Long-term performance of sudden oak death management treatments in northern California locations

Abstract

Sudden oak death (SOD), caused by Phytophthora ramorum, was first diagnosed as the cause of a lethal canker disease of coast live oak (Quercus agrifolia), California black oak (Q. kelloggii), and tanoak (Notholithocarpus densiflorus) in 2000. Between 2005 and 2009, we initiated multiple field studies to test strategies for reducing SOD impacts in stands of tanoak and susceptible oaks. In oak forests, California bay laurel (Umbellularia californica) is the primary source of P. ramorum inoculum that infects oaks, and proximity to bay greatly increases disease risk (Swiecki and Bernhardt 2008). We evaluated the effectiveness of removing California bay, either on an area-wide basis or locally around individual oaks, on the development and progress of SOD in coast live oak, Shreve oak (Q. parvula var. shrevei), and canyon live oak (Q. chrysolepis).

Parent Publication

• Proceedings of the seventh sudden oak death science and management symposium: healthy plants in a world with Phytophthora

Citation

Swiecki, Tedmund J.; Bernhardt, Elizabeth A. 2020. Long-term performance of sudden oak death management treatments in northern California locations. In: Frankel, Susan J.; Alexander, Janice M., tech. cords. Proceedings of the seventh sudden oak death science and management symposium: healthy plants in a world with Phytophthora. Gen. Tech. Rep. PSW-GTR-268. Albany, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station: 14-18.