Using ¹³C cross polarization magic angle spinning nuclear magnetic resonance techniques on 5 species of dead trees from the northwest (western hemlock, Douglas fir, Sitka spruce, lodgepole pine and ponderosa pine) I tracked the lignin and cellulose content over a 22 to 36 year period in order to determine the...
Many mycorrhizosphere microorganisms can produce
plant growth regulating compounds in vitro. Plant growth
regulating compounds are known to mediate root growth and
development. In reforestation practices, conifer tree
seedling growth and survival are linked to rapid root
growth and development after outplanting. Multifactorial
experiments were conducted to document variations in...
Previous studies have indicated that roots from five tree species (Picea sitchensis, Tsuga heterophylla, Pseudotsuga menziesii, Pinus ponderosa, and Pinus contorta) decompose at different rates across an environmental gradient in Oregon. Measurements of wood chemistry from each tree species as well as moisture and
temperature from each location do not...
White and grand fir are both valuable components of the mixed-conifer stand structure managed for late-successional reserves in central Oregon. However, they are often short-lived species because of high susceptibility to root diseases, defoliating insects, bark beetles, and wildfire. This study focuses on the effects of root diseases caused by...
Controls of substrate quality, temperature, and moisture on woody root decomposition in the Pacific Northwest were explored using chronosequences, time series, laboratory incubations, and simulation modeling approaches at three sites: Cascade Head
(CAH), H. J. Andrews (HJA), and Pringle Falls Experimental Forests (PRF). In the chronosequence study, a structural component-oriented...
Methods used to establish permanent plots in precommercially thinned and unthinned stands to monitor root disease development are described. Plots were established in 22 Armillaria-infested stands in northern Idaho and western Montana. The proportion of trees dead and infected was significantly higher for planted than for natural regeneration at the...
Published March 1925. 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
Investigations of containerized conifer seedling root diseases at the Champion Timberlands Nursery revealed that Fusarium oxysporum was most commonly isolated from seed, seedling roots, and styroblock containers. Amount of seed infection varied widely among the seedlots tested, but was usually below 5 percent. Runningwater rinses did not reduce amounts of...
Pseudotsuga menziesii dominates the forests of the Pacific Northwest.
But though it is dominat, Tsuaa heteroohylla or Abies amabilis
is usually climax. Many researchers have studied Pseudotsuga on the
widespread mesic sites where it is seral, but few have examined the
relatively rare ecosystems in which Pseudotsuga or its associate...
It’s little wonder that people are confused by tree names. Foresters
and lay people often name a tree based on its physical appearance, the
wood products industry may call the tree by another name based on the
characteristics of the wood, and botanists name a tree based on its
anatomical...
DNA markers that detect polymorphisms within and between two biological species of the coniferous laminated-root-rot fungus Phellinus weirii were developed and used to
measure the amount and distribution of genetic variation. In a preliminary survey, total cellular DNA from 3 Douglas-fir-type isolates and 3 cedar-type isolates was digested with 12...
Investigations of containerized western white pine, western larch, and Douglas-fir seedlings at the Western Forest Systems Nursery in Lewiston, Idaho, revealed that many seedlings were colonized with Fusarium oxysporum although they lacked severe disease symptoms. White pine seedlings were also infected with Pythium spp., probably as a result of sowing...
A survey for incidence and distribution of root diseases was conducted on the Kootenai National Forest using timber inventory subcompartments as primary sample units. Root diseases were located within 23 of 75 sampled subcompartments. At least 1.1 percent of the commercial forest lands within the Forest are infested with root...
This study was started in 1947 to investigate the value of various types and quantities of seed source in the establishment of reproduction on cutover land, and to determine the apparent effects of various man-made and natural factors upon the rate of restocking. The man-made and natural factors to be...
Evaluation of meta-sedimentary bedrock as a source of stored water available
to plants in a mediterranean climate is presented based on: root length distribution
(RLD), root morphology, rock water holding capacity and seasonal pattern of water
depletion. Studies were performed in southwestern Oregon under young stands of
whiteleaf manzanita, ponderosa...
Published October 1946. 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
Published December 1941. 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
In the past decade, Oregon produced on average 344,000 tons of sweet corn for processing on 43,000 acres annually, which ranked the state fourth nationally.
Most Oregon sweet corn is grown in the Willamette Valley where, along with green beans, it is a mainstay of the processed vegetable industry. However,...
A root disease evaluation was completed for the Ducharme logging unit near the southeast corner of Flathead Lake. Extensive root disease was found on Douglas-fir throughout the unit. The major pathogen on the site was Armillaria meilea. Black stain (Verticicladiella sp.) was isolated from one tree which was also infected...
The use of fungicides for the control of foot rot of winter
wheat, caused by Pseudocercosporella herpotrichoides (Fron) Dei.,
requires a forecast of disease risk to optimize this management
practice ecologically and economically. Foot rot occurs in both
the mild, wet (100+ cm, ppt./year) annual cropped areas in western
Oregon,...
An impact survey to determine extent and distribution of root disease centers was completed for the Nezperce National Forest, Idaho, in 1980. Lowlevel
color infrared photography was used to delineate root disease centers
within National Forest inventory subcompartments. Suspected root disease
centers were ground checked to determine associated fungi and...
Discusses options for managing major insect pests and diseases of conifers in Oregon forests: bark beetles, wood borers, and ambrosia beetles; defoliators; aphids, adelgids, and scale insects; terminal and branch insects and pitch moths; root diseases; stem decays; foliage diseases; canker diseases and canker-causing rust diseases; and mistletoes. Extensive references...
An analysis of lumber prices provided regressions for price trends during the period 1971-95 for composite lumber grades of major timber species found in the Pacific Northwest west of the crest of the Cascade Range. The analysis included data for coastal Douglas-fir and hem-fir lumber; coastal and inland Pacific Northwest...
The ability of controlled livestock grazing, in
combination with seeding of palatable forages, to reduce
understory competition and enhance conifer
establishment, was evaluated during 1985 and 1986, on
two adjacent sites in southwestern Oregon. In 1984,
Site 1 was clearcut and broadcast burned to remove
slash, and Site 2 was...
Successful reforestation of your harvested timberland is more than just
planting a few trees and hoping they will grow. To ensure success,
you first must answer several key questions:
• What species should I plant?
• What kind of seedlings should I select?
• How can I tell whether their...
This thesis presents methods for obtaining asymptotically efficient and consistent parameters and variance estimates for simultaneous equations in a forest growth modelling context. Ordinary Least Squares (OLS), Seemingly Unrelated Regressions (SUR), Two-Stage Least Squares (2SLS) and Three- Stage Least Squares (3SLS) are presented for linear models. The variables, model types...
This thesis consists of three parts: 1) a field case study involving tree growth, moisture stress, and foliar nitrogen response
to sheep-grazed pasture treatments; 2) a shadehouse (potted-plant) study of simulated grazing effects on tree growth and moisture use; and 3) a summary, synthesizing results of the field and shadehouse...
Equations for predicting the 5-yr height growth rate of a tree are presented for six conifer species from southwest Oregon. Equations for the combination of undamaged and damaged trees were estimated with weighted nonlinear regression techniques. These equations are being incorporated into the new southwest Oregon version of ORGANON, a...
The effect of serial (multiple-year) organic matter (OM) amendment on soil properties has been described in some cropping systems, although less is known about the effect of serially amended field soils on soil-borne plant diseases. The objectives of this study were to describe the effects of the third and fourth...
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...
Voles, or meadow mice as they’re commonly called, can cause significant economic damage to conifer seedlings on reforestation sites and Christmas tree plantations.
Published September 1939. 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
Root disease fungi attack and destroy the tree’s root system, resulting in growth loss, decay, death, or wind throw of infected trees. Trees with root disease also are more susceptible to pests, especially bark beetles. On the other hand, root diseases are a component of the forest ecosystem and play...
To study the combined effects of seedling quality and fertilization at the time of planting, three experiments were established in western Oregon during the winter of 2000. The first experiment investigated the effect of preplanting rootvolume and fertilization rate on the field performance of 1+1 Douglas-fir seedlings during two growing...
Southwest Oregon presents an environment of hot dry summers, cool moist winters, and rocky, shallow soils. The establishment of conifer plantations in this region presents challenging problems for initial seedling survival and subsequent growth. Three areas of concern include early conifer growth after seedling establishment, growth of competing hardwoods within...
Weed control in Pacific Northwest forests has been criticized for its potential impact on biodiversity. Changes were evaluated in conifer growth, diversity of vegetation in situ and of recruiting plants through different regeneration mechanisms after applying temporally-varied weed control by herbicide treatments based on the critical period concept. Conifer size...
Published September 1983. 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
Published May 1984. 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
Forest managers of public lands in western Oregon and Washington have become increasingly interested in creating additional conifer cohorts in young, even-aged, second-growth Douglas-fir stands. The purpose of our research was to assess the establishment, survival, and growth of naturally-regenerated and underplanted conifers 10-13 years after overstory thinning and understory...
This study was conducted to investigate why root disease centers east of the
Cascade crest tend to be larger in diameter and more abundant than their counterparts to
the west, within subalpine forest stands of central Oregon. The trend in a 290 km² study
area appeared opposite of what was...
Root rot diseases are a major constraint to bean (Phaseolus vulgaris L.)
production around the world. Both snap beans and dry beans are affected. Root rot diseases can be caused by a variety of pathogens; however, Fusarium solani is a common causal agent. Fusarium root rot is a primary yield...
This publication discusses the environmental requirements of needle diseases, their potential impact on tree vigor, when disease levels signal a problem, and what you can do to minimize damage.
Published March 1936. 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
Equations for predicting individual-tree height growth per 5-year period are presented for Douglas-fir, white fir, grand fir, ponderosa pine, sugar pine, and incense-cedar growing in the mixed-conifer zone of southwest Oregon. The data used to develop the equations came from 3,648 trees sampled from 391 stands in the study area....