Thesis (Ph. D.)--University of Washington, 1993. / Vita. Includes bibliographical references (leaves [208]-235).

Thesis (Ph. D.)--Oregon State University, 1998. / Typescript (photocopy). Includes bibliographical references (leaves 154-160). Also available on the World Wide Web.

Thesis (M.A.)--Villanova University, 2007. / Chemistry Dept. Includes bibliographical references.

Edaphic information from 168 plots in the Interior Western Hemlock (Tsuga heterophylla (Raf.) Sarg.) Dry Subzone of southeastern British Columbia was used to describe soils and to elucidate some relationships concerning soils and soil-forming factors, and soil and vegetation. Characteristics described from soil pits in each plot included thickness, depth and boundary of horizons, soil texture, structure, consistence and mottling. Color and pH were determined on 1,100 soil samples. In addition, 450 samples from 70 selected profiles were chosen for analysis of exchangeable calcium, magnesium, potassium, and sodium, adsorbed phosphate, total nitrogen, cation exchange capacity, organic carbon and calcium carbonate equivalence. Rock samples were collected and identified to aid in the determination of the nature of the parent material. Seepage water from 40 plots was analysed for calcium, magnesium and potassium content. Observations on physiography, relief, exposure, elevation, slope, drainage and erosion were recorded for each plot. Ninety Colman Fiberglas units were established in 15 plots to determine soil moisture and temperature trends. An estimation of biological activity in 15 plots was made using the loss in breaking strength of cotton duck as the criterion. Nineteen soil monoliths were prepared and over 70 color photographs taken for illustrative and comparative purposes. Soil classification generally followed current Canadian practices to the sub-group level. Certain profiles were found difficult to classify at the sub-group level. These, however, were placed in sub-groups resembling them most closely. Further subdivisions, based mainly on moisture and surface soil conditions and reflecting productivity, were formed by prefixing terms to some of the sub-group names (e.g. Dry Orthic Brown Wooded, I Normal Minimal Podzol, Moist Orthic Podzol). Of the 29 soils distinguished, the Normal Orthic Podzol, Ortstein Podzol, and I Normal Minimal Podzol were considered to represent the zonal soils of the sub-zone. These soils were oligotrophic (base saturations of B generally less than 20 per cent), and were characterized by a felty mor humus, conspicuous Ae, and a bright yellowish brown B, all of which reflected the dominant soil-forming process of the area which is podzolization. Departures from the zonal pattern, however, were numerous. Dry soils tended to have a thin F-H layer and a thin, discontinuous or absent Ae, Seepage influences ranged from an increase of exchangeable bases and humus friability in Moist Orthic and Minimal Podzols, to a build-up (over 30 cm) of organic material in Shallow and Deep Mucks. Soils such as the Dry and Normal Orthic Brown Woodeds, characterized by the absence of Ae and a base saturation generally over 50 per cent, were associated with parent materials rich in calcium especially in dry topoclimates. Where both calcareous parent material and seepage combined, soils most unlike the zonal were produced (e.g. Calcareous Duff Mull Regosol). Podzolization was less effective on steep slopes especially in warm topoclimatic situations. It reached its maximum (Ortstein Podzol) on neutral or slightly concave relief of gentle to moderate inclination, or on coarse, old, excessively drained alluvium or outwash. Brunisolic soils seldom occurred on alluvium or outwash, while strongly podzolized soils were rare in areas underlain by bedrock of the Lardeau series, Sinemurian beds and Rossland formation, or the eastern portion of the Slocan group. Seepage from pits in the vicinity of Lardeau and Slocan bedrock was higher in calcium and magnesium than seepage from other locations. Statistically significant differences occurred between sites in estimated biological activity. Moist and extremely dry sites showed high activity compared to intermediate, well-drained sites with more strongly podzolized soils. A classification of soils by moisture supply (hygrotope) and chemical characteristics (trophotope) was suggested. Associations and ecosytem types determined by an independent investigator from phytocoenotic and general environmental data corresponded fairly closely to the nature of the soil. The correspondence was, however, less apparent in moist than in dry and wet sites. / Science, Faculty of / Botany, Department of / Graduate

This thesis contributes analytical and synthetical data on the forest phytocoenoses and proposes a classification. Detailed floristical and environmental descriptions are given, also consideration of succession and life-form distribution. The following ecosystem classification is proposed: I. Dry edaphic and mesic zonal forest types of the dry subzone. 1) Pseudotsugetum menziesii a) subassoc. tsugetosum heterophyllae or the orthic Gaultheria forest type b) subassoc. legosolicum or the legosolic Gaultheria forest type c) subassoc. mahonietosum or the Gaultheria - Mahonia forest type 2) Tsugetum heterophyllae Subassoc. plagiothecietosum undulati a) var. muscosum or the orthic Plagiothecium forest type b) var. mahoniosum or the Plagiothecium - Mahonia forest type II. Dry edaphic and mesic zonal forest types of the wet subzone 3) Tsugeto – Gaultherietum a) subassoc. typicum or the orthic Vaccinium alaskaense - Gaultheria forest type b) subassoc, legosolicum or the legosolic Vaccinium alaskaense - Gaultheria forest type 4) Abieteto - Tsugetum heterophyllae a) vara clintoniosum or the Vaccinium alaskaense - Plagiothecium - Clintonia forest type b) var. acerosum circinati or the Vaccinium alaskaense - Plagiothecium - Acer circinatum forest type III. Seepage forest types 5) Thujeto - Polystichetum or the Polystichum forest type 6) Thujeto – Blechnetum a) subassoc. typicum or the orthic Blechnum forest type b) subassoc. gleysolicum or the gleysolic Blechnum forest c) subassoc. turfosum or the peaty Blechnum forest type d) subassoc. rubetosum vitifolii or the Blechnum - Rubus vitifolius forest type 7) Abieteto - Oplopanacetum or the Oplopanax - Adiantum forest type 8) Piceeto - Lysichitetum or the Vaccinium alaskaense - Lysichitum forest type IV. Moor forest types 9) Pineto - Ledetum or the Ledum forest type 10) Thujeto - Coptetum or the Lysichitum - Coptis forest type V. Flood plain forest types 11) Piceeto - Symphoricarpetum or the Symphoricarpos - Disporum forest type 12) Piceeto – Oplopanacetum a) var. populosum trichocarpae or the Ribes braeteosum - Oplopanax - Populus forest type b) var. abietosum amabilis or the Ribes bracteosum - Oplopanax - Abies amabilis forest type 13) Populeto - Loniceretum or the Lonicera - Rubus spectabilis forest type 14) Alneto - Ribisetum bracteosi or the Ribes bracteosum - Lysichitum forest type 15) Saliceto - Oenanthetum or the Lysichitum - Oenanthe forest type. The floristic structure of the phytocoenoses was studied, described and correlated with factors of the environment. Variations in the floristic and ecotopic characteristics of the units support this classification. These characteristics were used in the key proposed for identification of the forest types. Forest types as basic ecosystem units are offered for practical use. They are uniform in composition and, therefore, potentionally they require different treatments in forest management. / Science, Faculty of / Botany, Department of / Graduate

Eighty western hemlock trees, in the age range of 15 to 48 years, were selected on three Crown Zellerbach tree farms in northwestern Oregon and southwestern Washington to sample the range of variation in growth efficiency. Growth efficiency is defined as the ability of the crown to produce the maximum amount of wood in relation to its crown surface area. Selection of the trees was based on the crown index ratio (live crown length/ crown width). The objectives of the study were to estimate: 1) the range of variation in growth efficiency of individual trees, 2) how variation in growth efficiency of individual trees could be utilized to maximize volume on a unit area, and 3) the efficiency of narrow crown western hemlock trees as wood producers. Results from regression analysis showed that there was sufficient variation in growth efficiency, with a range of the standardized residuals exceeding at least ± 2.0 standard errors of the estimate for all three regression models. Based on this range it is suggested that selection of ten year basal area increment or gross stem volume for western hemlock in relation to crown surface area or sapwood basal area may be worthwhile. The significance of the variation in growth efficiency becomes apparent when the higher growth efficiency classes are selected. It is estimated that selection of the higher growth efficiency classes rather than the average may increase ten year basal area increment/hectare by 39 to 45 percent. It appears from the trees measured that there is little relationship between growth efficiency and the degree of slenderness of the crown. / Forestry, Faculty of / Unknown

Thesis (M.S.)--Oregon State University, 1993. / Typescript (photocopy). Includes bibliographical references (leaves 46-49). Also available on the World Wide Web.

Thesis (M.S.) in Forestry--University of Maine, 2008. / Includes vita. Includes bibliographical references (leaves 59-67).

Undergraduate honors paper--Mount Holyoke College, 2005. Dept. of Earth and Environment. / Includes bibliographical references (leaves 64-67).

Thesis (M.S.)--Oregon State University, 1993. / Typescript (photography). Includes bibliographical references (leaves 71-75). Also available on the World Wide Web.