation. Such conversion concerns resource managers because it is usually accompanied by substantial reductions in forage and wildlife habitat. As a consequence, considerable interest has developed in periodically setting back the process of succession in order to maintain communities that are dominated by aspen. Prescribed burning and clearcutting are the 2 main management alternatives for halting succession to conifers and regenerating the aspen forest. Both of these methods involve drastic disturbance of the plant community. Intelligent use of either requires that we understand not only the effect of such disturbance upon the trees, but upon other components of the community as well. Burning is a viable alternative for rejuvenating an aspen forest where fuel conditions are amenable to fire and where the trees have little or no commercial value. Recently we published descriptions of early succession following prescribed burning of aspen communities (Bartos and Mueggler 1981). Clearcutting may be desirable either where burning is not feasible or where the value of the wood is sufficient to finance the cutting operation. Although the ability of western aspen to reproduce prolifically following clearcutting is well documented (Jones 1975, Schier 1976, Schier and Smith 1979), very little information is available regarding the changes in undergrowth likely to occur when the tree overstory is removed by clearcutting. This report describes aspen reproduction and changes in undergrowth composition and production over a 3-year period following Authors are range scientist and plant ecologist with the Intermountain Forest and Range Experiment Station, USDA Forest Service, located at the Forestry Sciences Laboratory, 860 N. 12 E. Logan, Utah, 84321. The authors wish to thank Dr. William A. Laycock for his help in the initial design of the study and in sampling in 1973. clearcutting aspen communities on the Wasatch National Forest in northern Utah.

Preference of Pygmy Rabbits (Brachylagus idahoensis) for Various Populations of Big Sagebrush (Artemisia tridentata)

Pygmy rabbits were used in feeding trials to rate preference of 15 populations of 2 subspecies of big sagebrush (A rtemisia tridentata ssp. vaseyana, A rtemisia tridentata ssp. tridentata). Monoterpenoid content of sagebrush was determined for each population in the feeding trials and related to food preference. The rabbits showed no significant preference for one A rtemisia subspecies over the other; instead, selection was made at the population level. There was no significant correlation between monoterpenoid content and dietary preference of pygmy rabbits. It has been reported by a number of researchers that wintering mule deer prefer some populations and subspecies of big sagebrush (Artemisia tridentata) over others (Plummer et al. 1968, Hanks et al. 1971, Scholl et al. 1977, McArthur et al. 1979, Welch and McArthur 1979, Welch et al. 198 1). Hanks et al. (1971) and Sheehy (1975) reported that wintering sheep expressed similar differential preferences for populations and subspecies of big sagebrush. Determining wintering mule deer or sheep preferences for populations or subspecies of big sagebrush is an arduous and timeconsuming process. Paper chromatographic and ultraviolet light tests lack the sensitivity to differentiate preference among populations in a given subspecies (Hanks et al. 1971, and Stevens and McArthur 1974). Pygmy rabbits (Brachylagus idahoensis), described by Green and Flinders (1980) as having an obligatelike relationship with big sagebrush, may be useful as a laboratory test animal in evaluating the preferences of wintering sheep and mule deer for certain sagebrush populations. Even though big sagebrush comprises 97 to 99% of the winter diet of pygmy rabbits, nothing is known about the preference of these animals for certain populations or subspecies of big sagebrush (Wilde 1978, Green and Flinders 1980, White et al. 1982). This study is the first part of a two-part project aimed at determining the usefulness of pygmy rabbits in evaluating animal preference for certain big sagebrush populations. The purpose of this study was to determine if pygmy rabbits prefer some populations of big sagebrush over others. A secondary purpose was to relate the monoterpenoid content of big sagebrush populations to possible preference differences (Barbar et al. 1969, Sheehy 1975, Scholl et al. 1977, Nagy and Regelin 1977). Methods and Materials A laboratory colony of 15 pygmy rabbits was established at Brigham Young University for use in this study. Rabbits were trapped at the U.S. Sheep Experiment Station near Dubois, Idaho. Upon arrival at the laboratory, rabbits were dusted for fleas and placed in individual pens. Every other day, rabbits received fresh sagebrush (Artemisia tridentata ssp. vaseyana and ssp. tridentata) from various locations around Provo, Utah. Guinea pig food pellets containing 17.0% crude protein, 4.0% crude fat, 12.0% crude fiber, and mineral supplement were continuously available Authors are graduate research assistant, Range Science Department, Brigham Young University, Provo, Utah 84602; chairman, Botany and Range Science Department, Brigham Young University, Provo, Utah; research plant physiologist, USDA Forest Service, Intermountain Forest and Range Experiment Station, Shrub Sciences Laboratory, Provo, Utah 84601. Manuscript received September 25, 1980. to the rabbits. Ten rabbits were selected to determine preference for various subspecies and populations of big sagebrush. Fifteen populations of big sagebrush, which included eight populations of A.t. ssp. tridentata and 7 populations of A.t. ssp. vaseyana, were selected to test for pygmy rabbit dietary preference. Subspecies were identified by morphological and chemical criteria (Stevens and McArthur 1974, McArthur et al. 1979). Selection of the populations was based on sagebrush location and on the travel time needed to collect 2 distinct populations of each of the 2

Effects of Monoterpenoid Exposure on Ability of Rumen Inocula to Digest a Set of Forages

Effects of Monoterpenoid Exposure on Ability of Rumen Inocula to Digest a Set of Forages

Recovery of Cryptogamic Soil Crusts from Grazing on Utah Winter Ranges

Range exclosures located throughout Utah in cool desert shrub communities were analyzed to determine, (1) response of cryptogamic crusts to grazing, (2) soil variables that influence development of cryptogamic crusts and (3) time needed for reestablishment of cryptogamic communities after disturbance. The amount of lichen, moss and algal cover was found to be considerably reduced by domestic grazing. Sites with moderate to high as opposed to light cryptogamic cover were characterized by significantly heavier textured soils and greater salinity. Cryptogamic cover increased from 4% to 15% during first 14-18 years of exclusion from grazing, but increased only 1% during next 20 years. Reestablishment of a cryptogamic occurs in at least 14-18 years and possibly sooner. Until recently little attention has been given soil stabilizing role of nonvascular plants (cryptogams). Studies in semidesert regions of Utah in past decade have made it increasingly clear that such plants (particularly lichens, mosses and algae) exert a significant impact on soil stability and rates of water infiltration (Anderson et al., 1982; Kleiner and Harper 1972; Kleiner and Harper 1977; Loope and Gifford 1972). The control of wind erosion is of primary importance in arid West. Many desert ranges are sparsely vegetated, resulting in large amounts of exposed soil surface. Brady (1974) suggested the presence of a stable soil crust or a rough soil surface decreased severity of wind erosion. Cryptogamic soil crusts have such a double protective influence at soil surface, since they cement soil fragments into cohesive units and produce roughened surfaces. Filamentous blue-green algae associated with soil crusts produce thick gelatinous sheaths (Durrell and Shields 1961) that render them more tolerant to desiccating conditions of desert (Fig. 1). These gelatinous sheaths coupled with intertwinning growth habit of algal filaments effectively bind surface soil particles, forming a distinct felt-like surface or shallow subsurface meshwork on many desert soils. Moss and lichen constituents of cryptogamic crusts are also important soil stabilizers. Thalli of these plants often cover much of soil surface and small ventral rhizoids penetrate surface in much same way that algal filaments do. Lichens and mosses thus become anchored on soil surface and shield soil from erosive winds and rain. The irregular soil surface caused by algal growth and lichen and/or moss thalli (Fig. 2) breaks up micro-patterns of wind flow, reduces windborne soil losses and traps drifting soil particles. The stabilizing effect of cryptogamic crusts as described here lacks quantitative analysis, thus our conclusions are based on personal Authors are, respectively, senior staff ecologist, Native Plants, Inc., Salt Lake City, Utah 84108, professor, and associate professor, botany and range science, Brigham Young University, Provo, Utah 84602. Research supported by a grant from Intermountain Forest and Range Experiment Station under a cooperative agreement supplement to 12-1 1-204-31. The collaboration of Ralph C. Homgren ofthe IFRES is gratefully acknowledged. Manuscript received June 2, 1979. Fig. 1. This filamentous blue-green alga is a common constituent of cryptogamic soil crusts. Note unusually thick sheath. experience and observations of others (Anantani and Marathe 1974, Durrell and Shields 1961, Fletcher and Martin 1948, Kleiner and Harper 1972, Kleinerand Harper 1977, Singh 1950). However, there is little question that cryptogamic communities are of importance in stabilization of many arid regions of western North American. Wind erosion on arid ranges is probably intensified by grazing during dry periods. Although hooved grazing animals are destructive to highly developed cryptogamic soils crusts, it seems possible that grazing programs can be developed that minimize damage to Fig. 2. The pinnacling of soil surface seen here isa common characteristic of more highly developed cryptogamic soil crusts. JOURNAL OF RANGE MANAGEMENT 35(3), May 1982 355 This content downloaded from 207.46.13.86 on Fri, 14 Oct 2016 04:20:13 UTC All use subject to http://about.jstor.org/terms

Summer Grazing of Sagebrush-Grass Range by Sheep

Summer Grazing of Sagebrush-Grass Range by Sheep

Monoterpenoid Content of Pygmy Rabbit Stomach Ingesta

Monoterpenoid Content of Pygmy Rabbit Stomach Ingesta

Differential Preference of Wintering Mule Deer for Accessions of Big Sagebrush and for Black Sagebrush

Free-roaming mule deer showed significant differential preference for accessions of big sagebrush (Artemisia tridentata) grown in a uniform garden. Mule deer also selectively preferred certain accessions of black sagebrush (A. nova). The role of monoterpenoids (essential or volatile oils) in determining preference among accessions and taxa of Artemisia-the sagebrushes-and the role of sagebrush as a food of starvation is discussed. Differential preference of mule deer for populations and individual plants of big sagebrush (Artemisia tridentata) has been noted by several workers (Smith 1950; Plummer et al. 1968; Winward 1970; Hanks et al. 1973; Stevens and McArthur 1974; Winward and Tisdale 1977; Willms et al. 1979; and McArthur et al. 1979). Few, however, have quantified their observations. Hanks et al. (1973), Sheehy (1975), and Scholl et al. (1977) did quantify their observed preferential differences. Of these workers, only Sheehy (1975) made statistical comparisons. He found that mule deer significantly preferred some sagebrush taxa over others. Preference of wintering mule deer for accessions of big sagebrush is one of several key characteristics being considered in our selecting and breeding program (Welch and McArthur 1979a). Therefore, we undertook this study to expand our knowledge base concerning mule deer preference for accessions of big sagebrush (A. tridentata) and for black sagebrush (A. nova) grown in a uniform garden. Materials and Methods From a uniform shrub' garden located at the Gordon Creek wildlife management area near Helper, Utah, 10 accessions of big sagebrush (Artemisia tridentata) and four accessions of black sagebrush (Artemisia nova) were chosen to determine differential preference by free-roaming, wintering mule deer. The accessions (plant material from a specific site) were transplanted onto the garden as wildlings from various Intermountain areas (Table 1). For each accession of big sagebrush, 10 plants were randomly selected. Plants were approximately the same age (planted 1968-1971). Twenty annual leaders per plant were measured to the nearest centimeter during mid-October 1977 and 1978. The leaders were selected at random over the entire crown of the plants. The 20 measurements per plant were used to arrive at a mean annual leader length (before browsing) for each plant. After the winter, and before spring growth, the plants were remeasured in the same manner as they were in October and a mean annual leader length Authors are research plant physiologist and research geneticist with the U.S. Dep. Agr. Forest Service, Intermountain Forest and Range Experiment Station, Shrub Sciences Laboratory, Provo, Utah 84601; and wildlife research biologist with the Utah Division of Wildlife Resources, Shrub Sciences Laboratory, Provo, Utah 84601. Manuscript received March 4, 1980. 'The uniform shrub garden at the Gordon Creek wildlife management area near Helper, Utah, is cooperatively maintained by the Utah State Division of Wildlife Resources (W-82-R) and the Intermountain Forest and Range Experiment Station. Table 1. Locations of 10 accessions of big sagebrush (A rtemisia tridentata) and four accessions of black sagebrush (Artemisia nova) used to determine differences in preference of wintering wild mule deer. These accessions were grown on a uniform garden near Helper, Utah. Species Subspecies Accessions County and State tridentata vaseYana Hobble Creek Utah, Utah Spanish Valley Grand, Utah Indian Peaks Beaver, Utah Milford Beaver, Utah Monticello San Juan, Utah tridentata tridentata Indianola Sanpete, Utah Loa Wayne, Utah Dove Creek Dolores, Colorado Marysvale Piute, Utah tridentata wv'omingensis Trough Springs Humboldt, Nevada nova Lund Iron, Utah Manti Sanpete, Utah Pioche Lincoln, Nevada Pine Valley Millard, Utah (after browsing) was determined. Percent used was calculated by dividing the mean leader length after browsing by the mean leader length before browsing, and then multiplied by 100. This method of measuring leader length contained a precision error term of 4%. During the first year, we had the occasion to visit the shrub garden before the start of winter (December 12, 1977). Significant browsing of the big sagebrush was noted. We remeasured the big sagebrush in the manner described above so we could determine the amount of big sagebrush eaten before winter's onslaught. For black sagebrush, 10 plants per accession were analyzed by the ocular method (National Academy of Sciences 1962) to estimate deer use. This was done only in the winter of 1978. A completely random-designed analysis of variance was used to detect significant effects due to accessions. Hartley's multiple range test was used to compare accession means (Snedecor and Cochran 1967). A t-test with paired observations was used to compare winters (Snedecor and Cochran 1967).

Early Succession in Aspen Communities following Fire in Western Wyoming

Early Succession in Aspen Communities following Fire in Western Wyoming