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 was achieved for the crop (5.5 percent of the crop was lost to diseases or other mortality factors). Dead or diseased seedlings accounted for only 0.7 percent of the total losses, whereas empty cells accounted for the remaining 4.8 percent. Major disease organisms included Sirococcus strobilinus, Fusarium oxysporum, F. avenaceum, F. solani, F. tricinctum, Cylindrocarpon tenue, Phoma herbarum, P. fimeti, and Botrytis cinerep. Sirococcus caused disease in 18 of the 19 seedlots and was usually encountered about 11 weeks after sowing. Fusarium diseases occurred with greatest frequency shortly after germinate emergence.
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