Small Unmanned Aircraft Systems (sUASs) equipped with optical sensors are capableof remotely sensing landscapes and wildlife at spatial and temporal resolutions that werepreviously inaccessible due to technical and budgetary limitations. Conventional remotesensing and photogrammetric workflows can be applied to the resulting high resolution imageryto facilitate new types of scientific inquiry....
Douglas-fir (Pseudotsuga menziesii) is a commercially and ecologically important tree species native to western North America. The foliar pathogens Phaeocryptopus gaeumannii, the causal agent of Swiss Needle Cast, and Rhabdocline species, the causal agents of Rhabdocline needle cast, are two important pathogens specific to Douglas-fir. These pathogens are highly influenced...
Understanding the mechanisms of disease in forest pathology is a critical component to learning how to most efficiently manage tree diseases like Swiss needle cast (SNC). SNC is an economically important, fungal disease of Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) that is prevalent in coastal areas of the Pacific Northwest. This...
This study was directed to improve our understanding of the ecology of Swiss needle cast (SNC) of Douglas-fir, a disease that produces extensive damage to forests and plantation in the coastal region of Oregon and Washington. A disease prediction model for the coastal area of Oregon was built by establishing...
A hierarchical series of studies, based mainly on molecular data, was conducted to elucidate the life history of the Douglas-fir Swiss needle cast pathogen Phaeocryptopus gaeumannii at macro- and micro-evolutionary scales. This information was then utilized to design and evaluate molecular diagnostic tools for use in studies on the epidemiology...
What is it?
Swiss needle cast of Douglas fir is a foliage disease caused
by the fungus Phaeocryptopus gaeumannii. The disease is
specific to Douglas-fir, affecting no other tree species.
A series of studies, in three western Oregon Douglas-fir plantations, was conducted to understand the physiological impacts of Swiss needle cast on Douglas-fir physiology. Four aspects of the disease complex were investigated: fungal colonization and assessment, plant-water relations, carbon assimilation and interaction with climate. Several techniques were developed and used...
A series of studies and replicated field sites were implemented in the Oregon Coast Range within Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) sapling plantations infected with varying levels of Swiss needle cast (SNC) caused by the fungus, Phaeocryptopus gaeumannii (Rhode) Petrak (PG). This research was conducted to understand the effects of...
The relationship between the level of Phaeocryptopus gaeumannii (Rohde) Petrak colonization and severity of Swiss needle cast (SNC) symptoms, the possibility of early testing of Douglas-fir (Pseudotsuga menziesii var. menziesii [Mirb.] Franco) for SNC tolerance, and geographic variation in coastal Oregon with respect to SNC tolerance were investigated. Comparisons between...
Plants respond to defoliation in many different and complex ways, depending on their growth habit and form as well as the extent and duration of the defoliation. Tree crowns have been shown to be quite sensitive to disturbances such as defoliation, however quantitative relationships have rarely been developed, making the...
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CHAPTER THREE: SWISSNEEDLECAST AND DOUGLAS-FIR CROWN STRUCTURE
AND MORPHOLOGY IN THE OREGON