Introduction: Ecological investigation of an area ordinarily follows a certain course. First explorations attempt to discover the nature of the flora, and ecological information is incidental to the habitat notes of collected species. Later, general qualitative observations appear regarding he vegetation of particular habitats. Only after this is a quantitative study using quadrats or other sampling techniques begun, and this quantitative work lays the foundation for future autecological, ecosystem and productivity work. Traditionally the above course is followed first by workers in vascular plant ecology, and studies of cryptograms are seldom as far advanced as that of the spermatophytes.
The vascular vegetation of the southern Appalachians is well known, due to the important works of Cain (1935), Whittaker (1956), and others. Studies in the spruce-fir zone of the Great Smoky Mountains National Park are exceptionally complete (Cain, 1935; Crandall, 1958; Schofield, 1960). The knowledge of the bryoecology of the boreal coniferous zone is not, however, so adequate. Sharp (1939) has provided an excellent bryophyte flora of eastern Tennessee, and Cain and Sharp (1938) did important exploratory work in which many of the bryophyte communities recognized in this study were described.
The present report is based upon researches made on the bryophyte communities of the major substrates in the spruce-fir zone of the southern Appalachians. It attempts to deal now only with the vegetational compostion of each community but also with a description of the frequency of that bryophyte community in the plant association as a whole. The studies were made from 1958 to 1963 during all months of the year, but primarily in summer and fall. Most of the work was done in the Great Smoky Mountains National Park, but excursion were also made to most of the other mountainous areas in North Carolina and Tennessee which have a forest dominated by boreal conifers. The spruce-fir forest of the Adirondacks of New York was also visited for comparative studies. In the Smokies every area of spruce and fir accessible by trail was seen at least once. The region on Forney Ridge between Mt. Kephart and Siler Bald, and the Mt. LeConte area were most intensively studied because of their easy accessibility. Figure 1, adapted from Crandall (1957), illustrates the location of spruce and fir in the Great Smoky Mountains National Park and maps the location of some of the places mentioned in this paper.
The data obtained in this study have laid a foundation for more intensive examination of particular communities, using objective methods of classifying and quantifying vegetation instead of this very subjective ones here used
