• Western Spruce Budworm Outbreak History in the Sacramento Mountains, New Mexico, U.S.A.

      Archambault, Sylvain; Swetnam, Thomas W.; Lynch, Ann M.; Centre d'etudes nordiques, Universite Laval, Ste-Foy (Quebec) Canada; Laboratory of Tree-Ring Research, University of Arizona; USDA Forest Service, Rocky Mountain Forest and Range Experiment Station (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 2013-10-04)
      Western spruce budworm (Choristoneura occidentalis Freeman) outbreak history was reconstructed for the Sacramento Mountains of south-central New Mexico, at the southern limit of the species distribution range. Six host tree-ring width chronologies (Douglas -fir and white fir) and three non -host control chronologies (ponderosa pine) were used for this reconstruction spanning from 1800 to 1990. Both the host and non-host species had similar climatic response so the non-host chronologies were confidently used as climatic controls. Up to eight defoliation events were documented within individual stands and at least seven major regional outbreaks were identified among the stands back to 1800. At least five major outbreaks occurred in the twentieth century: 1890s- 1900s, 1910s- 1920s, 1940s, 1960s, and 1980s. The 1960s and 1980s outbreaks were verified by Forest Service aerial and ground survey records. These recent outbreaks seemed to have been more synchronous among the different stands than outbreaks that occurred in the 19th century. There were similarities between this outbreak history and an outbreak history reconstructed for northern New Mexico, a distance of about 340 km to the north. The regional-scale pattern identified in these histories lends support to a hypothesis that past logging and fire suppression has changed western spruce budworm dynamics.
    • The Impact of Ozone on Sequoia Seedling Stem Structure: Implications for Seedling Survival

      Telewski, Frank W.; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 2013-10-04)
    • An Inventory of Bristlecone Pine in the Snake, Mount Moriah, Ward Mountain, and Schell Creek Divisions of the Humboldt National Forest

      Klemmedson, James O.; Beasley, R. Scott; Laboratory of Tree-Ring Research, University of Arizona; Department of Watershed Management, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 2013-10-01)
    • Final Progress Report First Year - National Park Service Contract Number 14-10-0232-903

      Weekly, Ward F.; Laboratory of Tree-Ring Research, University of Arizona (2012-09-24)
    • A multimillenial temperature reconstruction from far north-eastern Eurasia

      Hughes, Malcolm K.; Laboratory of Tree-Ring Research, University of Arizona (1996-07-31)
    • Fire History in Ponderosa Pine and Mixed-Conifer Forests of the Jemez Mountains, Northern New Mexico

      Touchan, Ramzi; Swetnam, Thomas W.; Laboratory of Tree-Ring Research, University of Arizona; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1995-03-20)
      We reconstructed fire history in ponderosa pine and mixed-conifer forests across the Jemez Mountains in northern New Mexico. We collected the fire-scarred samples from nine ponderosa pine areas and four mesic mixed-conifer areas. An additional collection was obtained from a bristlecone pine stand in the Sangre de Cristo Mountains. We also reconstructed December-June precipitation from ponderosa pine tree-ring indices that were developed from four different watersheds in northern New Mexico. Prior to 1900, ponderosa pine forests were characterized by high frequency, low intensity surface fire regimes. The mixed-conifer stands sustained somewhat less frequent surface fires, along with patchy crown fires. In both ponderosa pine and mixed-conifer forests precipitation was significantly reduced in the winter-spring seasons preceding fire events. In addition, winter-spring precipitation during the third year preceding major fire years in the ponderosa pine forest was significantly increased. This study provides baseline knowledge concerning the ecological role of fire in ponderosa pine and mixed-conifer forests. This information is vital to support ongoing ecosystem management efforts in the Jemez Mountains.
    • Climate in North-Central China from tree-ring variables

      Hughes, Malcolm K.; Leavitt, Steven W.; Laboratory of Tree-Ring Research, University of Arizona (1993)
    • Dendroecological Research on Mt. Graham: Development of Tree-Ring Chronologies for the Pinaleño Mountains

      Grissino-Mayer, Henri D.; Swetnam, Thomas W.; Laboratory of Tree-Ring Research, University of Arizona (1992-03-30)
    • Ethylene Production By Different Age Class Ponderosa and Jeffery Pine Needles as Related to Ozone Exposure and Visible Injury

      Telewski, Frank W.; Laboratory of Tree-Ring Research, University of Arizona (Springer-Verlag, 1992)
      Ethylene production by different needle age classes was characterized using a mercuric perchlorate traps in natural populations of two ponderosa pine varieties (Pinus ponderosa var. arizonica [Engelm] Shaw and var. ponderosa Dougl. ex Laws.) and Jeffery pine (Pinus leffrevi Grev. and Balf.). All ozone -exposed populations contained individuals which were symptomatic and asymptomatic with respect to visible ozone injury. Ethylene production of different needle age classes was also characterized in Pinus ponderosa var. ponderosa seedlings grown in open top ozone fumigation chambers. Older age class needles produce more ethylene than younger age class needles. Needles of both P. ponderosa var. ponderosa and P. jeffreyi exhibiting ozone injury in the field produced significantly (p >0.05) higher levels of ethylene than asymptomatic conspecifics. Seedlings exposed to highest treatment level of ozone in the fumigation study produced the highest levels of ethylene followed by fumigation with medium and low ozone concentrations and carbon filtered air. These data indicate that measurement of ethylene in conifer needles as a measure of stress needs to be calibrated for needle age class. It also suggests that the sensitivity of a tree to ozone injury may be regulated by the inherent ability of the individual to produce ethylene.
    • Southwest Archaeological Tree-Ring Dating

      Dean, Jeffrey S.; Robinson, William J.; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1991-01-31)
    • Tree-Ring Evidence for Long-Term Climatic Change: Yosemite National Park

      Graumlich, Lisa J.; Laboratory of Tree-Ring Research, University of Arizona (1990-12-15)
      Tree -ring data were collected from two sites within Yosemite National Park: a western juniper stand near Juniper Ridge and a lodgepole pine stand near Gaylor Lakes. Analyses of standardized and prewhitened tree-ring indices from the two sites indicate that at both sites winter (January through March) precipitation is the factor most limiting to tree growth. Using regression analysis a model predicting winter precipitation as a function of tree growth was developed and tested. The model explains 32% of the variance of the precipitation data. While the model is statistically significant, the explanatory (and hence predictive) power of the model could be enhanced by further core collection. When the model is applied to the early portion of the tree -ring record, a reconstruction of precipitation extending back to AD 1620 is obtained. Extended droughts are common in the record and include the following periods: 1650 -1648, 1700 -1720, 1749 -1758, 1807 -1824, 1842- 1851, 1885 -1893, and 1911 -1934. Further funding is being sought to expand the tree-ring data base allowing for more accurate climatic reconstruction and a longer temporal extent of the reconstruction.
    • Analysis of Growth Trends and Variation in Conifers from Arizona and New Mexico: Youthful Trees, Competition, and Densitometric Chronologies

      Graybill, Donald A.; Swetnam, Thomas W.; Telewski, Frank W.; Park, Wonkyu; Laboratory of Tree-Ring Research, University of Arizona; Buffalo and Erie County Botanical Garden; Department of Forest Products, Chungbuk National University (1990-10-26)
    • Dendrometer, Dendrograph and Phytogram Characteristics of Douglas Fir and Southwestern White Pine in the Rincon Mountains

      Gensler, W.; Agricultural Electronics Corporation, Tucson, Arizona (Agricultural Electronics Corporation (Tucson, AZ), 1990-07-01)
    • Fire Scar Dates from Walnut Canyon National Monument, Arizona

      Swetnam, Thomas W.; Wright, William E.; Caprio, Anthony C.; Brown, Peter M.; Baisan, Christopher H.; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1990-01-03)
      Eighteen samples of fire-scarred ponderosa pine (Pinus ponderosa Laws.) from Walnut Canyon National Monument (Fig. 1) were delivered to the Laboratory of Tree-Ring Research in September 1989. These partial cross section samples were prepared and dendrochronologically dated. This report contains a brief description of the methods used in this project, and a detailed listing of the dating results. Some preliminary observations of the character of fire history are offered.
    • Fire and Flood in a Canyon Woodland: The Effects of Floods and Debris Flows on the Past Fire Regime of Rhyolite Canyon, Chiricahua National Monument: Final Report

      Swetnam, Thomas; Baisan, Christopher; Caprio, Tony; McCord, Alex; Brown, Peter; Laboratory of Tree-Ring Research, University of Arizona (1990)
      Prior research in the Rhyolite Canyon area of Chiricahua National Monument (Swetnam et. al. 1989) revealed an anomalous 50 year fire-free interval between 1901 and 1851. Disruption of fire spread resulting from flooding and mass soil movement (debris flows) were postulated as potential causes of this long interval. The present study gathered additional evidence of fire and floods in the canyon system. Sampling of flood-scarred trees along stream channels successfully identified several flood events in Rhyolite canyon. Pulses of pine regeneration on debris flow deposits were associated with one of these events. However, no definitive linkage of flood events with changes in fire regime was established. Analysis of new fire scar samples combined with previous results indicated that the area affected by the change in fire regime includes the uplands between Jesse James Canyon and Rhyolite drainage. Source areas for fires prior to 1900 were not identified within the study area indicating that ignitions outside the present monument boundaries may have been important in the past. Evidence from the maximum ages of overstory conifers within Rhyolite Canyon suggests the occurrence of a major disturbance within this drainage prior to 1600.
    • Fire History of Rhyolite Canyon, Chiricahua National Monument

      Swetnam, Thomas W.; Baisan, Christopher H.; Brown, Peter M.; Caprio, Anthony C.; Laboratory of Tree-Ring Research, University of Arizona (Cooperative National Park Resources Studies Unit, School of Renewable Natural Resources, University of Arizona, 1989-08)
    • Drought History and Reconstructions from Tree Rings

      Stockton, Charles W.; Meko, David M.; Boggess, William R.; Laboratory of Tree-Ring Research, University of Arizona; Laboratory of Tree-Ring Research, University of Arizona; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1989-07)
    • Giant Sequoia Fire History: A Feasibility Study

      Swetnam, Thomas W.; Baisan, Christopher H.; Brown, Peter M.; Caprio, Anthony C.; Harlan, Thomas P.; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1988-06-30)
    • Analysis of Growth Trends and Variation in Conifers from Central Arizona: I. Network Chronology Development and Analysis

      Graybill, Donald A.; Rose, Martin R.; Laboratory of Tree-Ring Research, University of Arizona (1988)
    • Climatic Regimes of the Pacific Sector and Adjacent Continents Since 1600: A Synoptic Description and Comparison of Independent Climate Proxy Records

      Fritts, Harold C.; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1987-06)