Figure 7. Structure and composition of the Yosemite Forest Dynamics Plot (YFDP).

Four images from different parts of the YFDP illustrate defining characteristics of the ecosystem. Most precipitation falls in the winter as snow yielding a spring snowpack of approximately 1 m (upper left image, April 11, 2011). The forest is composed of an overstory of large-diameter trees with abundant but heterogeneous shrub and herbaceous layers (upper right image, June 22, 2009). Shrubs can be locally dense enough to reduce tree recruitment (lower left image, June 22, 2009). Although most trees and shrubs are evergreen, the presence of the deciduous species Cornus nuttallii and Quercus kelloggii results in seasonal openings in the canopy (lower right image, November 11, 2010). All photos by J. A. Lutz.