The benomyl fungicide, rersan, applied at 7 and 14 pounds active ingredient per acre, on April 26 and July 25, 1973, was ineffective in reducing mortality in 2-0 Engelmann spruce seedlings derived from two different seed sources growing in three different nursery sections at the USFS Coeur d'Alene Nursery. Percent...
Tests were conducted at the USDA Forest Service Nursery, Coeur d'Alene, Idaho to evaluate effectiveness of spring fumigation with dazomet to improve survival and performance of Douglas-fir and western white pine transplants. Spring fumigation greatly reduced populations of potentially pathogenic Fusarium and Pythium spp. Disease levels of container (plug+1) and...
Published September 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
Laminated root rot of Douglas-fir (Pseudotsuga menziesii (Mirb.)
Franco) caused by the fungus Phellinus weirii (Murr.)Gilbertson was
studied in two successive stands in the Oregon Coast Range. Damage
due to the disease in a 60-year-old second-growth stand was compared
with incidence in the preceding 300-year-old stand on the same site....
Two thousand and thirty-nine trees on 213 plots are being monitored yearly for
root disease infection and mortality. Three compartments on the Fernan Ranger
District of the Idaho Panhandle National Forests are the site of the project.
Relationships between factors such as species, aspect, slope, elevation,
habitat type, stand appearance...
Root diseases were evaluated on the Reuben's Reserve, Nez Perce Indian Reservation, Idaho. Nineteen trees adjacent to two suspected root disease centers were pushed with a D-6 tractor to expose their root systems. Extent of root necrosis and decay was determined and related to level of crown thinning, chlorosis, and...
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...
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...
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...
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
The coniferous forests of the Pacific Northwest are
affected by a variety of endemic fungal root pathogens. Forest
disease surveys have noted the presence of two or more of
these root pathogens infecting the same stump or root, and it
has been suggested that these fungi may be interacting
synergistically....
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,...
Since around 1923 Port-Orford-cedar (Chamaecyparis lawsoniana (A. Murray) Parl.) has been affected by Phytophthora root disease caused by the virulent introduced pathogen Phytophthora lateralis. A systematic resistance testing and breeding program located at the USDA Forest Service Dorena Genetic Resource Center in Cottage Grove, Oregon was initiated in 1997 with...
Two methods attempting to stop marginal spread of a root disease center in Douglas-fir were evaluated within the Flathead Indian Reservation, Montana. The first method was to cut all living trees within a 1-chain strip outside the edge of the infestation. The second method was to uproot all trees for...
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...
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...