Benomyl and chlorothalonil were tested on 2-0 bareroot ponderosa pine seedlings as a means to reduce impact of Diplodia tip blight at the Fantasy Farms Nursery, Peck, Idaho. Infection levels were not adequate to assess effectiveness of the fungicides. However, techniques were developed which can be used to assess efficacy...
Treating styroblock containers in hot water (68°C) with a very dilute bleach and detergent solution effectively reduced populations of Fusarium and Cylindrocarpon spp., two potential root pathogens of containerized conifer seedlings. However, the treatment did not significantly reduce levels of Phoma (another potential pathogen) nor saprophytic Penicillium and Alternaria spp....
A total of 45 nondiseased containerized ponderosa pine seedlings from 10 seedlots were sampled at three different times during the growing season for root infection by Fusarium and Trichoderma at the USDA Forest Service Nursery in Coeur d'Alene, Idaho. More than 90 percent of the seedlings had roots infected with...
Fungi associated with cankers of Russian-olive seedlings at the Montana State Nursery, Missoula, were investigated. Phomopsis elaeagni was most often isolated from and fruiting on cankers. Other associated fungi were Phoma herbarum, P. eupyrena, P. chrysanthemicola, P. exigua, Alternaria alternate, Epicoccum nigrum, and Fusarium moniliforme. Because of its common occurrence...
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...
An evaluation was conducted at the USDA Forest Service Nursery, Coeur d'Alene, Idaho, to quantify the occurrence of diseases in the spring 1984 crop of containerized Engelmann spruce seedlings. The crop included 19 separate seedlots from seven National Forests in the Northern Region. An overall production rate of 94.5 percent...
Mortality of containerized western white pine seedlings outplanted on the Bonners Ferry Ranger District, Idaho Panhandle National Forests, was probably due to extensive root infection by Fusarium oxysporum. Diseased seedlings had chlorotic foliage, needle tip dieback, and severe twisting of the needles that indicated wilting. Most root tips of diseased...
Whitebark pine is an important reforestation species in the northern Rocky Mountains for enhancement of wildlife habitat. Production of container-grown whitebark pine seedlings at the USDA Forest Service Nursery in Coeur d'Alene, Idaho has been increasing the past several years. Diseases continue to be an important limiting factor in seedling...
Soil in Field 2 at the USDA Forest Service Nursery, Coeur d'Alene, Idaho was assayed six times over a 2-year fallow period for potentially pathogenic Fusarium and Pythium spp. following incorporation of a corn cover/green manure crop. Populations of potentially disease-antagonistic Trichoderma spp. were also assayed. Soil populations of Fusarium...