The Importance of Large-Diameter Trees to Forest Structural Heterogeneity
Four images from different parts of the WFDP illustrate defining characteristics of the ecosystem. The forest is composed of an overstory of large-diameter trees with abundant but heterogeneous woody low shrub and herbaceous layers. Vegetation communities include Tsuga heterophylla/Mahonia nervosa (upper left image, August 19, 2012), and Tsuga heterophylla/Mahonia nervosa/Gaultheria shallon (upper right image, May 8, 2010). Regeneration by the shade-tolerant Tsuga heterophylla can be locally dense (lower right image, August 31, 2012). The most abundant species by stems, Acer circinatum, creates a seasonal sub-canopy layer (lower left image, May 8, 2010). All photos by J. A. Lutz.