Oregon State University

Can’t find an event? We’re busy migrating to a new event calendar. Try looking at the new calendar



Event Details

Thesis Defense: Byrne Miyamoto

Assessing the Potential Utilization of Western Juniper as a Building Material

Monday, May 8, 2017 10:00 AM - 11:00 AM

Western juniper (Juniperus occidentalis) is a conifer that is native to Oregon, California, Washington, Nevada, and Idaho. Juniper is known to have highly decay resistant heartwood and is a popular choice for finished furniture. With recent forest management practices over the past 100 years have resulted in an immense population increase in western juniper stands, transforming the grasslands/sagebrush into juniper forests. Landowners have been encouraged to cutback western juniper to restore grassland habitat, but there is no major market associated with juniper. This study assessed the strength and durability properties of western juniper in order to develop design values in collaboration with the West Coast Lumber Inspection Bureau (WCLIB). The data will be presented to American Lumber Standard Committee (ALSC) for inclusion in the National Design Specification. Design values assigned to western juniper will allow contractors to use this species in structural and non-structural applications, especially for State funded projects.


Samples were harvested from three locations in eastern Oregon, one location in northeast California, and one location in southwest Idaho. Tests were performed according to procedures described in ASTM Standard D143 small-clear specimens for compression, bending, and shear. Average strength values were calculated and compared to similar wood species. Most properties were similar to those of other species, but modulus of elasticity was significantly lower. The differences between species might be attributed to cell wall structure and distribution of lignin in the cells. Design values for western juniper were calculated using the strength values following the ASTM Standard D245 procedure for establishing structural grades and related allowable properties for visually graded lumber.


Durability of western juniper was assessed using laboratory decay tests, marine tests, and ground contact exposure. The long term marine durability and ground contact tests are still on going. The laboratory decay test indicated that western juniper heartwood was highly resistant to attack by brown and white rot fungi. 



Byrne Miyamoto grew up in Ventura, California. He enjoyed the outdoors when he was young and wanted to go into forestry. He moved to Oregon to attend Oregon State University in the College of Forestry. He started his college career in forest management, but soon became inserted in forest products after obtaining a student researcher position for the wood science department. He graduated in 2014 with a Renewable Materials Degree, with a minor in Forest Management.  He is now a graduate student in the wood science and engineering department at Oregon State University working with Arijit Sinha on a project to assess the strength of western juniper to be able to assign design values for the species.



Valley Library (campus map)
Willamette West
Jessica King
Jessica.King at oregonstate.edu
Wood Science & Engineering
This event appears on the following calendars: