Historic, archived document Do not assume content reflects current scientific knowledge, policies, or practices. 1 AH ?. 7 United States Department of Agriculture Vegetation of Forest Service Intermountain Two Drainages in Forest and Range Experiment Station Ogden. UT 84401 Eagle Cap Wilderness, Research Paper INT-288 May 1982 Wallowa Mountains, 0regon David N. Cole ^ r^v 4* t THE AUTHOR CONTENTS Page DAVID N. COLE is research ecologist with the Wilder- ness Management Research Work Unit, located at the Introduction 1 Forestry Sciences Laboratory on the University of The Study Area 2 Montana campus at Missoula. He is on a temporary Methods 4 assignment from the University of Oregon in Eugene. Tne Community Types 5 Dr. Cole received his B.A. (1972) in geography from the Pseudotsuga menziesii/Agropyron spicatum University of California at Berkeley and his Ph.D. (1977), (PSME/AGSP) 5 also in geography, from the University of Oregon. Pseudotsuga menziesii/Physocarpus malvaceous (PSME/PHMA) 6 Pseudotsuga menziesii/Calamagrostis rubescens (PSME/CARU) 6 ncocHnv,nRF^FARPH ouivnviMnQIIMMARYi Pseudotsuga menziesii/Thalictrum occidentale (PSME/THOC) 7 A classification of vegetation is presented for part of Pseudotsuga menziesii/Berberis repens the Eagle Cap Wilderness. Compositional data and (PSME/BERE) 8 descriptions are supplied for 14 coniferous forest types Pinus flexilis (PIFL) 8 and nine other community types. An additional four Abjes grandis/Thalictrum occidentale communities are described. Under each type the author (ABGR/THOC) ' 9 discusses implications for wilderness management: Abjes lasioca rpa ,Thalictrum occidentale campsite and trail suitability, unusual problems, fire (ABLA/THOC) ' 10 management, and so on. This work should be expanded Abje$ iasiocarpa/Vaccinium membranaceum to include the entire Wallowa Mountains and incorpor- (ABLA/VAME) 12 ated into a habitat type classification while still retaining Abjes i as jocarpa/Vaccinium scoparium information on serai vegetation types. (ABLA/VASC) 13 Pinus albicaulis-Abies lasiocarpa (PIAL-ABLA) 14 Pinus contorta/Calamagrostis rubescens (PICO/CARU) 14 Pinus contorta/Vaccinium membranaceum (PICO/VAME) 15 Pinus contorta/Vaccinium scoparium (PICO/VASC) . 15 Acer g la brum (ACGL) 16 Alnus sinuata (ALSI) 17 Cercocarpus ledifolius (CELE) 17 Avalanche Slopes 17 High Elevation Grasslands 18 Phyllodoce empetriformis (PHEM) 19 Carey, spectabilis (CASP) 20 Carey, nigricans (CAN I) 20 Bare Rock and Fell-field 21 Krummholz 21 Populus tremuloides (POTR) 22 Artemisia tridentata (ARTR) 22 Subalpine Meadows 22 General Distribution of Community Types 23 Conclusions 24 Publications Cited 25 Appendixes 27 Appendix 1.— Key to Major Community Types 28 Appendix 2.— Basic Data on Community Types — 29 United States Department of Agriculture Vegetation of Forest Service Intermountain Two Drainages in Forest and Range Experiment Station Ogden, UT 84401 Eagle Cap Wilderness, Research Paper INT-288 May 1982 Wallowa Mountains, Oregon David N. Cole INTRODUCTION need to be understood, as suppression is causing un- When the National Wilderness Preservation System characteristically rapid changes in vegetation structure was established in 1964. Congress stated explicitly that and composition over large tracts of wilderness (see, for each wilderness area was to be "protected and managed example, Heinselman 1973; Vankat and Major 1978). so as to preserve its natural condition.'' In order to pro- This paper classifies and describes the vegetation of a vide this protection, the Forest Service requires that a part of the Eagle Cap Wilderness in the Wallowa Moun- wilderness management plan be developed for each area. tains of northeastern Oregon (fig. 1). Aside from several Three of the six specifications for management plans theses (Sturges 1957; Head 1959; Johnson 1959: Wood- mentioned in the Forest Service Manual (FSM 2322.1) are land 1965), little information is available on the com- to: (1) "describe the current condition of all resources and munity ecology of the Wallowa Mountains. Information biotic associations"; (2) "describe the interrelationships on vegetation is usually extrapolated from a study by of all resources, existing uses, and activities and high- Hall (1973) who worked in the neighboring Blue Moun- light unique ecological situations"; and (3) "identify prob- tains, which are topographically and geologically differ- lems associated with maintaining an enduring wilderness ent from much of the Wallowa Mountains. resource and the reasons for the problem." The primary purpose of this paper, however, is to pre- Classification and description of vegetation is an sent wilderness management implications for each vege- important step in this direction. Classification provides tation type. Each type responds uniquely to recreational an organizational framework for research and the com- use and management practices and offers distinctive rec- munication of information about different plant communi- reational opportunities. Although these implications are ties and environments. It would be particularly valuable specific to the study area, they can be cautiously applied to collect information about specific problems resulting to floristically similar and, to a lesser extent, morpho- from various types of use and organize this information logically similar types which occur elsewhere. For by vegetation type. example, in a recent study of trampling impact in the Descriptions of vegetation structure and floristic com- Tyrolean Alps, alpine meadows dominated by Carex position and their relation to selected environmental curvula were found to be resistant to damage, a response characteristics, such as elevation and aspect, will pro- quite similar to that of the morphologically similar Carex vide baseline data about "current conditions" and allow nigricans meadows in the Wallowas (personal communi- managers to evaluate and respond to future vegetational cation, Dr. G. Grabherr). changes. This information also reveals unique ecological The implications presented here should serve as a situations that might require special management strate- foundation on which an increasingly accurate and de- gies for preservation. tailed information base can be developed for the Eagle Successional relationships are an important compon- Cap Wilderness and for other areas. Information of this ent of these descriptions. Succession in response to type will ultimately lead to management that is sensitive "natural" disturbances will have to be distinguished from to inherent differences in the character of land types, the changes resulting from human activities. In particular, opportunities they provide, and the management prob- successional changes resulting from fire suppression lems they present. 1 Figure 1.— Location of the study area within the Eagle Cap Wilderness in northeastern Oregon. atures have averaged 12° F - 11 C) and 32° F (0° C) in THE STUDY AREA ( January and 46° F (8° C) and 79° F (26° C) in July. Tem- The Wallowa Mountains are the highest and most peratures at higher elevations in the mountains are un- rugged range in the Blue Mountain Province of north- doubtedly cooler. Mean annual precipitation in the moun- eastern Oregon. The Wallowas are bordered on the south tains probably varies between 20 and 80 inches (50 and and west by the basins of the Powder and Grande Ronde 200 cm). Except for a short summer dry season, precipita- Rivers. On the east they are separated from the moun- tion is distributed equitably throughout the year (U.S. tains of Idaho by the Hells Canyon of the Snake River Department of Commerce 1965). and, to the north, they drop off abruptly to the Wallowa An approximately 15 000-ha area was selected for in- River Valley and dissected plateau country. tensive study (fig. 4). The area consisted of the contigu- The Wallowa Mountains, uplifted along faults to the ous drainage basins of Hurricane Creek and the West northeast and south, have a central core of granitic Fork of the Wallowa River within the Eagle Cap Wilder- rocks. These are surrounded by folded, partially meta- 1 ness. This area was chosen because it contained a par- morphosed limestones, shales, and greenstones. Basalts ticularly wide range of rock types that outcrop over the cover extensive areas except around the granitic core of complete elevational range of the mountains and be- the range where they are only occasionally found on cause it is the most heavily used part of the wilderness some of the higher peaks (Smith and Allen 1941). The (fig. 5). The study area is unrepresentative of the range as tallest peaks exceed 9,500 feet (2 850 m) and tower more a whole in that its location to the north of the core re- than 5,000 feet (1 500 m) above the surrounding plains. sulted in particularly intensive glacial oversteepening of Extensive glaciation occurred during the Pleistocene, slopes and an underrepresentation of southerly aspects. with glaciers reaching out to the edge of the range on the In addition, basalt rocks, common elsewhere in the Wal- northeast side. Consequently, the range is characterized lowa Mountains, are rare in the study area. Observations by numerous lakes and meadows in cirque basins (fig. 2) also suggest that high-elevation species extend down- and steep, jagged ridges separating deep valleys, which ward to unusually low elevations, perhaps in response to radiate from the granitic core of the range (fig. 3). cold air drainage. The area experiences short, mild summers and long, cold winters. At Joseph, Oreg., immediately