Forest Vegetation of Eastern Washington and Northern Idaho Washington Agricultural Experiment Station Technical Bulletin 60 • ''\' CONTEN TS
Total Page：16
File Type：pdf, Size：1020Kb
This file was created by scanning the printed publication. Errors identified by the software have been corrected; however, some errors may remain. • • '-L.J'f!JI a fvi\E.iT GZN£Tl"S Ci5.'ff!E • Forest Vegetation of Eastern Washington and Northern Idaho Washington Agricultural Experiment Station Technical Bulletin 60 • ''\' CONTEN TS Summary ___ _________ ____________ ---------------------------- ·-----------·-------- 1 Abies lasiocarpa-M enziesia ferruginea h.t. ---------------- 44 Introduction _ ___ _______ _ 1 Tsuga mertensiana-Menziesia ferruginea h.t. 46 Objectives 1 Abies lasiocarpa-V accinium scoparium h.t. _____ -----·--- 47 Acknowledgments 2 PinttS albicaulis-Abies lasiocarpa h.t. ---------------- 48 Methods _____ ______ _ 2 Key to Coniferous Forest Habitat Types ---------------- 48 Taxonomic considerations 4 Other Vegetation Types ------------- ------·-- ---------------·--------- 50 Synecologic perspective and terminology 4 Alnus sinuata scrub . --------·---------------------------------------- 50 The physical setting 5 Parks _______ _ 50 Fire history ___ _ 6 Fen and bog -------· ________ --------------------------- ------- ----···· 50 The Habitat Types __ 7 Populus trichocarpa forest ----------------- ----------·----------- 50 The Pinus ponderosa series -----------------· __ 7 Discussion of Certain Concepts _ --·-------------·---------------- 51 Pimu ponderosa-Symphoricarpos albus h.t. _ 8 Validation of classification -------------------·- ----------------- 51 Pintts ponderosa-Physocarpm malvaceus h.t. __ __ _____ 12 Relation between undergrowth and overstory 51 Pinus ponderosa-Festttca idahoensis h.t. ___ _ 13 Relation between vegetation classification and soil classification _________________ ·-· 52 Pinus ponderosa-Agropyron spicatum h.t. _ 15 Continuity of variation -----------··--·- ---------------·--------- 52 Pinus ponderosa-Stipa comata h.t. --·---~- ____ ,::__________ 16 Principle of competitive exclusion --------------------------- 54 Pinus ponderosa-Purshia tridentata h.t. _ 18 Gradients in competitive potential ------------------ --------- 55 The Pseudotsuga menziesii series ________ ______ _ 18 Regeneration patterns ---------------------------------------------- Psettdotsuga menziesii-Symphoricarpos albttS h.t . _ 19 55 Pseudotsuga menziesii-Physocarpus malvaceus h.t. ___ _ 20 Altitude versus aspect ---------------------------- ----------------- 56 Species diversity ------------------------------------------------------- Pseudotsuga menzi,esii-Calamagrostis rubescens h.t. __ 23 57 Ecologic significance of basal area -· ·------------------------- 57 Arctostaphylos uva-ursi phase -----------·------------------ 25 Literature Cited 58 The T suga heterophylla series ____________ ____ ___ _ ·-·----------- 25 Abies grandis-Pachistima myrsinites h.t. ---------------- 26 Appendixes Thuja plicata-Pachistima myrsinites h.t. -------------------- 29 A. Tree Population Analyses ---------------- ·-- ·- --------- _ 61 Tsuga heterophyila-Pachistima myrsinites h.r. -------- 31 B. Forest U ndergrowth and Other Stand Data _ _____ 66 T huja plicata-Oplopanax horridum h.t. ------------------- 35 c. Small Mammal Components ___ ______ _ 102 T huja plicata-Athyrium filix-foemina h.t. 36 D. Soil Chemistry _ -------------------------------- _ 102 The Abies lasiocarpa series 37 E. Species Diversity ------------ ---------- 103 Abies lasiocarpa-Pachistima m yrsinites h.t. _ ------------- 40 F. Climatic Data 103 Abies lasiocarpa-Xerophyll11m tenax h.t. 42 G. Dynamic Status of Trees 104 T suga mertensiana-Xerophyllum tenax h.t. ---------------- 43 H. Basal Area __ ·------------------------------------------------------· ·-- 104 Published by Washington Agricultural Experiment Station, College of Agriculture Washington State University December, 1%8 Forest Vegetation of Eastern Washington and Northern Idaho R. DAUBENMIRE AND JEAN B. DAUBENMIRE1 SUMMARY The forest vegetation of the northern Rocky Mountains potential as to sere and climax, and is n~cognized by a dis is potentially a rather simple mosaic determined by macro tinctive combination of overstory plus understory at maturity. climate, microclimate, soil fertility and soil drainage. In Twenty-two of these units are recognized in the coniferous actuality, however, the vegetation consists mainly of a wide forest vegetation of eastern Washington and northern Idaho. variety of intergrading, disturbance-induced communities that For each, the oldest virgin stands have been sought and are difficult to treat except as developmental series related analyzed. The available d~ rn on population strucnue of trees, to specific climaxes. These relatively stable units, the asso dominance and frequency among shrubs and herbs, responses ciations, are defined primarily on the basis of the relative to disturbance, animal life, topography, soil, and total known reproductive success of trees, as this indicates which species geographic distribution are given. will become self-perpetuating dominants of the overstory. A key is presented for the identification of habitat types. Subdivisions are then based on the types of herbaceous and Consistent differences in the rate of height growth of trees, shrubby undergrowth. shapes of their growth curves, and differences in their disease Most of the land has been disturbed by lightning-induced susceptibility, along with predictable differences in their soil fires or by man's activities in the past century. Therefore, moisture regimes, all bear evidence that these landscape units the majority of forest communities represent varying stages of have fundamental ecologic significance. secondary succession progressing toward one of the climax Concepts discussed in relation to the data obtained in types, and attention is inevitably directed toward the poten clude the principle of competitive exclusion, continuity of tialities of the land. Habitat types are considered the basic variation, species diversity, and the synecologic significance ecologic subdivisions of landscapes. Each has a distinctive of basal area. INTRODUCTION Objectives very limited grazing pressure in all but the lower margin of the zonal sequence. The objectives of this study were: Remnants of primeval forest representing most of the 1. to record the structure and composition of remnants associations are still to be found. However, as more and more of virgin forest vegetation that are rapidly disappear of the land is brought under management, these stands are ing the first to suffer, for in terms of timber production they 2. to provide a classification of this vegetation on an are "overmature" and "decadent." Simple economics dictate ecosystem basis their replacement by young and vigorously growing trees. 3. to draw together the available information on climate, Thus the possibility of making such a study as this is rapidly soils and animal life that can be correlated with the I vegetation pattern 120° 4. to include enough area to provide an accurate evalu ation of geographic gradients in vegetation and prob lems of local differentiation. The core area for the study is the forest lands of Wash ington east of the San Poil and Kettle Rivers, plus Idaho north of the Salmon-Clear~ater River divide (fig. 1). But wherever an association found in this area was known to exist beyond its limits, an effort was made to include a few remote stands (as in Montana, Alberta, British Columbia, central Washington and Oregon) to obtain data showing geographic variation. This core area provides a field laboratory for synecologic study that is scarcely equalled elsewhere in the U.S.A. Al though the tree flora is not as rich as in the Appalachian region, it is richer than in most other parts of extra-tropical North America where much virgin forest may still be found. KILOM. 0 5 50 100 MILES O Other advantages result from the fairly deep soils virtually 25 50 throughout a sizeable tract of mountains, and above all the 1. Map showing area of primary study (shaded), total 1 R. Daubenmire is a Professor of Botany, Washington State extent of continental ice in the Pleistocene Epoch ( orna University. Some of the work reported here was conducted under project 1224 and Western Region project W-25. mented line), and names of counties mentioned in the text. 1 dwindling and another useful purpose, the historical, is served the closest relationships between vegetation and environment by recording the character of the primeval forest. it is desirable to stress relatively stable vegetation in which Intensified management of forest land involves planning competitive elimination has provided the clearest distinctions to accommodate diverse needs (timber, water, recreation, among the habitats in the environmental mosaic. Accordingly, livestock grazing, game, etc.). The potential of each unit stands were selected to obtain the most nearly self-reproducing of land must come under scrutiny, for efficient management populations that could be found, and to have each type of requires that each unit be used for the purpose it serves best. climax2 community represented by stands spread over a wide Natural vegetation here and elsewhere has proven of high area. To be accepted, a stand also had to have an area value for indicating land potentialities, so practical uses will 15 x 25 m in which environment, overstory, and understory certainly result from the findings in this report. all seemed as homogeneous3 as possible, with complete free Synecologic theory is still actively developing, and, un dom from ecotonal effects. Floristic