Swiss needle cast (SNC) is a fungal disease of Douglas-fir
(Pseudotsuga menziesii) that has recently become prevalent
in coastal areas of the Pacific Northwest. We used growth
measurements and stable isotopes of carbon and oxygen in
tree-rings of Douglas-fir and a non-susceptible reference
species (western hemlock, Tsuga heterophylla) to evaluate...
Abstract: A series of 23 thin, mostly mud-silt turbidites are found interspersed between larger, well-dated and regionally correlated paleoseismic sandy turbidites that extend along most of the Cascadia margin, northwestern United States. Investigation of the structure, distribution, and sedimentology of these thin mud-silt units supports the interpretation of these units...
We modeled patch occupancy to examine factors that best predicted the prevalence of four functionally important focal stream consumers (Tallaperla spp., Cambarus spp., Pleurocera proxima, and Cottus bairdi) among 37 reaches within the Little Tennessee River basin of the southern Appalachian Mountains, USA. We compared 34 models of patch occupancy...
Headwater riparian areas occupy a large proportion of the land base in Pacific Northwest forests, and thus are ecologically and economically important. Although a primary goal of management along small headwater streams is the protection of aquatic resources, streamside habitat also is important for many terrestrial wildlife species. However, mechanisms...
Lower order, non-fish-bearing streams, often termed ‘‘headwater streams’’, have received minimal
research effort and protection priority, especially in mesic forests where distinction between riparian
and upland vegetation can be subtle. Though it is generally thought that breeding bird abundance is
higher in riparian zones, little is known about species distributions...
We examine the relation between δ¹⁸O in rainwater collected in southwestern Oregon
and climate variables including temperature, parcel trajectory, precipitation amount, and
specific humidity. Local surface air temperature at the time of sample collection explains a
large proportion of δ¹⁸O variability, suggesting that paleoclimatic archives that are related
to rainfall...
Swiss needle cast (SNC), an important fungal disease of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), has increased in severity throughout its natural and introduced range over the last half century. The role of climate change and forest management practices in the increase is unclear. We analyzed tree-ring chronologies from six late-successional...
Chlorophyll-temperature profiles were measured across Lake Tahoe about every 10 days from April through July 1980. Analysis of the 123 profiles and associated productivity and nutrient data identified three important processes in the formation and dynamics of the deep chlorophyll maximum (DCM): turbulent diffusion, nutrient supply rate, and light availability....
In early August 2014, the municipality of Toledo, OH (USA) issued a ‘do not drink’ advisory on their water supply directly affecting over 400,000 residential customers and hundreds of businesses (Wilson, 2014). This order was attributable to levels of microcystin, a potent liver toxin, which rose to 2.5 μg L⁻¹...
The management of federal forest lands in the Pacific Northwest (PNW) region changed in early 1990s when the
Northwest Forest Plan (NWFP) was adopted with the primary goal to protect old-growth forest and associated
species. A major decline in timber harvest followed, extending an earlier downward trend. The historic and...