Top-kill of ponderosa pine, Dixie National Forest, Utah /

Abstract

Two 320-acre parcels were surveyed on the Escalante Ranger District, Dixie National Forest, UT, to determine the incidence, cause, and impact of top-killed ponderosa pine. Pityophthorus confertus was identified as the causal agent injuring from 1.25 to 2.8 trees per acre. The major impact was loss of height growth, which averaged 2.5 to 4 feet per tree.