@mastersthesis {842, title = {Fire History and Fire Climate Relationships in Upper Elevation Forests of the Southwestern United States}, volume = {Ph.D}, year = {2007}, note = {

Please contact the Laboratory of Tree Ring Research for a copy of this dissertation. The file is too large to be uploaded at this time.

}, pages = {182}, school = {University of Arizona}, type = {Dissertation}, address = {Tucson}, abstract = {

Fire history and fire-climate relationships of upper elevation forests of the southwestern United States are imperative for informing management decisions in the face of increased crown fire occurrence and climate change. I used dendroecological techniques to reconstruct fires and stand-replacing fire patch size in Madrean Sky Islands and Mogollon Plateau. Reconstructed patch size (1685-1904) was compared with contemporary patch size (1996-2004). Reconstructed fires at three sites had stand-replacing patches totaling \> 500 ha. No historical stand-replacing fire patches were evident in the mixed conifer/aspen forests of the Sky Islands. Maximum stand-replacing fire patch size of modern fires (1129 ha) was greater than that reconstructed from aspen (286 ha) and spruce-fir (521 ha). Updated spruce-fir patches may be evidence of larger (\>2000ha) stand-replacing fire patches.

To provide climatological context for fire history I used correlation and regionalization analyses to document spatial and temporal variability in climate regions, and El-Nino Southern Oscillation (ENSO), the Pacific Decadal Oscillation (PDO) and the Atlantic Multi-decadal Oscillation (AMO) teleconnections using 273 tree-ring chronologies (1732-1979). Four regions were determined by common variability in annual ring width. The component time score series replicate spatial variability in 20th century droughts (e.g., 1950\’s) and pluvials (e.g., 1910\’s). Two regions were significantly correlated with instrumental SOI and AMO, and three with PDO. Sub-regions within the southwestern U.S. varied geographically between the instrumental (1900-1979) and the pre-instrumental periods (1732-1899). Mapped correlations between ENSO, PDO and AMO, and tree-ring indices illustrate detailed sub-regional variability in teleconnections.

I analyzed climate teleconnections, and fire-climate relationships of historical upper elevation fires from 16 sites in 8 mountain ranges. I tested for links between Palmer Drought Severity Index and tree-ring reconstructed ENSO, PDO and AMO phases (1905-1978 and 1700-1904). Upper elevation fires (115 fires, 84 fire years, 1623-1904) were compared with climate indices. ENSO, PDO, and AMO affected regional PDSI, but AMO and PDO teleconnections changed between periods. Fire occurrence was significantly related to inter-annual variability in PDSI, precipitation, ENSO, and phase combinations of ENSO and PDO, but not AMO (1700-1904). Reduced upper elevation fire (1785-1840) was coincident with a cool AMO phase.

}, keywords = {AMO, climate, dendrochronology, dendroclimatology, ENSO, environment, fire, fire history, forest, madrean sky islands, mogollon plateau, mountain, PDO, southwest, teleconnection, tree ring, upper elevation, Watershed Management}, url = {http://ezproxy.library.arizona.edu/login?url=http://proquest.umi.com/pqdweb?did=1375523671\&sid=1\&Fmt=2\&clientId=43922\&RQT=309\&VName=PQD.}, author = {Margolis, Ellis Quinn} } @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.} } @mastersthesis {516, title = {Fire History in Riparian Canyon Pine-Oak Forests and the Intervening Desert Grasslands of the Southwest Borderlands: A Dendroecological, Historical, and Cultural Inquiry}, volume = {MS}, year = {1998}, school = {University of Arizona}, address = {Tucson}, abstract = {

Dendroecological, documentary, and ethnoecological evidence were combined to provide an integrated understanding of past natural and cultural fires in the Southwest Borderlands. Fire frequency for the desert grasslands was inferred from synchronous intercanyon fire events. Mean fire intervals range between 4-8 years in canyon pine-oak forests, 4-9 years in the intervening desert grasslands, and 5-9 years in the mixed-conifer forests. Riparian canyon pine-oak forests were important corridors for fire spread between the desert grasslands and higher-elevation forests. The decline of post-settlement (\>1870s) fires typical of most forests in U.S., is not evident south of the border in Mexico.

Documentary evidence reveals the Apache had detailed knowledge of fire, that burning practices were controlled and limited, and ecosystem enhancement through intentional burning was not suggested. However, the common exception was burning practiced during wartime periods, principally by the Apache but also by the Spanish, Mexicans, and later Americans. Fire reconstructions indicate that wartime-period fires were significantly more frequent than peacetime periods at several canyon-rancher{\'I}a sites.

}, keywords = {apache, borderland, cultural, dendrochronology, dendroecological, desert grassland, ethnoecological, fire, fire history, historical, Mexico, oak, peacetime, pine, post settlement, riparian, southwest, spanish, wartime, Watershed Management}, author = {Kaib, J. Mark} } @mastersthesis {439, title = {Fire Histories of Upper Elevation Forests in the Gila Wilderness, New Mexico via Fire Scar and Stand Age Structure Analyses}, volume = {Master of Science}, year = {1997}, pages = {120}, school = {University of Arizona}, address = {Tucson}, abstract = {

Fire-scar analysis to identify fire events and stand age structure analysis to identify fire effects on survivorship of trees were used to reconstruct surface and crown fire regimes in upper elevation forests of the Gila Wilderness, NM. Fire regimes varied across forest type, but not necessarily across elevation. Prior to the twentieth century, (from 1706 to 1904), the mean interval for large fires was 8 years. During the twentieth century, (from 1904 to 1995), the mean fire return interval for large fires was 46 years. The virtual end of historically frequent fire regimes due to livestock grazing and fire suppression since the turn of the century has affected successional pathways of forest types across elevations, favoring later successional forest species and structures.

}, keywords = {dendrochronology, fire, fire regime, fire scar, gila wilderness, new mexico, stand age, suppression, tree ring, upper elevation}, author = {Abolt,Rena Ann Peck} } @mastersthesis {538, title = {Reconstruction and Interpretation of Historical Patterns of Fire Occurrence in the Organ Mountains, New Mexico}, volume = {Master of Science}, year = {1996}, pages = {144}, school = {University of Arizona}, address = {Tucson}, abstract = {

The purpose of this research was to reconstruct and interpret the history of fire in the Organ Mountains, New Mexico. I used dendrochronological techniques to date fire scars on 90 trees comprising ten sites within the Fillmore Canyon watershed. Two fire regimes were identified during the pre-settlement period. Fire Regime I, 1650-1805, was characterized by a high fire frequency (ca. once every two years) and a predominance of patchy fires. Fire Regime II, 1805-1874, was characterized by a lower fire frequency (ca. once every 3.5 years) and a predominance of widespread fires. During the post-settlement period fire was virtually non-existent. I hypothesize that Apache use-of-fire influenced patterns during the pre-settlement period, while Euro-American land use activities influenced patterns during the post-settlement period. Fire-precipitation associations suggest that low fuel moisture levels were a pre-condition for widespread fires.

}, keywords = {dendrochronology, fillmore canyon, fire, Geography, historical, new mexico, organ mountains, reconstruction}, author = {Morino, Kiyomi Ann} } @mastersthesis {550, title = {A Dendroecological Assessment of Whitebark Pine in the Sawtooth Salmon River Region Idaho}, volume = {Master of Science}, year = {1995}, pages = {56}, school = {University of Arizona}, address = {Tucson}, abstract = {

Whitebark pine (Pinus albicaulis Engelm.) tree-ring chronologies of 700 to greater than 1,000 years in length were developed for four sites in the Sawtooth-Salmon River region, central Idaho. These ring-width chronologies are used to (1) assess the dendrochronological characteristics of this species, (2) detect annual mortality dates of whitebark pine attributed to a widespread mountain pine beetle (Dendroctonus ponderosae Hopk.) epidemic during the 1909 to 1940 period, and (3) establish the response of whitebark pine tree ring-width growth to climate variables. Crossdating of whitebark pine tree-ring width patterns was verified. Ring-width indices had low mean sensitivity (0.123-0.174) typical of high elevation conifers in western North America, and variable first order autocorrelation (0.206-0.551). Mortality of dominant whitebark pine caused by mountain pine beetle had a maxima at 1930 on all four sites. Response functions and correlation analyses with state divisional weather records indicate that above average radial growth is positively correlated with winter and spring precipitation and inversely correlated with April temperature. These correlations appear to be a response to seasonal snowpack. Whitebark pine is a promising species for dendroclimatic studies.

}, keywords = {dendrochronology, dendroclimatology, dendroctonus ponderosae, dendroecology, idaho, pine beetle, pinus albicaulis, sawtooth salmon river, tree ring, whitebark pine}, author = {Perkins, Dana Lee} } @mastersthesis {573, title = {Fire History of the Gila Wilderness, New Mexico}, volume = {Master of Science}, year = {1983}, pages = {156}, school = {University of Arizona}, address = {Tucson}, abstract = {

A data base of fire occurrence was established for the Gila Wilderness by analyzing fire scars and compiling fire records. Cross sections of 44 fire scarred ponderosa pine trees (Pinus ponderosa Laws.) were collected from three study areas. Crossdating of more than 800 individual fire scars revealed that extensive surface fires were a common occurrence prior to 1900. Mean fire intervals for a 250-year period prior to 1900 were approximately four to eight years and fire intervals ranged from one to 26 years. Intensive grazing and fire suppression efforts after 1900 resulted in a sudden decrease in number of fires recorded by the sample trees.

A 72-year record (1909-1980) of fire occurrence in the Gila National Forest was compiled from Forest Service records. The fire records and fire scar evidence suggest a need for continued emphasis on fuels reduction and greater flexibility in the Prescribed Natural Fire program.

}, keywords = {crossdate, dendrochronology, fire, fire history, fire scar, gila national forest, gila wilderness, new mexico, pinus ponderosa, ponderosa pine, tree ring}, author = {Swetnam, T.} }