This study was initiated in 1984 to determine the feasibility of using cattle under operational conditions to enhance growth of ponderosa pine (Pinus ponderosa Laws) and Douglas-fir (Pseudotsuga menziesii) seedlings on a southwest Oregon plantation. For ponderosa pine, little differences in predawn xylem potentials during 1984 were detected among the three levels of competition (ungrazed, grazed, and no competition environments). For Douglas-fir, seedlings on the ungrazed plots exhibited significantly more negative predawn xylem potentials earlier in the growing season in comparison to the grazed and no competition treatments. Comparison of both ponderosa and Douglas-fir in 1986 between grazed and ungrazed treatments revealed significantly less negative predawn potentials and greater stomatal conductance on grazed plots early in the grazing season. Results of this research lend support to the hypothesis that appropriately timed grazing can improve the availability of soil moisture and ultimately benefit the vigor and growth of tree seedlings. A key finding of this case study was increased conifer growth and vigor in the grazed treatment.
Citations and enhanced abstracts for journals articles and documents focused on rangeland ecology and management. RSIS is a collaboration between Montana State University, University of Idaho, and University of Wyoming.