Thesis (M.S.)--Oregon State University, 1987. / Typescript (photocopy). Includes bibliographical references (leaves 63-70). Also available on the World Wide Web.

Thesis (M.S.)--Oregon State University, 1986. / Typescript (photocopy). Includes bibliographical references (leaves 109-115). Also available on the World Wide Web.

Thesis (M.S.)--Oregon State University, 1986. / Typescript (photocopy). Includes bibliographical references (leaves 50-58). Also available on the World Wide Web.

To identify genes expressed during Douglas-fir (Pseudotsuga menziesii [Mirb] Franco) germination and early seedling development, a cDNA library was constructed with mRNA pooled from 4-6-day-old seedlings. The library was then screened differentially with cDNA probes synthesized using mRNA isolated from mature seeds and 6-day-old seedlings. Partial DNA sequence analysis and predicted amino acid sequences revealed cDNA clones that encoded polypeptides with similarity to several plant proteins including: a chaperonin 606 (cpn60β), a low molecular weight heat shock protein (LMW HSP), a luminal binding protein (BiP), a type II chlorophyll a/b-binding protein (CAB), and a cysteine protease (CysP). In northern blots, each cDNA clone detected transcripts that increased during seed germination. A clone detected RNA at similar levels in both mature seeds and in 6-day-old seedlings was isolated and found to share similarity to a NADPH-cytochrome P450 reductase (CPR) (EC 1.6.2.4). The cDNA clones encoding the CysP and the CPR were selected for further sequence and gene expression analysis. The CysP cDNA consists of a 5’ untranslated region (UTR) of 153 bp followed by an open reading frame (ORF) of 1362 bp encoding a putative mature CysP flanked by N- and C-terminal propeptides. A 364 bp 3’ UTR contains multiple putative AU-rich elements that may be involved in the destabilization of transcripts. The CysP from Douglas-fir (pseudotzain) contains the same invariant amino acid residues that are involved in the catalytic reaction and make up the catalytic center of CysP from other plants and animals. Pseudotzain transcripts were most abundant in the megagametophyte (MG) after germination and were not detected in the MG or embryo during embryogenesis. Various osmotic stresses slightly enhanced pseudotzain transcript quantities during early seedling development, whereas abscisic acid, gibberellic acid and other plant growth regulators and changes in environmental conditions had little or no effect. Pseudotzain transcripts were present in different amounts in the cotyledons, root and seed coat of 10-day-old seedlings, but were most abundant in the MG, suggesting a role for this protease in storage protein mobilization. Phylogenetic analysis of mature pseudotzain groups it with other angiosperm CysP having both N- and C-terminal propeptides, suggesting a conserved function and/or targeting of this subgroup of enzymes. The CPR cDNA encodes a polypeptide of approximately 79.6 kDa. A cDNA probe detected a single transcript of 3 kb that was expressed differentially in cotyledons, radicle and MG. CPR transcript quantities were low during seed maturation, higher in mature seeds, and remained constant throughout germination and early seedling development before they declined in 14-day-old seedlings. An antiserum against a synthetic CPR-peptide was produced and western blot analysis detected a single 80 kDa polypeptide in the membrane fraction of microsomal extracts from seeds and seedlings. CPR accumulation during germination and early seedling development indicated regulation is at the transcriptional or post-transcriptional level. However, CPR activity (measured by NADPH-cytochrome-c reduction) present in the microsomes increases during stratification, germination and post-germination and decreases in 7-14-day-old seedlings. These results indicate CPR may be post-translationally activated during Douglas-fir stratification and germination. This study describes the isolation of the first cDNAs that share identity with a CysP, cpn60β, a LMW HSP, BiP and CPR (EC 1.6.2.4) from a gymnosperm. The developmental expression of these cDNAs suggests that their gene products play critical roles during the process of germination and post-germination and provides the necessary framework for future studies. / Graduate

The future demand for Canadian Douglas fir products is of particular importance because this species, although still the most important species in the forest economy of British Columbia, is being rapidly depleted. The prices of Douglas fir products are generally higher than similar products of other species. In this thesis an examination is made of the past demand for the major Douglas fir products in their various markets and projections of future demand are made to 1975. The future demand for Douglas fir is then compared to the future, potential supply of this species. It is estimated that the production of Douglas fir lumber in British Columbia in 1975 will be 6 per cent higher than in 1963. Domestic consumption of Douglas fir lumber in Canada is expected to fall by about 20 per cent by 1975, being replaced to a great extent by Eastern spruce and pine lumber. In the United Kingdom lumber market Douglas fir is being replaced by Western hemlock and cedar. If present trends continue between 1963 and 1975 exports of Douglas fir lumber to the United Kingdom will fall by 70 per cent. The main source of demand for Douglas fir lumber in 1975 will be in the United States market and it is estimated that exports of Canadian Douglas fir lumber to the United States in 1975 will be about 13 per cent above the present level. The British Columbia softwood plywood industry is a major consumer of Douglas fir logs. Douglas fir is being replaced in plywood manufacture, however, by spruce, hemlock and balsam. It is predicted that in 1975, 25 per cent of all the softwood plywood manufactured in British Columbia will be of species other than Douglas fir. This is to be compared with 9 per cent in 1963. The volume of Douglas fir peeler logs used by the British Columbia plywood industry in 1975 is expected to be twice as great as the volume used in 1962. The lumber and plywood industries are the major consumers of Douglas fir in British Columbia. Their joint demand in 1975 for this species is expected to be 2,805 MM f.b.m., that is, about 20 per cent more than in 1962. The current supply of accessible Douglas fir saw-timber is insufficient to meet the potential future demand for this species. The annual allowable cut of Douglas fir in British Columbia under sustained yield management is currently only about 36 per cent of the annual cut required to sustain the future demand for this species to 1975. It is concluded that the unique demand and supply aspects of the Douglas fir market and the high potential value of the Douglas fir resource, suggest that special attention should be given to this species in the forest management programme of the province. The value of a sustained yield policy in the case of Douglas fir is open to question and alternative methods of controlling the depletion of mature Douglas fir should be given serious consideration. Future work in this field might attempt to resolve the proportions of other species represented in trade name groupings such as "spruce" and "hemlock". Also, some of the projections of demand should be refined by more intensive analysis. / Forestry, Faculty of / Graduate

The present study deals with an extensive morphological survey of variations in Douglas-fir (Pseudotsuga menziesii (Poir.) Franco) in a cross section of its northern distribution from the Pacific Coast eastward to the Rocky Mountains. Objective was to determine whether the morphological variations were significant, and hence applicable to problems of taxonomy and ecology of Douglas-fir. Mass-collections were taken from 854 individual trees from 43 sample areas across British Columbia. The following characteristics were investigated: degree of 'bract spreading'; colour of needles and ovulate strobili; cone length and diameter; cone scale angle; number of cone scales; cone specific gravity; bract and scale length; winged seed dimensions; needle length and thickness, and some of the gross characteristics of trees such as age, height, diameter, site class, crown density, degree of branch spreading, and amount of cone production. Field investigations were supplemented by seed-fall studies and by certain nursery and greenhouse investigations (shade-light treatments, seedling comparisons). Statistical analyses employing several procedures (t-test, F-test, Chi-square test, Duncan's test, correlation and multiple regression analyses) established the basis for discussions of the differences between coastal and interior populations of Douglas-fir, as well as geographical distribution of characters and their variability within the two geographical regions and the localities sampled. Statistical parameters of several morphological characteristics have been determined, as well as their correlations with climatic and site factors. Certain observations and considerations have also been made on the taxonomy and nomenclature of Dougla fir. The following conclusions are reached: Two subspecies of Douglas-fir can be recognized, viz. 1) P. menziesii (Mirb.) Franco ssp. menziesii. Coastal Douglas-fir; and 2) P. menziesii (Mirb.) Franco ssp. glaucescens (Bailly) Schwerin, Interior or Rocky Mountain Douglas-fir. An identification key for the two subspecies and a list of synonyms are also provided. / Science, Faculty of / Botany, Department of / Graduate

This study was initiated to determine the importance of various tree characteristics and environmental factors in controlling Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) latewood formation during the five-year period 1957 to 1961. The sample included 324 mature trees representing five site types and four crown classes on the University Research Forest, Haney, B.C. Two wood "plugs" were taken from each tree at approximate breast height. The influence of seasonal variations in precipitation, temperature and frost free days on growth ring characteristics was also examined. Individuals showed significant differences in ring, earlywood and latewood zone width, and latewood percentage. Replicate samples within trees showed smaller differences. Width of earlywood and latewood increased with increasing site moisture; latewood percentage increased with dry and wet to mesic sites, suggesting some unexplained compensating mechanism. Earlywood and latewood widths increased from suppressed to dominant trees when data from all sites were grouped. No significant differences in latewood percentage were shown among crown classes, suggesting that adverse factors affecting the lower classes must influence both zones similarly. Diameter at breast height had the most influence of any tree characteristic studied, but was related to many other tree variables. Crown volume was second in importance, the order of factors being similar for all five sites. Other tree factors investigated were height, competition factor and distance to live crown. When considered in conjunction, the five tree variables accounted for about 55 per cent of the variation in ring, earlywood and latewood width. This varied somewhat with growth and site characteristics. Latewood percentage was explained to the extent of 5 per cent except on the very dry site, where 29 per cent was accounted for, mainly by crown volume and distance to live crown. Correlations with climatic factors were generally poor probably resulting from the equable climate of the area and the absence of extremes during the period studied. Both early and late season precipitation correlated positively with latewood percentage. Temperature generally showed a negative relationship with this variable. The overall dominating influence of available moisture on latewood production was shown. / Forestry, Faculty of / Graduate

The object of this work was to study the survival and growth of Douglas fir seedlings in relation to their morphological grade, and in relation to various pruning treatments. The material used consisted of two-year-old Douglas fir seedlings, grown in the campus nursery at the University of British Columbia under various organic and inorganic fertilizer treatments. These fertilizer treatments produced seedlings which varied in quality, and which were therefore suitable for use in a study of survival and growth in relation to seedling grade. Experiments were carried out under greenhouse, nursery, and field conditions. Statistical methods of analysis were used to determine the significance of the experimental results. In all cases, mortality increased directly with decrease in seedling grade. This relationship was not affected by variations of site quality in the field, the percentage of successful establishment increasing with increase in seedling grade on all sites. Shoot growth, root growth, and growth in diameter under bark were closely related to grade of seedling. Root pruning retarded bud bursting. Mortality was increased by root pruning in conjunction with top pruning, but not by root pruning alone. Shoot growth, root growth, and growth in diameter under bark were not affected by root pruning. Shoot growth, and growth in diameter under bark at the root collar were reduced by shoot and root pruning combined. / Forestry, Faculty of / Graduate

The purpose of this study was to develop a suitable pretreatment and incubation temperature for testing the germination of grand fir (Abies grandis (Dougl.) Lindl.) seed. The germination behaviour of this species varies with different seedlots of different seed years and of diverse origins. Temperature is very significant in the germination of this species. Of those incubation temperatures tested, 25° C was found to be near optimum for its germination. Stratification was shown to have a greater effect on the rate of germination than on the germinative capacity. The longer the stratification period the less sensitive the seed was to incubation temperature. The shorter stratification periods (30 and 40 days) showed little or no significant effect on the rate of germination of the relatively older seeds of the 1957 crop. Seeds dewinged by hand and cleaned by a vertical air stream gave significantly better results than those commercially processed. Results of these experiments were tabulated and analyzed. All the differences among treatments were compared and discussed in detail. A comparison of nursery germination per cent after 64 days and laboratory rate of germination was made for two seedlots and the correlations were shown. / Forestry, Faculty of / Graduate

A study of the cut-over and immature forest associations in the Douglas-fir zone on eastern Vancouver Island was carried out as a continuation of earlier investigations (Krajina and Spilsbury 1950, Krajina 1952, Szczawinski 1953, McMinn 1957) of the associations in mature stands of Douglas-fir (Pseudotsuga menziesii). Information of the environmental characteristics of the associations has been extended and their vegetational aspects in the early stages of secondary succession after logging operations are described and evaluated. It is pointed out that a set of physiographic positions is typical for each association. However, similar physiographic positions may be occupied by different associations depending upon the configuration of the soil. The soils vary with type of parent material, geographical location and physiographic position within each association. In spite of this heterogeneity it is often possible to recognize a certain association through the soil, because of common pedological characteristics related to soil genesis, moisture regime and rhizosphere characteristics. Trends and some significant site correlations are demonstrated between soil reaction and humus horizon and soil reaction and lower solum, as well as between per cent organic matter of the humus and upper solum of the association type soils. A few representative samples from soil profiles preserved as monoliths give indications of a positive trend of replaceable calcium and magnesium with the B horizons of the association type soils, increasing along the moisture gradient of the ecological series of association from dry to wet. Forest stand statistics of the old-growth as well as new stands have been compared with conventional yield table values for Douglas-fir. Typical trends reflecting site quality are shown. The pattern of forest vegetation that has been used as a key for the separation of biologically equivalent localities among virgin stands of Douglas-fir can also be utilized on cut-over land after logging operations, since the remnant vegetation largely retains its diagnostic value in regard to ecological conditions. However, the moss association loses its original floristic features and is invaded by the more dominant and aggressive elements of the related salal and sword fern associations resulting in a floristic “hybrid" between the two. This may cause difficulties in a site appraisal by purely floristic measures, and the use of the described typical physiographic positions and megascopic edaphic characteristics in combination with the residual vegetation pattern for practical purposes of site identification is recommended. Depending upon the immediate history, whether an area has been logged only, or logged and burnt, the more prevalent remnant vegetation is reduced in relative dominance, but rarely destroyed. Hence, changes among the original vegetation are largely structural rather than compositional. However, considerable compositional changes in the cut-over plant communities as a whole are brought about by the influx of the local weed vegetation, whose relative dominance and masking effect over the residual vegetation is indicative of the kind, degree and time of disturbance as well as of the associations. But, their diagnostic value in regard to ecological criteria is generally low. Therefore, if the two major groups of vegetation that comprise the cut-over plant communities — the remnant virgin vegetation and the new weed vegetation — are understood as to the relative roles they play in the early secondary succession, the population pattern of the original and more permanent vegetation can still be usefully employed as a guide to the recognition of the various forest associations after they have been logged, with or without subsequent slash burning. / Graduate and Postdoctoral Studies / Graduate