The brine shrimp (Artemia salina) bioassay was used to screen 211 methanol extracts from 128 species of Pacific Northwest plants in search of general cytotoxic activity. Strong toxicity (LC₅₀ < 100 µg/ml) was found for 17 extracts from 13 species, with highest activity observed for Angelica arguta roots at <10...
Phellinus sulphurascens (previously the Douglas-fir form of Phellinus weirii) is an important native pathogen causing laminated root rot in forests of western North America. Visual crown symptoms, or attacks by bark or ambrosia beetles appear only during advanced stages of the disease with extensive infection in the lower bole. Ethanol...
Key message Leyland cypress, an intergeneric hybrid, produces the same volatile heartwood compounds as its parental taxa, yellow-cedar and Monterrey cypress. However, the proportion of total sesquiterpenes and some of the individual components appear unique to their respective heartwoods.
Context Leyland cypress, xHesperotropsis leylandii is an intergeneric hybrid between yellow-cedar,...
Ethanol in sapwood was analyzed along vertical transects, through small spot cankers and larger basal cankers, of Phytophthora ramorum-infected stems of Quercus agrifolia at three sites in California. Trees with large basal cankers, known to attract scolytid beetles, had a 4.3 times higher ethanol level than trees with spot cankers...
Diseased and healthy Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) were identified at two black-stain root disease centers, caused by Leptographium wageneri var. pseudotsugae Harrington & Cobb, in the Oregon Coast Range near Coos Bay. Phloem and sapwood near the root collar were sampled monthly for 1 year, whereas roots were sampled...