Development of a Mixed-Shrub-Planted Ponderosa Pine Community on a Poor Site after Site Preparation and Release

摘要

Ideally, each land type or segment of commercial forest land in California will provide valuable amenities and commodities, and serve as a needed species/structure/age component of an ecosystem. But for the land manager to obtain the desired amenities and commodities, knowledge is needed on what plant species are present, how they develop, which ones dominate, and what effect currently undesirable species have on desired species. When such knowledge is available for all, or at least most of the segments, ecosystem management will become both easier and sustainable. Silviculture research can provide some of this knowledge. Natural revegetation of a treated brushfield on a poor-quality, ridge-top site in northern California, and planted ponderosa pine seedlings serve as the setting for this study, and provide answers to some of the above questions. The answers pertain only to this particular segment of forest land and to others having a similar environment. The objectives for this 12-year (1967-1978) study were threefold: (1) to identify the plant species on study plots and denote changes in species richness during the study period$ (2) to quantify density, foliar cover, and height of principal shrubs, and density and height of abundant forbs, ferns, and grasses$ (3) to quantify foliar cover and height of ponderosa pine seedlings, denote their recovery from several forms of damage, and determine their interaction with shrubs in three initial density categories of light, medium, and heavy shrubs.