Foliage of Douglas-fir seedlings [Pseudotsuga menziesii (Mirb.) Franco] from two contrasting environments was sampled during progressive stages of two consecutive cycles of induced drought for leaf resistance, plant water potential , and abscisic acid content (ABA). One group of seedlings was placed in a controlled environment room while another group...
A systematic investigation was made of the distribution of short wave radiation within the crown of an open-grown Douglas-fir tree. The study tree was 23 years old, 14 meters tall and had a maximum crown diameter of about ten meters. Global radiation was measured every 15 cm along eight different...
This thesis is divided into three chapters. For all chapters, the experiments described deal with the responses of all or a subset
of 72 wind-pollinated Douglas-fir families from 36 different locations in southwestern Oregon. Wind-pollinated seed was collected from each of two trees at each of the 36 locations. The...
Methanolic extracts of the dormant Douglas-fir shoots (buds, leaves, and stems) were fractionated by solvent partitioning (sodium bicarbonate-diethyl ether). The acidic portion of the extract was subjected to column (Sephadex LH-2O, Silica Gel and Polyvinylpyrrolidone), preparative thick-layer and gas-liquid chromatography.
Fractions collected from chromatographic separations were collected and tested for...
From a preliminary 1969 foliar analysis, eight provenances were chosen from the sixteen included in a region-wide, reciprocal Doulgas-fir provenance study for further study of variation in foliar nutrition. In the fall of 1969 separate foliar samples were collected from ten
trees per provenance at each of ten plantations ranging...
Seasonal variations in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) leaf weight and nitrogen content were measured in Oregon's Coast and western Cascade Ranges. Current and older foliage from thinned and unthinned stands were sampled monthly from October, 1978 to September, 1979. Changes in leaf weight per unit area of foliage and...
This thesis explored the relationships between the growth of Douglas-fir seedlings and light and moisture resource availability as influenced by competitor type and density in the Oregon Coast Range. Twelve 360 m2 Nelder plots, encompassing a range of 300 to 15,000 cm2 per plant in 48 spokes, were established in...
Definitive evidence for the occurrence and seasonal variation of indole-3 -acetic acid (IAA) in shoots 0 DougLas-fir (Pseudotsuga rrienztesii (Mirb. ) Franco) was sought. Collections obtained in December and June were extracted by solvent using methanol arid diethyl ether arid by certtrtfugatiori. Extraction by ceritrifugation appeared to be twice as...
During the past 20 years, repeated thinning of a Douglas-fir forest, now 65 years old, has allowed desired limits of basal area to be maintained. In the process, the understory environment has altered sufficiently to allow Douglas-fir reproduction to establish in abundance. The forest is located on the east side...
Vegetative propagation is most effective when individuals of demonstrated superior characteristic can be propagated. For this
reason, a method for the induction of adventitious buds on cultured Douglas-fir shoot tips from 20-25 year old trees was developed. Douglas-fir shoot tips failed to survive and grow on a full strength Murashige...
When trees from 16 populations of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco. var. menziesii) were grown at ten geographically diverse locations for seven years, those from a Vancouver Island source were among the top three for height growth on nine of the ten plantations (Rowe and Ching, 1974). In contrast, growth...
A sample of 181 wind pollinated families, representative of the range of environmental conditions occupied by Douglas-fir in northern California, was used as a basis for studying variation in early height growth, phonology, and seed characteristics. Seedlings were raised at Corvallis, Oregon, in a nursery trial designed to evaluate response...
Karyotype analyses have been madeon only two on the six recognized species in the genus Pseudotsuga, Douglas-fir (P. menziesii) and bigcone Douglas-fir (P. macrocarpa). In this
study, a comparison was made between the karyotypes of Douglas-fir and Formosan Douglas-fir (P. wiloniana). The basic chromosome number of the Formosan Douglas-fir was...
The release of Douglas-fir from competition with snowbrush (Ceanothus velutinus Dougl.) has often been suggested as a way to improve conifer yield in the western Cascades. This study investigated this possibility by describing changes in the availability of water and light and the response of Douglas-fir to the changing environment,...
Douglas-fir seedlings of a single seed source were grown in a nursery under three levels of light intensity: 9, 44, and 100 percent of full light. Growth over an entire growing season was monitored in terms of proportionate distribution of dry matter to shoot and root systems. This was replicated...
The internal moisture stress of Douglas-fir was determined on foliage collected in the Siskiyou Mountains of southwestern Oregon. Internal moisture stress integrates both climatic and edaphic environmental effects as they influence a plants moisture regime. In this study two laboratory techniques were modified to permit stress measurements to be taken...
Net photosynthesis was measured for photosynthetic light efficiency and capacity on two-year-old plants from eight different seed sources in three measurement periods. The measurement periods corresponded to the physiological periods 1) prior to bud swelling, 2) after needle elongation, and 3) predormancy. Measurement period differences in both photosynthetic efficiency and...
The objectives of this investigation were to measure the seasonal and diurnal variations of starch as well as to relate these variations to growth of the trees. This study also microscopically examined the
needles to determine if starch exists in granular form in Douglas-fir. The objectives were designed to gain...
A detailed analysis was performed on the juvenile growth of six types of Douglas-fir stock under the influence of typical seral Coast Range vegetation. Objectives were to analyze competitive influences important to the growth of tree seedlings and evaluate differences between stock type characteristics and growth patterns in response to...
Nine species of ectomycorrhizal fungi were grown in liquid media over a pH range of 2-7. Species fell into five major groups: (1)
growth significantly best only at the optimal pH, (2) growth increased with increase of pH, (3) significantly best growth spans three pH units, (4) spans four pH...