Douglas-fir typically has very well-defined annual rings, with a sharp definition between earlywood (light colored cells) and latewood (dark colored cells). For this reason, annual rings are very easy to count, making Douglas-fir a widely used species for dendrochronology and historical climate studies in western North America.
Please cite the article: Finch, K., E. Espinoza, F. A. Jones, and R. Cronn. 2017. Source identification of western Oregon Douglas-fir wood cores using mass spectrometry and random forest classification. Applications in Plant Sciences 5(5): 1600158. doi:10.3732/apps.1600158. Articles and materials published in Applications in Plant Sciences are licensed under a Creative Commons Attribution license (CC-BY-NC-SA).