Published March 1974. A more recent revision exists. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Two objectives of this research were to identify fungi which are
mycorrhizal with western hemlock and to examine the ecology of hemlock
mycorrhizal fungi indigenous to outplanting sites. Another objective
was to evaluate the effectiveness of mycorrhizal inoculation in
improving the performance of outplanted hemlock seedlings.
A list of over...
Using clones to regenerate a species new to clonal reforestation presents the forest manager with many problems. A number of interrelated and interdependent research and development activites are needed to answer these technical questions. Network diagraming was used for scheduling research activities and for indicating interdependencies among activities. The resultant...
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...
The need for increased efficiency in regeneration of western hemlock (Tsuga heterophylla (Raf.) Sarg.) requires greater understanding of seedling physiology. Experiments examined western hemlock seedling growth responses to in-bed root pruning, and pruning of shoots or roots prior to transplanting. Measurement of plant
moisture stress (PMS) after physical root disturbance,...
A range-wide sample of 221 provenances of western hemlock (Tsuga heterophylla (Raf.) Sarg.) showed much variation in several characteristics. Variation in seed weight was significant, but not correlated with seed source latitude, elevation, or distance from the ocean. Variation in the frequency of 4-cotyledon seedlings was significant at
regional, provenance,...
The capacity for root growth and concentration of indole-3-acetic acid and abscisic acid in the roots of western hemlock seedlings was investigated. The root regenerating capacity (RRC) was defined as the increase in root length, greater than 5 mm, following a 28-day test period. RRC measurements over a two-year period...
Hemlock dwarf mistletoe (Arceuthobium tsugense subsp. tsugense) is an arboreal, hemiparasitic plant that principally parasitizes western hemlock (Tsuga heterophylla). Hemlock dwarf mistletoe exerts a profound influence on infected trees that can drastically change the structure of the tree crown due to reduced growth, top dieback, branch deformation and death, resulting...
The advantages of high-temperature drying are faster drying, reduced inventory, reduced energy requirements, and reduced equilibrium moisture content. However the disadvantages are higher initial costs of the kiln, greater power needs, knot dropout, and reduction in some strength properties. The latter was the subject of this study. Three hundred pieces...
A decreasing rate of flow was observed (after sufficient air and particulate matter were removed from the wood and water) under steady-state conditions for green western hemlock sapwood. The decrease is theorized to be due to viscoelastic behavior of pit membranes. An unsteady-state procedure for determining longitudinal liquid permeability of...
Young western hemlock stands in the Coast Range of Oregon will
contribute to the commercial timber supply of the region in the
future, the extent of the contribution depending on environmental
and cultural factors. The relative diameter and volume growth of
crop-trees in the stands will be increased substantially by...
Variability in wood properties causes boards within a stack of lumber to
dry at different rates and reach different moisture content levels after drying is
completed. The consequence is that the boards will have properties that differ from
ones that were intended to be achieved by the drying process.
The...
The response of western hemlock (Tsuga heterophylla [Raf.] Sarg.) to two methods of site preparation for planting was compared. One site was cleared of mature brush by the "brown-crush-and-burn" method. The other was partially cleared by spraying with herbicides. Seedlings lifted and planted in December, January, February, and April were...