Parasitoid species attacking sparse, endemic populations of Choristoneura occidentalis Freeman and C. retiniana (Walsingham) are reported from 2 years of host collections at seven sites across southern Oregon. Results are compared with rearings from epidemic populations either from the same region or the same plot. Collections were designed to allow quantitative estimation of host density. Most of the parasitoid species present during epidemics across North America were recovered from the endemic and epidemic populations studied. The major difference is that at endemic host densities Glypta fumiferanae (Viereck) (Ichneumonidae) is rare to absent, whereas ichneumonids of the tribe Campoplegini, especially Tranosema (= Diadegma) interruptum (Ashmead), are common. This is the reverse of the situation at epidemic densities and consistent with results reported from eastern North America. It is suggested that the observed shift in the parasite complex with budworm density has the potential for predicting population trends.
Deciduosis of the appendix is a rare cause of acute appendicitis in pregnancy. Ectopic decidual cells localized in the submesothelial stroma may represent a physiologic reaction of the pluripotent stromal cells to progestational hormonal stimulation. Less frequently, deciduosis is based on a preexisting extragenital endometriosis, visible in a localization other than strictly submesothelial, in residuals of cyclic proliferation and bleeding, and in endometrial glandular formations embedded in the decidual cells.
Data collected from Douglas-fir (Pseudotsuga menziesii) stands infested by the Douglas-fir beetle (Dendroctonus pseudotsugae) in Wyoming, Montana, Idaho, and Utah, were used to develop models to estimate amount of mortality in terms of basal area killed. Models were built using stepwise linear regression and regression tree approaches. Linear regression models using initial Douglas-fir basal area were built for all study sites but produce low precision estimates. Regression tree models using initial Douglas-fir basal area or stand density index or both were also built for all sites. Regression tree models provide a more realistic approach to estimate potential mortality by creating more homogenous mortality classes with reduced variance. The models developed provide land managers with a basis for determining the potential mortality should a Douglas-fir beetle outbreak develop. West. J. Appl. For. 14(3):121-127.
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