Because of concern over widespread population declines, the distribution, stand conditions, and health of whitebark pine (Pinus albicaulis Englem.) were evaluated along the Pacific Crest National Scenic Trail on the Umpqua National Forest. Whitebark pine occurred on 76 percent of the survey transects. In general, whitebark pine was found in stands with lower overall densities and fewer late-seral species, particularly Shasta red fir (Abies magnifica var. shatensis A. Murr.) and mountain hemlock (Tsuga mertensiana [Bong.] Carr.). Whitebark pine stocking differed widely, from less than 1 up to 24 percent of the trees on transect plots. Most whitebark pines (87 percent) were less than 5 m tall. Of all whitebark pine encountered, 44 percent were alive and healthy, 46 percent were alive but infected by Cronartium ribicola (J.C. Fisch) (cause of white pine blister rust), and 10 percent were dead. Two-thirds of the mortality was due to white pine blister rust. Mountain pine beetle (Dendroctonus ponderosae Hopkins) alone accounted for 13 percent of the mortality, whereas evidence of mountain pine beetle was found with white pine blister rust on 18 percent of the dead whitebark pines. White pine blister rust affected trees in all but the largest size class; 70 percent of the whitebark pines greater than 1.5 m tall and less than 7.6 cm diameter at breast height (d.b.h.) were infected. Most (92 percent) of infected whitebark pines had bole cankers or cankers within 15 cm of the bole. No cones were observed on whitebark pines in any of the survey plots. Whitebark pine was common in centers of laminated root rot (caused by the fungus Phellinus weirii (Murrill.) R.L. Gilbertson) where substantial canopy openings were found. In these centers, whitebark pine contributed 73 percent of the large tree stocking. The results of this survey constitute a reference condition for whitebark pine that can be used to assess change in its status in this part of southwest Oregon. Measures to reduce the impacts of disease and bark beetles and to maintain whitebark pine populations are discussed.
A survey was done to provide forest managers in southwest Oregon with information about characteristics of Douglas-fir dwarf mistletoe (Arceuthobium douglasii) brooms used for nests by northern spotted owls (Strix occidentalis var. caurina). Data were collected on 35 nest brooms and nest trees. Site, stand, and mistletoe data were collected in variable-radius plots in a 20 ac area around 11 of the nest trees. On average, half the nest trees' crowns were occupied by brooms. Douglas-fir trees in variable radius plots immediately surrounding the nest trees were more heavily infected than trees in neighboring plots. The majority of owl nests were in Type 2 and 3 brooms. Few nests were in Type 1 brooms even though they were the most common broom type. The majority of nests were in brooms in the lower third of the tree crowns and on the lower to middle third of the slope. Survey results were used to make recommendations for managing infected trees and stands for current and replacement spotted owl nest habitat in the survey area. West. J. Appl. For. 18(2):115–117.
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