Water polluted by pharmaceuticals, metals, and phosphates can be hazardous to both the environment and human health. The main aim of this study is to develop low cost, green adsorbents for removal of these pollutants from aqueous solution as a low cost alternative to activated carbon. Biochar was produced from the fast pyrolysis of Douglas fir. Magnetic biochar was prepared by magnetite (Fe3O4) precipitation onto the biochar’s surface from an aqueous Fe3+/Fe2+ solution upon NaOH treatment. Both Douglas fir and magnetic Douglas fir biochars have high uptake and adsorption capacity. Chapter I provides an overview of different biochar production techniques and modification methods. Chapter II is a study of the aqueous adsorption of pharmaceutical products, 4-nitroaniline (4NA), salicylic acid (SA), benzoic acid (BA) and phthalic acid (PA) using Douglas fir and magnetic Douglas fir biochar. The surface chemistry and composition of the magnetic biochar were examined by SEM, SEM-EDX, TEM, PZC, XPS, XRD, elemental analysis, and surface area measurements. Chapter III describes the removal of lead and cadmium using both magnetic and nonmagnetic Douglas fir biochar and Chapter IV describes the removal of phosphate from waste water. In Chapter V, this low cost adsorbent (magnetic Douglas fir biochar) was introduced into an undergraduate laboratory to expose students to water quality issues and methods of contaminant removal enhancing their understanding of these important environmental issues. This experiment introduces new and interesting approaches to water purification as well as deepens the student’s understanding of present environmental concerns regarding pharmaceutical contaminants in wastewater.

Molybdenum (Mo) is a naturally occurring trace element that is present in drinking water mostly in the molybdate (MoO42-) form in well water. Recently, the EPA deemed Mo as a potential contaminant because exposure can lead to health effects such as gout, hyperuricemia, and lung cancer. In this work, we have assessed the sorptive removal of Mo using Douglas fir biochar (DFBC) and its chemically-coprecipitated iron oxide analogue (DFMBC). Adsorption was studied varying the batch sorption conditions; pH, equilibrium time (5 min-24 h), initial Mo concentrations (2.5-1000 mg/L), temperatures (5, 25, and 40 °C) and equilibrium method. Langmuir capacities for DFBC and DFMBC (at pH 3, 2 h equilibrium) were in 359.3-487.9 mg/g and 288.3-571.9 mg/g range, respectively. Adsorbents and Mo-laden adsorbents were characterized by elemental analysis, BET, PZC, SEM, TEM, EDS, XRD, and XPS. These data suggest that DFBC and DFMBC can be potential candidates for Mo sorption.

The purpose of this study was to find out if ecological races with different growth rates existed in douglas fir. Seeds were collected from six areas by the Forest Service and the author. A study was made of stem and tap root growth utilizing three photoperiods of varying length. Rate of tap root growth was significant for ecotype suggesting selection for tap root length in the plants from utah and Arizona. Each geographical area represents a growth rate ecotype with a wide break in the data on stem growth.

Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 93-100). Also available on the World Wide Web.

Data on rates of atmospheric deposition is limited in many montane ecosystems, where high spatial variability in meteorological, topographic, and vegetation factors contributes to elevated atmospheric inputs and to the creation of deposition hotspots. Addressing the ecological consequences of increasing deposition in these areas will require a better understanding of surface controls influencing atmospheric deposition rates at both large and small-scales. The overarching objective of this thesis research was to understand the influence of vegetation structure and canopy exposure on small-scale patterns of atmospheric sulfate, nitrate, and chloride deposition inputs to a conifer forest in the Santa Cruz Mountains, California. Throughfall ion fluxes (i.e., ions delivered in water that pass from the forest canopy to the forest floor), bulk deposition (i.e., primarily wet deposition), and rainfall data were collected during the rainy period from October 2012 to May 2013. Throughfall SO42-, Cl-, and NO3- fluxes were measured beneath eight clusters of Douglas fir (Pseudotsuga menziesii) trees (three trees per cluster) differing in tree size (i.e., diameter at breast height; DBH) and canopy exposure. In each cluster, a throughfall collector was placed 1-meter from the bole of an individual tree, for a total of 24 individual collectors. The position of each throughfall collector was recorded with a Trimble® GPS. In addition, tree height, tree diameter, and leaf area index, were measured for all trees. LiDAR data were obtained from GeoEarthScope’s Northern California Airborne LiDAR project and used to model the elevation (DEM), canopy surface height (DSM), tree height (CHM), slope, and curvature of the canopy surface across the entire study area. Over the rainy season, total throughfall flux of SO42--S, a conservative tracer of total deposition (wet + dry + fog), to Douglas fir clusters ranged from 1.44 - 3.84 kg S ha-1 wet season-1, while dry and fog deposition ranged from 0.13 -2.37 kg S ha-1 wet season-1. Total deposition to exposed mature tree clusters was 1.7-2.7 times higher than other clusters. Patterns of total Cl- fluxes (17.10 – 54.14 kg Cl- ha-1 wet season-1) resembled patterns of total SO42--S inputs. Overall, net throughfall fluxes (throughfall – bulk deposition) to Douglas fir trees clusters were more variable than total throughfall fluxes. Net SO42--S and Cl- fluxes to individual collectors increased with tree DBH and the convexity of the canopy surface. Compared to SO42--S and Cl- in throughfall, total NO3--N fluxes (0.17 - 4.03 kg N ha-1 wet season-1) were low and appeared to vary with small-scale changes in elevation. Geospatial technologies and remote sensing tools, such as LiDAR, are promising in the study of relationships between atmospheric deposition and topography (including vegetation), and in scaling-up estimates of atmospheric deposition to larger spatial scales. Understanding small-scale surface controls on atmospheric deposition has implications for different areas of research within geography, including modeling the spread of emerging infectious disease and assessing the effects of nitrogen cycling on native and invasive plant species composition.

Low embodied energy, ability to act as a carbon store and ease of recycling gives forest products an important role within a low carbon built environment. Almost 25 % of the coniferous resource within the South West of England is Douglas-fir, a species reputed for producing high quality timber. Despite this, the region is facing challenges in delivering the resources full potential, a contributing factor to which is a loss of knowledge regarding its quality. The aim of the work presented is to gain an improved understanding of the quality of Douglas-fir grown within the region, from the perspective of uses in structural applications, the factors which influence material quality and their interrelationships. Flexural modulus of elasticity, flexural and compressive strength were determined utilising small clear specimens derived from 1.3 and 8 m heights within 27 trees from six sites across the South West. Results showed a rise in the magnitude of properties with increasing cambial age, particularly so at younger ages. Differences in values were also recorded between stem heights and with rate of growth. These were however less than age related variations. Results compared favourably to those reported in other studies conducted on the species. Utilising SilviScan-3, anatomical properties including density, microfibril angle and cellular dimensions were measured. Significant variations were recorded with cambial age, and in some instances sampling height. The influence of growth rate on anatomical properties was small. Through statistical and composite modelling, microfibril angle was found to be strongly associated with changes in modulus of elasticity within juvenile wood. Within mature wood and for strength properties, density was the controlling factor. It was shown that a moderate proportion of variations in mechanical properties can be accounted for utilising visually identifiable wood characteristics. The new understanding that has been gained through this work presents opportunities for improved utilisation, the implementation of effective management practices and the development of more efficient visual grading techniques.

"The Wildland/Urban Interface, in which homes are intermingled with forested areas, presents unique challenges to fire protection and fire prediction, owing to the different fuel loads, conditions, and terrain. Computer models that predict fire spread through such an area require data for multiple scales, from crown fire spread to the heat release rates and ignition conditions for individual trees, as well as an understanding of fire behavior and spread. This discussion investigates a means by which fire behavior for Douglas-fir trees can be determined from quantifiable characteristics, such as height and moisture content. Mass, flame height, peak heat release rate, and total energy can be estimated from these simple measurements. A time scale of 60 seconds, combined with a peak heat release rate estimated from tree size characteristics, provides an approximation of total energy that is within 11% of measured values. Pre-heating of trees with a low (2.5 kW/m2) radiant heat flux did not have a noticeable impact on the resulting heat release rate. In addition, fire spread between trees was highly dependent on the presence of ambient wind; in the absence of wind or wind-borne embers, the trees were very resistant to ignition even when in close proximity (3 spacing). With the addition of wind, the fire would spread, although the heat release rates were dramatically reduced for trees of sufficiently high moisture content (< 70%)."

The western spruce budworm, Choristoneura occidentalis Freeman (Lepidoptera: Tortricidae), is a serious defoliator of conifers in the western U.S. and western Canada. In 1985 epidemic levels of the budworm caused average tree defoliation in west-central Idaho to increase to 83%, up substantially from the 35% average tree defoliation of 1984. Associated with this increase in defoliation was a change in the relative stand defolation ranking between the two years. found to damage all types and In 1985 the budworm was developmental stages of reproductive structures of Douglas- fir, including: seedcone buds, pollen-cones buds, maturing cones, and seeds. Differential selection of feeding sites was observed, with a significantly higher proportion of larvae found in seedcone buds than in pollen-cone buds. Shortly after larval emergence, 25% of the total number of seed-cones buds were infested. A subsample of 171 branch tips indicated that only 9% of pollen-cones, while less than 2% of the vegetative buds contained larvae. A total of 640 cones from 21 trees were examined. Of these cones, 76% were infested with larvae, however not all of the seeds were destroyed. The average percent of destroyed seeds per tree was found to be exponentially related to the average current defoliation of the tree.

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 of a Swiss needle cast outbreak near Tillamook, Oregon. Phylogenetic analyses of partial nuclear ribosomal gene sequences indicated that P. gaeumannii, currently classified in the Venturiaceae, is closely related to neither Phaeocryptopus nudus, type of the genus, nor Venturia inaequalis, type of the Venturiaceae. Instead, it is closely related to members of the "sooty molds" (Capnodiales), particularly the common and morphologically similar Douglas-fir epiphyte Rasutoria pseudotsugae (Euantennariaceae). Single-strand conformation polymorphisms, revealing DNA sequence variation in five loci, were used to investigate population biology of P. gaeumannii from a worldwide collection of isolates. In western Oregon, P. gaeumannii population structure suggests a predominantly selfing reproductive mode within two reproductively isolated sympatric lineages. One lineage was widely distributed both locally and abroad. The second lineage was restricted to western Oregon and suggested a correlation with symptoms of Swiss needle cast. A novel application of real-time PCR allowed species-specific detection and quantification of P. gaeumannii and proved a good measure of its biomass in Douglas-fir needles. Compared to other techniques (ergosterol and a DNA probe), real-time PCR correlated best with visual estimates of needle colonization and additionally proved useful early in the first year of the colonization process before visible development of fruiting structures. While all four methods provided evidence that sites expressing a range of disease severity differed in the degree of fungal colonization, only real-time PCR consistently separated both moderately and severely diseased sites from relatively healthy sites. Seedling inoculation experiments, fulfilling Koch's postulates, demonstrated that P. gaeumannii is the causal agent of Swiss needle cast, as observed in the Tillamook epidemic. Furthermore, the incorporation of virulence tests provided independent, non-molecular evidence that Oregon's pathogen population is not homogeneous. One strain, isolated from a severely diseased site, caused significantly greater symptom severity than strains derived from less damaged sites. / Graduation date: 2002

In terms of production forestry, more often than not any species that is not the crop species is considered a competitor as they are using finite growing resources that would otherwise be available to the crop species. With specific regard to Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) production in the Pacific Northwest, this study evaluated an array of morphological and physiological plant attributes to discern the relative competitive abilities of several common forest species and planted Douglas-fir in western Oregon during the first year of plantation establishment in the presence and absence of vegetation management treatments. The competitive ability of a species refers to the morphological and physiological characteristics associated with resource acquisition and internal allocation; a concept lacking a specific metric for evaluation. A conceptual model of plant resource utilization including proxy metrics for key aboveground plant-environment interactions was used a framework for synthetic assessment of species relative competitive ability. The relative competitive abilities of species were evaluated over a summer growing season with assessments of saturated specific leaf area (SLA[subscript SAT]) and saturated leaf dry matter content (LDMC[subscript SAT]), diurnal and seasonal leaf-level gas exchange (net photosynthesis (P[subscript n]), stomatal conductance (G[subscript s]), and derived instantaneous water-use efficiency (WUE)), midday leaf xylem pressure potential (��[subscript md]), aboveground proportional allocation of biomass into stem, leaf, and reproductive body components, leaf area index (LAI), and morphological development and growth (height, crown radius, and diameter and bud density for Douglas-fir). The study employed a complete randomized block design (RCBD) with four replicates (blocks) and three vegetation management treatment regimes: untreated control (C), site preparation only (SP), and site preparation with a spring and summer release (SP+R). The relative competitive ability of all species was evaluated in the C, whereas only dominant competitor species remained for evaluation in the SP treatment. Vegetation treatment effects were evaluated among remaining competitor species and Douglas-fir in the C and SP treatments, whereas the response of Douglas-fir was assessed across all three vegetation management treatments (C, SP, SP+R). Selected forest competitor species included two woody perennial shrubs, two ferns, one herbaceous dicot, and two herbaceous graminoid species: trailing blackberry (Rubus ursinus Cham. & Schlecht), snowberry (Symphoricarpos albus (L.) Blake), swordfern (Polystichum munitum (Kaulfuss) K. Presl), bracken fern (Pteridium aquilinum (L.) Kuhn), woodland groundsel (Senecio sylvaticus L.), California brome (Bromus carinatus Hook. & Arn.), and false brome (Brachypodium sylvaticum (Huds.) Beauv). Forest competitor species evaluated in the SP treatment were limited to trailing blackberry, swordfern, woodland groundsel, and California brome. Species relative competitive ability varied dramatically. However, similarities related to herbaceous and woody life forms were observed. Based on both univariate and multivariate response variable analyses, the relative competitive abilities of species examined in the study were ranked as follows: woodland groundsel > false brome > California brome > trailing blackberry = bracken fern > snowberry > swordfern > Douglas-fir. Although vegetation treatments effectively reduced total cover below 20%, a threshold of putative importance, with observed effects on soil moisture content and species performance, species relative competitive ability remained unchanged. Physiological responses were more variable than morphological responses for species performance and expressed greater sensitivity to vegetation treatment. Vegetation treatment effects were most pronounced for Douglas-fir in the SP+R treatment where mean total cover was 6.5%. In the SP+R treatment Douglas-fir exhibited decreased moisture stress coupled with significant increases in both diurnal and seasonal P[subscript n] and G[subscript s] rates and patterns. / Graduation date: 2013