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...
The objectives of this investigation were two-fold: (1) to examine possible seed and cone characteristics and their usefulness as seed maturity indices, and (2) to examine the effects of artificial ripening on seed maturation and germination. Cone fresh weight, cone length, cone specific gravity, cone color, seed fresh weight, seed...
The experiment described in this paper was designed and carried out to study the ability of five provenances of white spruce of acid soil origin and five provenances of basic soil origin grown on an did and a basic soil to utilize and respond to the five macro-nutrient elements N,...
One of the largest problems facing the forester in the Pacific Northwest today is the economical, rapid rehabilitation of cut-over lands. Many of these cut-over lands are planted to Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco]. Previously, both aerial and spot seeding techniques have been evaluated for their efficiency in Douglas-fir regeneration....
An important cultural tool in the greenhouse production of tree
seedlings in the Pacific Northwest is the control of photoperiod. By
artificially lengthening the period of daily exposure to light, it is
possible to increase both the magnitude and duration of seedling
growth. By shortening the photoperiod, one can induce...
To investigate the movement of elements (N, P, k, Ca, and Mg) from the tree crowns by natural litterfall and leave wash, plots were established on six 450 year-old growth stands at the H. J. Andrews Experimental Forest. The following are the results of the data analyses. Elemental concentrations contained...
Two seed sources of Douglas-fir (Pseudotsuga menziesii
(Mirb.) Franco) seedlings were grown under several environments
in controlled growth chambers and in a natural environment. All
seedlings were grown for six months and then harvested.
One purpose of this study was to observe environmental influences
on the anatomy of the needle....
Several hundred two year old Douglas-fir (Pseudotsuga
menziesii (Mirb.) Franco) seedlings were planted in an enclosure
designed to permit control of soil moisture. The seedlings came
from five seed sources in southern Oregon and one seed source in
northwestern Oregon. Mortality terminal and lateral budburst,
and soil moisture were recorded...
The physiology of dormancy of western hemlock (Tsuga heterophylla (Raf.) Sarg.) seedlings was examined. Many areas proved to exhibit similarities to those elucidated for Douglas-fir, although significant differences were also found and necessitate the use of caution in extrapolating data from one species to the other.. Dormancy of western hemlock...
Research was conducted on the effect of field fertilization with nitrogen on existing huckleberry fields. Research was also carried out in the greenhouse to ascertain the effects of various levels of nitrogen, phosphorus, and potassium in a nutrient solution arid the effect of the pH of the solution or growth...
