Exploratory Tree Survey (2016 - Eel River Critical Zone Observatory - Sagehorn - Central Belt Melange, Franciscan Complex, Northern California Coast Ranges, USA)

We surveyed more than 2,800 individual trees over an approximately 10 hectare area May 2-5, 2016 at the Eel River Critical Zone Observatory Sagehorn site in Mendocino County, California, USA. Trees species, size (height for juvenile and diameter for mature individuals), canopy position (for mature individuals), and location (meter-scale resolution GPS) were recorded. The survey area is a small portion of a 5,000 acre private cattle ranch that experienced a large fire in 1950 and some logging of Douglas fir in the first half of the twentieth century. The hilly landscape is part of the Central Belt Melange of the Franciscan Formation complex, and surveyed areas were underlain by sheared clay-rich melange matrix (dominant vegetation: annual herbaceous groundcover and Quercus garryana (Oregon White Oak)), as well as poorly sorted, immature sandstone blocks (greywacke; dominant vegetation: Arctostaphylos spp (Manzanita - not surveyed), Pseudotsuga menziesii (Douglas Fir) and Arbutus menziesii (Pacific Madrone)). Trees with diameters at breast height (1.4 m; DBH) greater than 5 cm (n = 313) were tagged for future surveys.