Zobel, D. B.; McKee, W. A.; Hawk, G. M.; Dyrness, C. T. 1974. Correlation of forest communities with environment and phenology on the H.J. Andrews Experimental Forest, Oregon. In: Waring, R. H.; Edmonds, R. L., eds. Integrated research in the coniferous forest biome. Bulletin 5. Seattle, WA: Coniferous Forest Biome: 48-56.
Air and soil temperature, leaf nutrient content, late summer plant mois-ture stress, and phenology were measured on 14 of the 23 forest communi-
ties recognized in the study area. The three vegetation zones identified
differ considerably in a temperature index. Comparisons of an existingvegetation ordination with ordinations made using the results of thisstudy showed that the x axis of the vegetation ordination represents amoisture axis. Although both temperature and nutrition correlate tosome extent with the y axis of the ordination, it is not simply a re-sponse to any one or two factors studied. Yearday of selected pheno-logical stages, is well correlated with the temperature index used, butnot with ordination axes.
The maximum predawn moisture stress and the calculated temperature indexeffectively separate the previously classified communities in the studyarea. The range of the environmental indexes measured in this area is
very similar to that in the eastern Siskiyou Mountain forests.