The epiphytic lichen Letharia vulpina has been commonly sampled in-situ for nitrogen (N) deposition biomonitoring studies but has never before been transplanted for this purpose. In the high-elevation wilderness areas of southern California Letharia vulpina is generally uncommon, making in-situ sampling difficult. In this study, we compared thallus N accumulation...
Anthropogenic induced climate change is predicted to alter distribution of existing plant populations. As plants migrate over space and time, populations often fragment and contract, affecting basic elements of population dynamics (e.g., population size, gene flow, genetic diversity, etc.). Little is known, however, how these impacts on plant species will...
Oomycete and fungal pathogens threaten food, fiber, and forests around the world. With climate change, these pathogens are expected to emerge more frequently. Evolution can facilitate their emergence through mechanisms such as mutations that change or expand host range. Characterizing evolutionary mechanisms in plant pathogens will contribute to our ability...
Within the Pacific Northwest, USA, root diseases of conifers are a major forest health concern. These diseases are primarily caused by basidiomycete fungi. These fungal associates play a vital role in carbon sequestration but also have a significant negative economic impact within the timber industry. As a result, research on...
Sudden oak death is caused by the clonally reproducing generalist oomycete Phytophthora ramorum. The pathogen can infect more than 130 different plant hosts including Quercus spp., Larix kaempferi, and Notholithocarpus densiflorus, as well as common nursery genera such as Rhododendron and Camelia, where it causes symptoms ranging from bleeding cankers...
In recent years, our ecological knowledge of tropical dry forests has increased dramatically. However, whole components of the ecosystem, like lichenized fungi, remain mostly unknown. Crustose lichens in these forests are so abundant, that they are responsible for the characteristic appearance of a “white bark forest” during the dry season....
Wetland prairies of the Willamette Valley, among the rarest of Oregon’s ecosystems, are threatened by invasion of woody species and non-native pest species. Because fire has been important in maintaining Willamette Valley prairies for at least 1000 years, prescribed burning is a top choice of managers for preventing encroachment of...
Wetland prairies of the Willamette Valley, among the rarest of Oregon’s ecosystems, are threatened by invasion of woody species and non-native pest species. Because fire has been important in maintaining Willamette Valley prairies for at least 1000 years, prescribed burning is a top choice of managers for preventing encroachment of...
The Pacific Northwest is an internationally important region for the production of Brassica seed and other seed crops including grass seed. Oregon lawmakers mandated research into the co-existence of canola (Brassica napus) with other Brassica production in the Willamette Valley and House Bill 2427 was signed into law in 2013,...
Rhizopogon is a large genus of ectomycorrhizal (EM) fungi that grows in association with host trees of the family Pinaceae. We have conducted a series of studies investigating the ecology and evolutionary biology of the EM symbiosis shared between R. subgenus Villosuli and trees of the genus Pseudotsuga. Two members...