The fine texture and friable nature of these soils suggests they will be highly susceptible to erosion if exposed. At present, the O horizon with its dense root mat provides a protective skin for the soft soil underneath. Providing additional protection are the permeable nature of the surface, which promotes infiltration rather than runoff, and the presence of the redwood canopy, which may diffuse the impact of raindrops. However, if the O horizon were removed, soil loss could be rapid and extensive. The O horizons are also important in themselves. They hold a significant percentage of the rootmass of the redwood trees and they cycle nutrients from the decomposition of the leaf litter back into the redwood roots. Every precaution should be taken to preserve the O horizons of these soils.

Redwood Forest Overstory.

No extraordinary conditions were observed with regard to tree vigor, mechanical damage, and tree pathogens. No areas showed signs of declining vigor. One area was noted, however, that was observed to be a poorer growing site than other areas of the Park. This area is located on a ridge along the Big Trees Trail and is identified as Area “I” on Figure 1. The redwood trees in this area are of much smaller diameters than in other areas of the Park, and they exhibit a shaggy bark condition that is more pronounced than seen on other trees of the Park (see Figure 2).