Pruning reduces blister rust in sugar pine with minimal effects on tree growth
Kevin O'Hara, Department of Environmental Science
Lauren A. Grand, Department of Environmental Science
Amy A. Whitcomb, Department of Environmental Science
California Agriculture 64(1):31-36. DOI: 10.3733/ca.v064n01p31.
Sugar pine trees from nine stands in two California study areas were assessed to determine the effects of pruning on the incidence and growth of white pine blister rust. Lower limbs up to 8 feet high were removed on alternate trees. Six years following treatment, the number of infections in pruned trees was reduced compared to unpruned trees at one study area, but no blister rust was found at the other area. The results suggest that artificial pruning of sugar pine may be part of an effective, integrated strategy to maintain this species in mixed-conifer California forests.
K.L. O'Hara is Professor of Silviculture, Department of Environmental Science, Policy and Management, UC Berkeley; L.A. Grand is Recent Graduate, Department of Environmental Science, Policy and Management, UC Berkeley; A.A. Whitcomb is former Graduate Research Assistant, Department of Environmental Science, Policy and Management, UC Berkeley.
The authors acknowledge the assistance of those at Blodgett Forest Research Station, particularly Robert Heald and Robert York. Roseburg Forest Products and Sierra Pacific Industries provided access to the Lake Almanor field sites. Analise Elliot, Rolf Gersonde, Bruce Hammock, Patricia Peraino, Mark Spencer, Tudor Stancioui, Zachary Thomas and Rebecca Wilcox provided field assistance. John Battles, Associate Professor, Department of Environmental Science, Policy and Management, served as Guest Associate Editor for this article.