Southeastern Section - 64th Annual Meeting (19–20 March 2015)

Paper No. 34
Presentation Time: 8:00 AM-12:00 PM

GEOMORPHIC AND CLIMATIC IMPLICATIONS FROM SUB-ALPINE TREE CORES IN DEVIL'S CANYON, IDAHO


REAGAN, Audra N.1, JOHNSON, Bradley G.2, STACHOWIAK, Lauren A.3 and GRISSINO-MAYER, Henri3, (1)Environmental Studies, Davidson College, Davidson, NC 28035, (2)Environmental Studies, Davidson College, Box 7056, Davidson, NC 28035-7056, (3)Geography, University of Tennessee, Laboratory of Tree-Ring Science, 1000 Philip Fulmer Way, Knoxville, TN 37996, aureagan@davidson.edu

Devil’s Canyon, located near Leadore, Idaho and situated at approximately 2760 m in elevation, is the home to a forest of whitebark pine (Pinus albicaulis, Engelm.), subalpine fir (Abies lasiocarpa, Nutt.), and engelmann spruce (Picea engelmannii, Engelm.). Steep, rocky terrain paired with harsh environmental conditions in the area has resulted in relatively climatic, or sensitive trees, some that are more than 600 years old. We extracted 36 cores from a mixed stand of whitebark pine and subalpine fir immediately adjacent to the toe of the Devil’s Canyon rock glacier. Additionally, we collected five cores from dead trees killed by the advancing rock glacier. The objective of our study was to determine timing and rate of rock glacier advance using the dead trees along the toe of the rock glacier. Further, we aimed to evaluate whether or not tree samples collected from Devil’s Canyon are suitable to reconstruct climate in the area. A chronology of 17 tree cores has been developed for whitebark pine at two sites in the area that spans 631 years, from 1381 to 2013. The dead trees were cross-dated with the living chronology to determine the timing of advance and multiple trees across a transect were examined for rock glacier movement rate. Furthermore, the master chronology indicates that trees in the area are moderately sensitive to climate and exhibit a number of drought years identified in previous studies. These drought years include 1630, the 1850s, the 1930s, 2004, and 2005. The age of the trees in the area indicate their usefulness in studying both geomorphic processes and paleoclimate. Further work is required to determine if the cores examined contain data on longer-term climate trends in the region.