Controlling competing vegetation with the application of herbicides and increased seedling size at planting has been shown to increase seedling survival and growth. These two important reforestation tools have often been studied independently of each other, limiting comparisons that can be made between them. This study utilized a factorial treatment...
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RobinRose
Controlling competing vegetation with the application of herbicides and
Three studies were conducted to characterize and present early-seral
competition between Douglas-fir seedlings and the surrounding vegetation
communities during Pacific Northwest forest establishment. The first experiment
served as the foundation for this dissertation and was designed to quantify tradeoffs
associated with delaying forest establishment activities by introducing a fallow year...
Ammonia (NH₃) volatilization can result in a substantial amount of surface applied nitrogen (N) being lost into the atmosphere, making it an environmental pollutant as well as reducing plant-available N. However, N can also be easily lost from the soil through leaching,
and nitrous oxide (NO₂). Enhanced efficiency N fertilizers...
Understanding the tradeoff between water use and productivity is critical for modeling growth of intensively managed Douglas-fir forests in the Pacific Northwest. Evapotranspiration is closely linked to carbon dioxide intake during the process of photosynthesis. However, summer drought characterizing the growing season in this region imposes a limit on carbon...
Windthrow has been studied extensively as a cause of mortality and as a landscape
disturbance agent in temperate forests throughout the United States. The effects of
windthrow mortality on stand species composition and structure, forest regeneration and
seral development have been well described at the site (e.g. single gap) and...
The three essays in this dissertation progressively answer the following questions: (a) How important are constraints? (b) Who benefits from removing constraints? (c) When does a constraint for a single market predominantly affect closely related markets? These questions are applied in the context of time, weather, and minimum wage constraints,...
Foresters care about site productivity and stem quality in Douglas-fir plantations for many reasons. The profitability of forest land and the economic returns on silvicultural investments are directly related to site productivity. Thus, understanding the relationships among Douglas-fir productivity, stem form and site characteristics is important economically. My objective was...
This thesis presents the results of an investigation into the interactions between the present-day South Cascade Glacier and the former Mauna Kea ice cap at short (annual to centennial) and long (millennial and multimillennial) time scales. To quantify the response of South Cascade Glacier to atmospheric conditions, a surface energy...
