Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Non-oak native plants are main hosts for sudden oak death pathogen in California.

Abstract

Experiments conducted during 2001 and 2002 identified 13 additional species from 10 plant families as hosts for Phytophthora ramorum (the causal organism of sudden oak death) throughout its range in forests of California, USA. These species were: Umbellularia californica, Acer macrophyllum, Quercus kelloggii, Aesculus californica, Quercus agrifolia, Sequoia sempervirens, Rhamnus californica, Pseudotsuga menziesii, Vaccinium ovatum, Arbutus menziesii, Arctostaphylos manzanita, Lithocarpus densiflorus and Heteromeles arbutifolia. Pathogenicity tests showed that symptoms of Phytophthora ramorum occur on aboveground parts, such as leaves, branches and stems, regardless of the host.