Harvesting costs were determined for commercial thinning of young stands to
achieve vegetation and wildlife objectives. This included replicated comparisons of
thinning treatments. Treatments were defined based on residual tree stocking after
thinning. Study procedures were developed and evaluated to improve statistical
relevance. Multiple linear regression models were used to...
Modified selection thinning has been utilized by some non-industrial foresters in Douglas-fir forests of Western Oregon and Washington for at least 35 years. This silvicultural strategy has not been tested, but has often been associated with reduced volume production and other undesirable effects. It continues to be used on many...
Understanding the impact of thinning on residual stands helps forest managers achieve management objectives associated with sustainability and quality control. Stand damage control becomes more critical as thinning prescriptions in the Pacific Northwest are increasingly required for intensive management of second-growth young stands. The purpose of this study was to...
The authors varied the number of red alder retained with 300 Douglas-fir per acre on a high-quality site in coastal Oregon. Alder densities of 0, 20, 40, and 80 per acre were tested. The authors' fifth treatment eliminated nitrogen-fixing alder, but substantial nitrogen fertilizer. Treatment 6 had neither thinning nor...
The Levels-of-Growing-Stock Studies in Douglas-fir is a regional cooperative to investigate the effects of levels of growing stock on young stand growth. The Hoskins
installation, in western Oregon, was established in a dense, high site natural stand at total age 20 years. The initial thinning resulted in an immediate 131...
Logging planning and layout costs were examined for commercial thinning of 40- to 50-yr-old stands of Douglas-fir on the Willamette National Forest in the Cascade Mountains of Oregon. The study consisted of four replications of three silvicultural treatments. Thinning involved three types of logging systems: mechanized cut-to-length (a combination of...
Forest managers are beginning to take an interest in management of young Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) in Western Oregon and Washington. Studies have established the relationship between growth and levels-of-growing-stock but few have established a link to wood quality and value. This study used data collected from a long...
The objectives of this research were to study: a) the effect of thinning and treatments consisting of pruning
and multinutrient fertilization on aboveground biolnass increment, growth efficiency (GE), and foliar nutrients;
b) the influence of topoedaphic variables (soil nutrients, slope, aspect, and rock content) and foliar nutrients on both leaf...
This research examined thinning effects on stand structure and species composition in
50- to 120-year-old Douglas-fir forests. Thirty-two paired stands (thinned and unthinned)
were measured throughout western Oregon, as were 20 old-growth stands for comparison. Thinnings occurred 10 to 24 years previously and ranged in intensity from 8 to 60%...
Pollen contamination was investigated in one block (block 4) of a 10-block Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seed orchard complex in western Oregon. Blocks (25 clones each) represent different breeding zones; thus, contaminant pollen sources not only included the adjacent natural stand of Douglas-fir, but also other blocks within the...
Stem defects, including sinuosity, large branches, and the occurrence of steep-angled
branches (e.g., forks and ramicorns) can occur with high frequency in young
plantations of Coastal Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco).
The importance of including these stem defects as criteria in early selection depends, in
great part, on...
The main objective of this study was to evaluate the interaction between
herbaceous competition, fertility, and seed source on Douglas-fir survival and
growth. A secondary objective was to evaluate the effect of these various factors
on the production of lammas shoots and the selectivity of deer browse. Finally,
the role...
Transplant shock was induced by applying a range of soil water contents to unstored and cold-stored two-yearold (2+0) bareroot Douglas-fir seedlings graded by root volume. Moisture stress had the greatest influence on
morphological characteristics commonly associated with transplant shock. Terminal growth, lateral growth, stem diameter growth, and needle length increased...
The goal of this thesis was to determine the physiological mechanisms that link adverse preplanting treatments of Douglas-fir, such as exposure and root pruning, to the phenomenon of transplanting shock. The objective of experiments 1 and 2 was to measure the effect of exposure and pruning on the physiology and...
Coastal Douglas-fir (Psuedotsuga menziesii (Mirb.) Franco) 1 + 1 seedlings were fertilized with two types of fertilizers (NB4NO3+K2SO4 and (NH.4)2 SO4+KC1) at four rates (0, 80, 160, 320 kg N and K/ha) split over 3 application dates (September 19, October 13, November 1, 1996). By January 10, total Kjeldahl nitrogen...
The use of the waterborne wood preservative, ammoniacal copper zinc
arsenate (ACZA), is likely to increase in the near future because of environmental
concerns associated with oilborne preservatives. Developing an understanding of the
permanence of this preservative in wood will become important from both
environmental and performance standpoints. Conventional thinking...
Chemical stains that develop on commercial woods are
problems of great economic importance. The polyphenol
oxidases catalyze the oxidation of the phenolics that
naturally exist in plants to quinones when the cell structure is disrupted. The quinones produced are further
oxidized and polymerized to melanin, the pigment which is
responsible...
Understory conifer regeneration needs to occur beneath conifer-dominated
canopies if two-storied or uneven-aged structures are to be considered for western
Oregon Coast Range stand management. To ensure adequate numbers of seedlings
to meet stocking or habitat structure objectives, planting may be a solution. We
undertook a multi-level study to determine...
Diameter growth of Douglas-fir (Pseudotsuqa menziesii (Mirb.) Franco) estimated from increment cores was compared with that obtained from repeated measurements of tree diameter on permanent plots located in two Douglas-fir study areas in the central Coast Range of Oregon. Growth was measured for a 6-year period (1979-
1985). Diameter growth...
There is renewed interest in agroforestry as a management strategy for marginal agricultural lands in western Oregon. Silvopastoral systems combine tree and
forage production, which involve crops and practices familiar to the area. The objective of this study was to determine how
management influences the physiology and ecological interactions of...
In order to better understand the evolutionary patterns revealed by molecular
markers, we studied genetic diversity and differentiation of populations and races of
Douglas-fir using randomly amplified polymorphic DNA (RAPD) markers of nuclear and
mitochondrial origin. We conducted a range-wide survey of RAPD diversity and
differentiation, and compared RAPDs and...
The objectives of this study were to determine: 1)
differences in average wood quality and strength properties
of clear-wood specimens sampled from juvenile, transition,
and mature wood zones in Douglas-fir (Pseudotsuga menziesii
(Mirb.) Franco) trees from known forest sites; 2)
relationships among wood quality properties [specific
gravity (SG), rings per...
Overall wood density is a complex trait resulting from the interaction of three components: average earlywood density, average latewood density, and latewood proportion. In order to better understand the genetic control of wood density in juvenile Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), and to assess the utility of
information on its...
Physiology and genetics of drought hardiness were investigated in two-year-old coastal Douglas-fir seedlings from 39 full-sib families obtained from coastal British Columbia and grown at Oregon State University, Corvallis, Oregon. The seedlings were subjected to three drought treatments (control, moderate, and severe drought) in their second growing season (June through...
The goal of this study was to determine whether annual growth ring variables of
young coastal Douglas-fir (Pseudotsuga menziesii var. menziesii [Mirb.] Franco.)
growing in progeny tests are sensitive to availability of soil moisture during the growing season. If ring variables are found to respond to soil moisture deficit (SMD)...
The effect of defoliation intensity and season on Douglas-fir growth
were studied in three replications in the Siuslaw National Forest during
1988-1990. Four intensities of defoliation were applied once in either spring or
summer 1988. Stem diameter and canopy area were linearly inversely
proportional to the level of defoliation. Defoliation...
In spite of the lack of accurate information about the
treatability of western wood species with waterborne wood
preservatives, consumption of these products continues to
increase. Western wood species, notably Douglas-fir, are
notoriously difficult to treat with waterborne systems, yet
there is relatively little data on the effects of wood...
The purpose of this study was to investigate variation
in some intra-ring characteristics in juvenile and mature
wood from two Douglas-fir genetic plantations established
in 1912 by the U.S. Forest Service. The experimental
material consisted of progeny from thirty families
representing ten provenances (3 families per provenance)
grown in two...
The goal of this study was to evaluate the ability of two seedling quality evaluation methods to predict the field survival of Douglas-fir (Pseudotsuga menziesii) seedlings. The starch reserves in seedlings have been suggested as a possible predictor of seedling quality. Starch reserves have been shown to decrease during cold...
This study examined the abundance, size, growth, and age of advance regeneration
Douglas-fir, beneath an eighty year-old overstory at a single site on plots subjected to different overstory thinning treatments. Treatments consisted of keeping overstory basal area within upper and lower limits for periods of 12-17 years which, depending upon...
"In 1954, Dr. Helge Irgens-Moller initiated a rangewide collection of seed and seedlings of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco). Nearly 700 trees or stands were sampled in 10 western states, Canada, and Mexico. From 1957 to 1971, 639 of these collections were planted in the Hospital Tract Rangewide Source Archive...
Large inelastic strain occurs inside a piece of lumber during drying. The strain consists of several components such as elastic, plastic, creep, shrinkage and mechano-sorptive effect. The mechanical behavior of the whole board during drying is determined by the behavior of individual strain components and their interactions. Whereas limited investigations...
Cold hardiness and phenology are important adaptive
traits for perennial plant species in temperate climates.
Timing of growth, dormancy, and associated cold acclimation
and deacclimation represents a delicate balance between
maximizing growth under favorable conditions and minimizing
frost damage under unfavorable conditions. Geographic
patterns of genetic variation in adaptive traits,...
Aphids are a widespread family of plant pests, whose abilities to suppress shoot
and root growth are well documented for many terrestrial plants. Only a few studies have
been conducted on conifer aphids of the genus Cinara. Cinara pseudotsugae are known
to attack Douglas-fir seedlings, an important crop in the...
Two-year old Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings from two seed lots of different predicted hardiness levels were grown in two separate nurseries. Seedlings were lifted every four weeks from early October 1991 through March 1992 and exposed to controlled freezing temperatures. Fluorescence emissions of the seedlings were measured prior...
Fusarium spp. are among the most important pathogens of Douglas-fir
(Pseudotsuga menziesii) seedlings in bareroot nurseries. Currently the most effective
disease control method is soil fumigation with methyl bromide. As methyl bromide is
phased out, however, other disease management strategies may become more important.
We explored two alternative approaches to...
Five different test methods to determine the parallel-to-grain shear
strength of Douglas-fir structural lumber were compared. Four methods
assessed the shear strength of lumber sections having a full nominal two by
four inch cross-section. These were: three-point bending, four-point bending,
five-point bending, and torsion. The fifth method was the ASTM...
Basamid^R (3,5-dimethy1-1,3,5,2H-tetrahydrothiadiazine-
2-thione) is a crystalline powder used as a soil sterilant.
This fumigant acts in soil by decomposing to methylisothiocyanate
(MITC), the primary active ingredient, as well as
hydrogen sulfide, methylamine, and formaldehyde. In wood,
Basamid decomposes too slowly to be efficacious against
decay fungi unless amended with various...
Metham sodium or NaMDC is one of the four major soil
fumigants that are currently registered for controlling
internal decay of wood products in use. Fumigants are used
primarily in utility poles but are also applied to piling,
timbers and other large wood members.
NaMDC must decompose to fungitoxic compounds...
I studied species' abundances and habitat relationships
of breeding and winter birds in commercially thinned and
unthinned Douglas-fir (Pseudotsuga menziesii) stands from May
1989 to June 1991. The study was conducted in 40- to 55-year old
stands in the Central Oregon Coast Ranges and the
Tillamook State Forest. Total abundance...
Effects of bedrock water availability on growth and ecophysiology of Douglas-fir [Pseudotsuga TnenzieSii (Mirb.) Franco) and Pacific madrone (Arbutus inenziesii Pursh) were studied in southwest Oregon in 1990. Bedrock physical features, including bulk density, water holding capacity, and available water capacity, were examined at
different depths from 1.0 to 3.0...
The increased interest in red alder (Alnus rubra Bong.) management instigated research in growth and yield and stand development of red alder in pure and mixed red alder/Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stands. This study had the goa1s of evaluating the accuracy of the currently existing growth and yield tools...
The response to various levels of stand density by natural Douglas-fir regeneration, shrub and sprouting hardwood species was studied in the mixed-evergreen-forests of southwest Oregon. Partial-cut old growth (harvested 22-31 years prior) and thinned evenaged (harvested 9-17 years prior) stand types were used as surrogates for intentionally managed uneven-aged stand...
Very little is known about thinning 65- to 80- year-old noble fir dominated stands.
There is a need for such information on the Warm Springs Indian Reservation (WSIR),
Oregon where 65- to 80- year-old, high elevation, noble fir dominated stands are being managed. The objectives of this study were to...
The Regional Vegetation Management Model (RVMM) predicts the effects of associated vegetation on the growth and yield of young Douglas-fir (age [less than or equal to] 20 years) in the Pacific Northwest, and is a 'front-end' growth model for existing rotation-age growth models. Objectives of this thesis are to: (a)...
Growth phenology (i.e., timing of growth initiation and cessation) is important to adaptation. This study examined the extent of genetic control of bud and cambial phenology and their relationships with stem
growth in pole-size Douglas-fir (ages 13 to 16 years) from 60 open-pollinated families. The availability of bud phenology data...
Approximately 3-4 month-old containerized Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings (seed zone 262 and 271) were subjected to 6 moisture stress treatments (65, 53, 41, 29, 17 and 7% soil water content by volume of dry soil) starting July 4 to September 22, 1991 at Forest Research Laboratory's greenhouse at...
Our goal was to develop knowledge that will enable insertion of foreign genes into Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] trees. This required improvement of a tissue culture system for producing adventitious shoots from cotyledons, and study of factors affecting gene delivery, expression, and analysis. Administering a short-duration, concentrated liquid pulse...
Inoculation of planting holes with small amounts of soil from a mature forest and a plantation improved survival and growth of
Pseudotsuga menziesii seedlings in a degraded clear-cut in southwestern Oregon. To determine the component(s) of the
transferred soil responsible for survival and growth increases, we treated forest, plantation and...
Phaeocryptopus gaeumannii is a pathogenic fungus on Douglas-fir needles which has become a serious threat to timber production in the last decade along the Oregon coast This research was undertaken to describe the general biology and pathology of F. gaeumannii on Douglas-fir needles and how environmental variables affect fungal development....
Volatile organic emissions (VOCs) from the kiln drying
of lumber are of concern to government, research agencies,
and the forest products industry. In the Pacific
Northwest, neither the quantity of VOC emissions from kilns
drying Douglas-fir is available, nor the effects of drying
schedule and lumber-related characteristics on the
emissions....
The fungi that cause mold and stain of freshly sawn lumber result in millions of dollars in losses to the forest products industry. Stain and mold are typically prevented by either kiln drying or by application of a topical fungicide. While these treatments are effective, kiln drying is costly and...
The objectives of this research were to isolate and
determine the molecular structures of certain polyphenols
in Douglas-fir and red alder barks. The compounds of
interest in Douglas-fir were the lignans which are
eventually incorporated into the outer bark phlobaphenes.
Phlobaphenes are the red colored, alcohol soluble, water
insoluble phenolic...
Natural Douglas-fir stand development is the result of
many types of disturbance, both natural and management
induced. The magnitude and timing of these disturbances
have profound effects on the structure and composition of
both the overstory and understory plant communities. Vine
maple responds to disturbance by basal sprouting, layering,
producing...
Xylem anatomy is a strong determinant of water transport efficiency and is therefore an important component of the overall hydraulic strategy of any woody plant.
However, in addition to its role in water transport, xylem also serves in mechanical
support, and these two functions may represent conflicting design requirements. To...
Most of the methods currently used to measure root respiration introduce various disturbances which may lead to biased results, and require destruction of roots which does not permit repeated measurements of root growth and respiration. A root box method was developed for measurement of root respiration, as well as root...
To help understand the mechanisms of conifer chloroplast genome evolution, we characterized the nucleotide sequences of Douglas-fir (Pseudotsuga menziesiz) and
Monterey pine (Pinus radiata) chioroplast DNA that are associated with a length
mutation hotspot and inversion. The chloroplast DNA ofthese two conifers are
characterized by shared large inversions that are...
The major objectives of this study were: (1) to determine the extent to which southwest Oregon populations of Douglas-fir [Pseudotsuga menziesii var menziesii (Mirb.) Franco) differ in quantitative genetic structure (QGS); (2) to determine whether differences in QGS are associated with the environments from which populations originate; and (3) to...
The main objective of this thesis was to determine the influence of tree vigor on susceptibility to Armillaria root disease. First, the effect of thinning, fertilizing and pruning on tree vigor of four young Douglas-fir (Pseudo tsuga menziesii var. menziesi,) plantations was explored. Tree vigor was calculated by measuring wood...
Crown profile was modeled using a system of equations with three components.
The first equation predicts the maximum crown width of an open grown tree based on
the tree's diameter at breast height. The second equation modifies maximum crown
width to represent the largest width of the crown in stand...
Red alder (Alnus rubra Bong.) is a common associate and a potentially severe competitor of Douglas-fir (Pseudotsuga menziesii var. menziesii [Mirb.] Franco) in the Oregon Coast Range. However, because it fixes nitrogen and increases rates of soil nutrient cycling, red alder has the potential to benefit Douglas-fir. The objective of...
The purpose of this study was to assess how growth of young to mature Douglas-fir
(Pseudotsuga menziesii (Mirb.) Franco) and western hemlock (Tsuga heterophylla (Raf.) Sar.)
in mixed stands was influenced by the presence of residual trees. Fourteen paired plots with
and without residual trees were examined in a retrospective...
This study examined the relationships between the frequency of occurrence and severity of Douglas-fir dwarf mistletoe (Arceuthobium douglasii Engelmann), environmental and stand conditions, and plant communities in the Southern Oregon Cascade Mountain Province. Data for the study was collected from the same ecology plots that were previously used to define...
I developed a conceptual model of Douglas-fir bark beetle dynamics and associated host mortality across spatial and temporal scales. I proposed that a hierarchy of factors influence host resistance to attack at different spatial scales. I then tested this model by measuring the association between the occurrence of beetle-kill and...
Reprinted August 1995. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
This publication focuses on even aged, fully stocked, Douglas-fir
stands. Because of fire history and past harvesting patterns, such stands
dominate west of the Cascades throughout much of Oregon, Washington,
and northern California. Stand volumes and dollar values will be
different for other species.
It is difficult to treat the heartwood of many wood species with liquid preservatives using conventional liquid processes. Supercritical fluids (SCF) used as carriers of preservatives to impregnate refractory wood species may be an attractive alternative to conventional liquid carriers. While SCF impregnation has many potential advantages, some wood species...
Over the past 30 years, Christmas trees have become an intensively managed horticultural crop. During this period, higher standards and increasing competition have given the edge to growers who are progressive and highly motivated. Whether you’re a large or small producer, your trees must have consistently high quality for successful...
There has been an increased interest in the
quantification of pattern in ecological systems over the past
years. This interest is motivated by the desire to construct
valid models which extend across many scales. Spatial methods
must quantify pattern, discriminate types of pattern, and
relate hierarchical phenomena across scales. Wavelet...
To understand the effect of human-induced stresses on forests, there is a need for a method to separate effects of imposed stress from effects of natural climate stress. I developed an approach to predict forest response to climate stress using as indicators stable carbon isotopes in tree foliage and growth-rings....
Douglas-fir and grand fir seedling establishment and plant community regeneration were examined in a western Oregon forest following harvest in three
different silvicultural systems: clearcut, two-story and patchcut. The two-story system
consisted of removing all but 10 to 12 trees per acre. The patchcut system consisted of
harvesting 1/2 acre...
Index selection provides an efficient means of conducting selection on multiple traits by combining information on economic value,
heritability, and the genetic and phenotypic correlations between traits to improve overall merit. The use of this method in forestry has been hampered by the lack of knowledge of the relative importance...
Hann and Scrivani (1987) developed dominant height growth equations for Douglas- fir in southwest Oregon using stem analysis data sets with an upper age of approximately 125 years at breast height. The objective of this study was to determine whether these equations could be extrapolated for ages of 250 years...
Disease is often overlooked as a natural disturbance agent in plant communities. This study examines what effects, if any, a disease-mediated disturbance has on the plant community as a whole in old-growth and mature forests of western Oregon. Phellinus weirii (Murrill) Gilbertson (Family: Hymenochaetaceae) is a native root-rotting pathogen that...
Cones of Douglas-fir and ponderosa pine with extensive mold on external portions of scales were sampled for presence of fungi potentially pathogenic to conifer seedlings in nurseries. The major colonizers of cone scales and external seedcoats for both conifer species were Trichoderma spp. Penicillium spp. were also very common. The...
This annotated bibliography was compiled to provide a comprehensive list of sources on the ecological factors that affect forest regeneration. Abstracts from 494 publications are indexed by author, species, and subject, and are arranged into 4 major sections. Topics include the effects of biotic factors, abiotic factors, and stand and...
Western redcedar, western hemlock, and Douglas-fir seedlings were transplanted into pots in one of two soils representative of high and low levels of available NO3 (and total N). The soils were collected from sites at Cascade Head (Oregon Coast) and Wind River (Washington Cascades). Whole plant and component relative dry...
Disaggregative and individual-tree/distance-independent modeling methods are
compared and contrasted. Differences between the two are related to differences in functional
and apparent resolution and may be illustrated using aggregation theory. When considering
models of different levels of resolution describing a given phenomenon, invariance with respect
to the aggregation implied (symmetry) may...
Equations for predicting diameter growth are an essential component of single-tree growth and yield models (Munro 1974). Diameter
growth predictions are used to characterize individual-tree development and to project the growth of stand basal area and volume. Both diameter growth and basal area growth have been used as the dependent...
Annosus root disease (Heterobasidion annosum (Fr.) Bref.) is causing notable conifer
mortality in grand fir habitat types in central Idaho. The most significant mortality is occurring in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco.) trees of all age classes. This project was designed to study some aspects of the general biology of...
Previous studies of bird communities in the mid-Willamette Valley, Oregon, indicated that Oregon white oak (Ouercus garryana) stands supported more cavity-using bird
species than sympatric stands of Douglas-fir (Pseudotsuga menziesii). Mature Oregon oak stands are being harvested and few are regenerating. I compared cavity availability for hole-using fauna among 10...
Information about forest substrate respiration, nitrogenase activity and
mineralizable nitrogen may be incorporated into carbon and nitrogen budgets that comprise an important element of forest management planning. In this study, substrate respiration, nitrogenase activity and mineralizable nitrogen were measured in two western Oregon Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] stands within...
After three-quarters of a century of introduction of 152 conifer and broadleaf species,
no promising candidate exotic was found for the Douglas-fir region. Growth curves
spanning 50 years or longer are figured for many species. Firs, pines, larches, spruces,
hemlocks, and cedars originating in northwestern North America had superior growth...