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Prof. Joy Mast presents research at national meeting in Washington D.C.

  • Joy Mast
April 11, 2019

Geospatial science professor Joy Mast presented her research at the national meeting of the American Association of Geographers in Washington D.C. Her research focuses on differing effects of mortality agent on standing dead trees (snags) persistence in southwestern ponderosa pine forests.

She conducted a longevity analysis to predict the lifespans of snags from large high-intensity fires and bark beetle outbreak and determine characteristics of snags that remaining standing. After repeat field sampling >2500 snags 1-13 years post-mortality, she determined a 7-year time period for a snag to remain standing. Mortality agent was the strongest predictor of how long a snag stood, with the hazard of falling for beetle-killed snags 2.5 greater than for fire-killed snags. Beetle-killed snags with intact tops, higher degree lean, and smaller diameter were most likely to fall. 

Prof. Mast’s long-term study provides a useful model to forest managers seeking to select longer-standing snags for wildlife immediately following a high-intensity fire or beetle outbreak. When combined with increased drought-related tree stress due to climate change, snag demography reported in her research indicates future conditions in a broader geographic region of western United States.