@mastersthesis {910, title = {Stand Replacing Fire History and Aspen Ecology in the Upper Rio Grande Basin}, volume = {Master of Science}, year = {2003}, pages = {94}, school = {University of Arizona}, address = {Tucson}, abstract = {

Dendroecological techniques were applied to reconstruct stand-replacing fire history in mixed conifer and spruce-fir forests in northern New Mexico and southern Colorado. Stand-replacing fire dates with annual accuracy and precision were determined using four lines of evidence for each of twelve sites within a 75,000 square kilometer area. The four lines of evidence were: (1) aspen inner-ring dates, (2) conifer death dates, (3) tree-ring width changes, or other morphological indicators of injury, and (4) fire scars. The annual precision of dating allowed the identification of significant synchrony of stand replacing fires among the 12 sites and regional surface fire events previously reconstructed from the large network of fire scar collections in the Southwest. Nearly all of these synchronous stand-replacing and surface fire years coincided with extreme droughts. This suggests that stand-replacing fire activity occurred primarily when drought conditions allowed fires to ignite and spread within these high elevation forests and/or for the spread of surface fires between lower and upper elevations. Fifty percent of reconstructed stand-replacing fires pre-dated large-scale Euro-American settlement in this region. This may suggest that land use practices (such as logging and mining) were not as important in promoting stand-replacing fires in these study sites, as compared with other areas in Colorado.

}, keywords = {aspen, basin, colorado, conifer, dendrochronology, dendroecology, Ecology, fire, fire history, new mexico, rio grande, spruce fir, stand replacing, tree ring}, author = {Margolis, Ellis Quinn} } @mastersthesis {558, title = {Tree-Ring Reconstruction of Western Spruce Budworm Outbreaks in the Rio Grande National Forest, Colorado}, volume = {Master of Science}, year = {1999}, pages = {97}, school = {University of Arizona}, address = {Tucson}, abstract = {

Tree-ring records were used to reconstruct the spatial and temporal patterns of western spruce budworm (Choristoneura occidentalis Freeman) outbreaks in the Rio Grande National Forest (RGNF) of southern Colorado. Reconstructions at 11 host stands showed a synchronous pattern of outbreaks with a peak in the number of trees recording outbreaks over the entire RGNF on average every 24 years. These synchronous periods of outbreaks coincided with periods of increased moisture as indicated by an independently reconstructed summer Palmer Drought Severity Index, while relatively few trees recorded outbreaks during dry periods. The reconstruction on the RGNF does not support the hypothesis that human land use has significantly altered outbreak patterns. Tree response to outbreaks in the RGNF was different from prior studies as reductions in the growth were typically detectable only when growth was compared to that of nonhost tree species.

}, keywords = {colorado, dendrochronology, department of agriculture, forest service, national forest, outbreak, palmer drought severity index, RGNF, rio grande, tree ring, western spruce budworm}, author = {Ryerson, Daniel E.} } @book {625, title = {Tree-Ring Dates from New Mexico C-D Northern Rio Grande Area}, year = {1971}, publisher = {University of Arizona}, organization = {University of Arizona}, address = {Tucson}, keywords = {Archaeology, date, dendrochronology, new mexico, rio grande, tree ring} }