Durability Assessment of Western Juniper from Five Different Growing Regions


  • Byrne T Miyamoto
  • Matthew J Konkler
  • Scott Leavengood
  • Jeffrey J Morrell
  • Arijit Sinha Oregon State University


Western juniper, heartwood, decay resistance, G. trabeum, T. versicolor, extractives


The relationship between extractives content and resistance to fungal attack was examined in heartwood samples of western juniper (Juniperus occidentalis) collected from across the growing range.  Mass losses of juniper samples exposed to Trametes versicolor were generally low and indicated that this species would be classified as highly durable, while mass losses for samples exposed to Gloeophyllum trabeum were higher and suggested that juniper heartwood was slightly less resistant to this fungus.  Extractives levels were generally poorly correlated with decay resistance, but there were substantial differences in extractives content between samples from different geographic areas.   The results suggest the need for further evaluation of a wider range of samples to better determine the relationship between extractives and decay resistance.

Author Biography

Arijit Sinha, Oregon State University

Associate Professor


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Research Contributions