Brush Reduces Growth of Thinned Ponderosa Pine in Northern California

摘要

The effects of tree spacing and brush competition were evaluated on a ponderosa pine (Pinus ponderosa) site of low productivity in California's North Coast Range. Eleven year old saplings were thinned to square spacings. Analysis of variance showed that brush crown cover was significantly related to periodic annual increment in diameter-at-breast-height, height, and volume of the pines. Spacing significantly influenced diameter growth only when all brush was removed.