We gathered baseline data to assess alder tree damage in western Oregon riparian ecosystems. We sought to determine if Phytophthora-type cankers found in Europe or the pathogen Phytophthora alni subsp. alni, which represent a major threat to alder forests in the Pacific Northwest, were present in the study area. Damage...
In coastal forests of the Pacific Northwest, young coniferous plantations typically contain a mixture of planted and natural Douglas-fir (Pseudotsuga menziesii) and western hemlock (Tsuga heterophylla). Swiss needle cast (SNC) disease inhibits the growth of Douglas-fir to varying degrees in these stands, depending on SNC severity. In addition to the...
Alerts people who visit, live, or work in certain areas of Oregon and California about a serious plant disease called Sudden Oak Death, and asks them to take steps to prevent spreading the disease. Gives action steps, shows disease symptoms on various host plants, and gives numerous sources for more...
Swiss needle cast (SNC) severity in Douglas-fir (Pseudotsuga menziesii) has been shown to vary spatially and temporally in response to climatic factors both within its native range and in regions where it has been planted as an exotic species. Survival models were developed for different Douglas-fir needle cohorts to enhance...
Swiss needle cast, a foliar disease caused by the Ascomycete Phaeocryptopus gaeumannii (T. Rohde) Petr., continues to afflict Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) in north coastal Oregon. Permanent plots were installed in 1998 to assess growth impacts and monitor disease severity. Gross periodic annual increment was measured for three 2-year...
This book provides an illustrated guide to the identification and management of fungi, insects, and abiotic conditions that cause problems in Northwest bareroot conifer nurseries. A key to nursery pests offers initial guidance in identification. Separate chapters address individual pests with details on recognition, damage cycle, and management practices to...
Published October 1995. A More recent revision exists. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Published October 1995. Reviewed September 2014. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
A thorough introduction to disease pathogens, signs and symptoms, and management. Nine chapters cover root diseases (Armillaria, annosus, etc.); stem decays (Indian paint fungus, red ring rot, etc.); rust diseases (stem rusts, broom rusts, etc.); other fungal diseases; mistletoes; abiotic diseases; and effects of forest practices such as thinning on...
Sudden Oak Death is the common name for a disease caused by Phytophthora ramorum, a previously unknown and recently introduced non-native pathogen.
• Phytophthora ramorum has killed hundreds of thousands of oak and tanoak trees in 14 coastal counties in California and hundreds of tanoak trees in Curry County, Oregon....