This thesis investigates nonlinear climate-growth relationships and spatio-temporal variations in radial growth of Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) in coastal British Columbia (BC), Canada. The technique of Artificial Neural Network (ANN) is used to model tree-ring growth response to climatic variables. Spatial variations in radial growth are examined by comparing ring-width chronologies from three sites on southeastern Vancouver Island and nine sites in Bella Coola area of central coast BC. Radial growth in late Holocene is analyzed by examining ring-width chronologies developed from subfossil Douglas-fir at the Heal Lake site on southern Vancouver Island. A two-level linear aggregate model is proposed as an improved conceptual framework for study of tree-rings and environment. This model is useful for better understanding the interactions and transformations between different environmental factors and for unambiguous interpretation of the impact of disturbance on tree growth. The ANN technique is demonstrated to be superior to the traditional linear regression approach because of its ability to capture nonlinear and complex relationships between climatic variables and tree-ring growth. The ANN model can be used to predict tree-ring growth under given climatic conditions, and to understand climate-growth relationships by scenario analysis. Comparisons of tree-ring chronologies from three sites on southeastern Vancouver Island suggest that the climate-growth responses are generally similar. In the Bella Coola area of central coast BC, principal component analysis shows that there is common growth response throughout the nine sites of different elevations. However, there is also contrasting growth responses between sites of high and low elevations. The growing season precipitation is likely a major factor controlling radial growth of Douglas-fir on macro-regional scale in coastal BC. Five floating ring-width chronologies in the past 3rd and 4th millennia are developed using 79 subfossil Douglas-fir from the Heal Lake site on southern Vancouver Island. These chronologies show slight fluctuations and strong variations at different intervals. Notable growth anomalies occurred at about 4000 years before present, suggesting intense environmental changes, e.g., frost and droughts, at a time of suspected climate transition. The results of this study will be of use to forest management and climate studies in coastal BC. / Graduate

As a direct approach to investigate the molecular basis of embryogenesis in Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco), a cDNA library made from poly(A)⁺ RNA of developing seeds was differentially screened for clones representing transcripts abundant in the developing seeds but absent in mature seeds. Of a number of clones isolated, two groups were selected for further sequence and gene expression analysis. A group of four cDNA clones (PM2S1, PM2S2, PM2S3 and PM2S4) shared a significant nucleotide and deduced amino acid sequence similarity with each other and with gymnosperm 2S seed storage protein cDNAs. The deduced amino acid sequences had low similarity with angiosperm 2S storage proteins but contained all conserved cysteine residues in an arrangement suggestive of a structural similarity between the 2S seed storage proteins from gymnosperms and angiosperms. Northern blot analysis revealed PM2S mRNAs were present specifically in seeds and temporally during seed development. However, the relatively low abundance of PM2S3 mRNAs and the decline of PM2S2 mRNAs in megagametophyte which occurred before that of the other mRNAs suggested that their expression was regulated differentially. The accumulation of PM2S transcripts in megagametophyte started during the early embryogenesis and reached a peak before that in zygotic embryos. PM2S mRNAs were present in Douglas-fir somatic embryos at the same developmental stages as those in zygotic embryos, and ABA and osmoticum stress were necessary for the expression of PM2S genes in somatic embryos. Southern blot analysis of genomic DNA suggested that the Douglas-fir 2S seed protein genes consisted of at least two sub-families each including several gene members. A gene designated gPm2Sl was isolated and sequenced. A comparison of the upstream sequence of gPm2Sl with the promoters of known 2S storage protein genes did not reveal significant sequence similarity except the presence of RY-repeated element (GCATGC), and the frequent occurrence of ACGT-containing motifs and E-box motifs (CANNTG). The 1.2-kb gPm2Sl promoter was fused to a P-glucuronidase (uidA) reporter gene and transformed into developing Douglas-fir seeds using particle bombardment and into tobacco via Agrobacterium tumefaciens. Histochemical analysis showed that the promoter was active in both systems and the gene expression was confined to endosperm and embryos of transgenic tobacco, indicating a common seed-specific regulatory mechanism between angiosperms and conifers. Another cDNA clone, PM2.1, hybridized to a 0.5 kb transcript and was predicted to encode a metallothionein (MT)-like protein. Alignment of the PM2.1 predicted amino acid sequence with other plant MT-like gene products revealed a general paucity of Cys and Cys-Xaa-Cys sequences and the presence of serine residues within the conserved Cys-Xaa-Cys motifs in the C-terminal domain. Phylogenetic analysis showed that PM2.1 grouped with class I/type 3 MT-like genes. The PM2.1 was expressed in somatic and zygotic embryos, in megagametophyte, as well as in hormone- and metal-treated seeds and seedlings. The PM2.1 transcripts were detected in the needles of 10-week-old seedlings, but not the root tissue or mature pollen. The expression of the PM2.1 gene in embryos was dependent upon ABA and osmoticum and was differentially modulated by metals, suggesting that the PM2.1 gene product may play a role in the control of microelement availability during Douglas-fir seed development and germination. Southern blot analysis of genomic DNA suggested that the PM2.1 was encoded by a multigene family. Three genomic clones were isolated and one of these clones (gPmMTa) was cloned and sequenced. The sequence analysis of its 5'-flanking region identified a number of putative regulatory elements such as ACGT-containing motifs, metal-responsive element (TGCGCC) and ethylene-responsive elements (ATTTCAAA) which may be responsible for gene transcription. DNase I-footprinting experiments with nuclear extracts isolated from Douglas-fir megagametophyte identified two protein-protected sites, a 31-bp sequence locating in the -176/-146 region that contained two ACGT-core motifs, and a 12-bp sequence, 5'-TGCCACGGAAGG-3', of unknown function. To identify promoter regions responsible for the regulation of gPmMTa gene expression, a series of deletions in the 0.9-kb fragment of the gPmMTa promoter was fused to the uidA reporter gene and the chimeric gene constructs were assayed in Douglas-fir and transgenic tobacco. Transient expression assays in megagametophyte and zygotic embryos indicated that the sequence lying between -190 and +88 of gPmMTa was sufficient to drive the expression of the reporter gene and the 225-bp fragment (-677 to -453) contained sequences necessary for high level expression. The gPmMTa promoter was not active in the seeds of transgenic tobacco. / Graduate

The experiments discussed in this thesis are part of a continuing research program testing the influences of chemical fertilizers on the survival, growth and cone production of Douglas fir in coastal British Columbia. This study was initiated in the early spring of 1963 by the Consolidated Mining and Smelting Company of Canada Limited, Trail, B. C, and the Faculty of Forestry of the University of British Columbia. The thesis summarizes the influence of several chemical fertilizers on the survival and growth of planted Douglas fir seedlings from the beginning of the study to the present date. During the first phase of this study, the responses of planted Douglas fir to chemical fertilization have been investigated by four experiments. The first experiment, a trial of slowly soluble fertilizers, was initiated at the end of April, 1963, at three locations: U.B.C. Campus nursery, and TS 3 and TS 32b in the U.B.C. Research Forest. In a split plot design arrangement, Magamp, Urea, Aqua humus, Cxamide, Thiourea, Sludge and a bark product were dumped into or mixed with the soil in the holes made for the planting of four size classes of Douglas fir seedlings. At the end of April, 1964, the trial of slowly soluble fertilizers was repeated on the same locations. This time, the response to three Magamp particle sizes (commercially distributed Magamp, Magamp -6+8, and Magamp -8+10) as well as Sludge, Uramite and Thiourea was tested. Additional information concerning survival of planted Douglas fir seedlings was obtained from the Tahsis Logging Company at Gold River, B. C, which, in 1963, carried out a similar experiment with the same slowly soluble fertilizers. In all cases, the use of more readily soluble sources of nitrogen resulted in excessive mortality. The climate in 1963 and 1961; substantially influenced the survival and growth of the fertilized seedlings. In the second experiment, the response of Douglas fir seedlings planted in 1953, 1956 and 1959 to ammonium nitrate was investigated in the U.B.C. Forest. Nitraprills was applied randomly at six levels (0 to 800 lb. of nitrogen par acre) to a total of 360 trees. Treatments were applied in May of 1963 and 1964 at the time of flushing of vegetative buds. To date, the fertilization has improved neither height growth nor diameter increment and has had no influence on cone production. The third experiment was initiated at the end of December, 1963, in the U.B.C. Campus greenhouse. A. six-factor experiment was designed to test the responses of 2+0 planted Douglas fir seedlings to Magamp and Mitraprills. The fourth experiment was planned to compare the effects of Magamp and Nitraprills on 2+0 planted Douglas fir seedlings in the field in the U.B.C. Research Forest during the summer of 1964. The results of the third and fourth experiments have proved that the slowly soluble Magamp is more advantageous to seedlings than is the rapidly soluble Nitraprills when both are applied at the time of planting. However, these analyses have shown limited advantage to using either fertilizer during planting. The studies of these fertilizers should be continued and extended to include other sources of slowly soluble nitrogen. / Forestry, Faculty of / Graduate

The study was designed to evaluate the relative importance of certain factors influencing the strength properties of cold-pressed Douglas fir plywoods normal to glueline. In addition, estimates of strength values were also sought. Rotary-cut veneers were obtained from plywood mills; sawn veneers were prepared from lumber. A 2 x 3 x 3 factorial design was followed using veneer thicknesses of 1/10, 1/7, and 1/5 inch, and gluing pressures of 50, 200, and 350 psi. A cold-setting modified polyvinyl adhesive (Duro-Lok 50) was used in all 18 plywood blocks fabricated. From each of these, 8 tension, 4 compression and 3 glue shear specimens were prepared. Their dimensions were ½ x 1 x 4 1/2 inches, 1 x 1 x 4 1/2 inches and 1 x 3 1/4 x 3/5 inch, respectively. Plywoods of sawn veneers were only half as strong as solid wood in both compression and tension. Solid wood exceeded the compressive strength of rotary-cut veneer blocks by two, and tensile values by seven times. Stiffness of sawn veneers was twice that of rotary cut ones. The ratio of moduli of elasticity in compression to those in tension was found to approximate seven and six for the two veneer types, respectively. The difference between solid wood and sawn-veneer block strength might be attributed mainly to the influence of a suspected acid hydrolysis at the gluelines or possibly to specimen geometry. The much lower strength values of rotary-cut veneers must have resulted from the presence of lathe checks, and the lower quality of veneer surfaces. The functional dependence of all strength properties upon some independent factors, and the ranking of the latter, was established and evaluated by multiple regression analyses. The combination of the 16, 17 or 18 most important veneer and plywood variables accounted for practically all the variation, especially for rotary-cut veneers. In addition, the complete dependence of some plywood variables on independent veneer characteristics and gluing techniques were shown by regression equations. It should be noted that the three experimentally controlled factors, veneer type, veneer thickness and gluing pressure, were not always all included in the six most significant ones. The rank of variables was found to differ for each of the various strength properties observed. Analyses of variance were performed for both observed and adjusted values within each veneer type, both providing almost identical results. The high significance of veneer thickness has been shown for all strength properties, barring shear. This was explained by its strong correlation with a number of independent variables, such as glue content and specific gravity. Gluing pressure exerted a highly significant influence on all strength properties of rotary-cut veneer blocks, and in compressive stress and strain of sawn-veneer plywood construction. Its influence was attributed to the strong correlations indicated between it and other variables, for example, full compression and plastic deformation. Finally, the exploratory nature of the experiment was emphasized. / Forestry, Faculty of / Graduate

The objectives of this study were to describe the variability, to evaluate the combining ability, and to calculate the heritability values for certain characteristics of Coastal Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii. Four trees (A, B, E, and 11) were selected on the University of British Columbia Campus. Three of them were selected from the local natural population while the fourth came from an unknown provenance. The investigation of variation included phonological observations on flushing and flowering times, and quantitative descriptions of pollen, seed and cone size. A survey of Campus trees showed that Douglas-fir is extremely variable in the time of flushing and flowering, the size of pollen, seed and cones, and the total number of filled seeds. Times of flushing did not determine times of flowering. There was a strong negative correlation between pollen size and time of flowering. This suggests existence of adaptive significance to adverse climatic condition. Variation in width of the cone was greater than in cone length. Seed germination percentage appeared to be inherited on a single factor basis, and the results from Fl crosses substantiated the suggestion that tree E might possess a homozygous dominant state. Filled seeds have not been obtained from tree B when it was self-pollinated. This supports Orr-Ewing's theory, that self-sterility might be an inbreeding effect caused by the action of lethal genes, when brought together in a homozygous state. Combining ability of the four study trees was tested by a polyallel cross with all sixteen possible combinations. The cross was completed in 1962, using three different pollination methods; dry, wet and dry-wet. Mortality of conelets was lowest in the case of wet pollination. Losses were doubled with dry pollination. Of 302 seed conelets pollinated, 201 were collected and 8,004 seeds were extracted from them. The number of filled seeds per cone was lowest in the cases of self-pollination (1.91) and wind pollination (3.05). Cross pollination on the average surpassed wind pollination by 4.6 times, and the self-pollination by 7.3 times, producing 13.81 filled seeds per cone. In order to minimize and test the variability due to environmental effects, the seedlings were grown under controlled environmental conditions. Two Percival (PGC-78) units were employed, one of them simulated long-day (15 hours illumination) and the other short-day (10 hours illumination) effects for 132 days. Tree 11, which was different in origin from the local provenance trees, showed the best combining ability as a seed parent. Progeny from crosses between trees from the same populations showed smaller values compared to progenies from crosses between trees from different populations. Epicotyls, for example, were 73-78 per cent longer on seedlings from tree 11 compared to seedlings from trees B and E, when pollen from tree A was applied. Obviously, further investigation of intra-specific crosses has practical merit. Heritability values in the narrow sense were calculated for twelve different juvenile seedling characteristics, and the practical application in relation to forest tree improvement was briefly discussed. / Forestry, Faculty of / Graduate

A study was carried out to determine factors which influence the abundance of Adelges (Chermes) cooleyi Gill, on Douglas fir. This was done through the observation of populations in the field, supported by some laboratory work designed to show that certain influences are important. The work was done during the summer of 1960 in a young stand in Totem Park near Marine Drive and Agronomy Road on the U.B.C. campus, Vancouver. The following items were investigated: 1.) Inter tree differences, 2.) Intra tree variations, 3.) Population changes with time, 4.) Mortality of the insect. Abundance was affected by extrinsic influences on the trees, such as location and exposure and intrinsic factors such as time of bud opening and twig length. Within a tree the abundance of Adelges cooleyi was affected mostly by microclimatic factors, resulting in high abundance of the insect in the peripheral part of the lower crown. The average number of living insects decreased with time rectilinearly in generation 1 (Sexuparae and Progredientes) and logarithmically in generation 2 (Neosistens). A critical period during establishment of generation 2 caused the logarithmic changes. Mortality estimates by direct counts were subject to a large error because many of the dead insects fell off. / Forestry, Faculty of / Graduate

This thesis is divided in to two parts: In the first part - A Preliminary Classification of the Engelmann Spruce - Alpine Fir Forests at Bolean Lake, B. C. - some ecological concept are discussed. The forest association is defined as an ecological unit that includes the characteristics of climate, soil, topography, flora and fauna; and is recognized by its floristic structure. The area studied is described. Data were collected from selected temporary plot. Soil profile was described and samples collected. Forest mensurational data were collected on tenth-acre plots. Two forest associations can be considered established. They are: 1. Picea Engelmannii - Abies Lasiocarpa - Vaccinium membranaceum - Rubus pedatus association. (Engelmann spruce - alpine fir - black huckleberry - trailing Rubus association). Designated the VM association. 2. Picea Engelmannii - Abies lasiocarpa - Vaccinium membranaceum - Dryopteris Linnaeana association, (Engelmann spruce - alpine fir - tall blueberry - oak fern association). Designated the VO association. Four other forest associations were tentatively identified. They are described because they are of interest to foresters. In the second part - An Evaluation of Two Forest Associations in the Engelmann Spruce - Alpine Fir Forests at Bolean Lake, B.C. - forest mensurational data from the vegetational plots were compared and analysed with data from permanent sample plots established independently. Differences in average height of dominant and codominant trees, in height of average dominant tree, and in volumes between the VO and VM associations were found. These results indicate that the VO forest association has better site quality than the VM forest association. Differences were also found to composition, number of trees per acre and in the distribution of stem size, these differences indicate that the VO and VM associations will probably give different responses to silvicultural treatment. / Forestry, Faculty of / Graduate

The influence of lathe checks on shear strength of Douglas fir plywood was investigated by means of impregnating lathe checks of rotary-cut veneer to various depths using a phenol-formaldehyde resin. Comparative tensile shear strength tests were conducted on a Table Model Instron machine and photographs taken at various stages of load application to illustrate the varied manner of failure. Strength of rotary-cut veneer plywood was about 60 to 70% that of sawn veneer plywood, but after the lathe checks of core veneer were impregnated by resin there was no significant difference between them. The shear strength (Y) was found to be highly correlated with penetration depth of adhesive into lathe checks (X). The linear relationship between these factors was: Y = 228.22 + 1.28052X (SE[subscript]E = 21.82; r = 0.893). Per cent wood failure estimated by conventional methods failed to relate to shear strength. Rather, the per cent wood failure occurring within 10$ of the initiation of an annual increment was found to be a better indicator of shear strength. Use of photography helped to explain more clearly stress distribution and wood failure in the specimens. It was found that the ultimate strength was reached in conventional plywood when the lathe checks were just opening. Core-impregnated plywood was used in a test to compare the tensile shear resistance when tight-side and loose-side of veneer was next to the glue line. Neither strength nor wood failure were significantly different between the two. Tensile shear strength for plywood made of impregnated core veneer and untreated face veneer was two to three times as high as that of conventional plywood. The per cent wood failure in core veneer and shear strength varied inversely. Results obtained in this study indicated that it is feasible to develop a plywood which has shear strength as high as 500 psi while remaining economical to manufacture. / Forestry, Faculty of / Graduate

Saprophytic fungi and bacteria were recovered from healthy foliage of Douglas fir (Pseudotsuga menziesii (Mirb.) Franco). The populations of microorganisms on foliage were variable and changed through the growing season. Three species of the bacteria isolated from Douglas fir foliage were used in attempts to control the development of the rust, Melampsora medusae Thum., on Douglas fir seedlings in the greenhouse. Effective control was obtained when Bacillus cereus Frankland and Frankland and B. mycoides Flugge were applied to the seedlings in pure cultures of nutrient broth. The most effective control was obtained from the application of a mixture of these two species and a third unidentified species of Baci1lus in nutrient broth. Less effective control resulted from the application of bacteria suspended in water and cell free filtrates of the bacterial cultures. The numbers of bacteria on the foliage of Douglas fir were estimated using a modification of the soil dilution and bacterial plate count technique. The bacterial populations on foliage of Douglas fir in the greenhouse and in the field were increased by the application of bacteria in nutrient broth and sterile nutrient broth. / Science, Faculty of / Botany, Department of / Graduate

Importance of research on the provenance problem, which is basically one of seed transfer from collection site to outplanting area, is discussed with special emphasis on coastal Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii). The "Co-operative Douglas-fir provenance test," begun in 1957 and involving sixteen coastal seed sources from British Columbia, Washington and Oregon, is described in detail. Height measurements collected at the University of British Columbia Research Forest, when the trees were eleven years old, are analysed and the results are discussed. Due to site heterogeneity and young age of the Co-operative test, no significant height growth differences between provenances can be shown, although the local seed source, from the University of British Columbia Research Forest, seems to be the fastest growing and the southernmost origin, Butte Falls, the slowest of all provenances investigated. The Co-operative test is critically evaluated and specifications for further studies are recommended. / Forestry, Faculty of / Graduate