M.Sc. (Botany) / Global efforts to protect the world’s forests from unsustainable and inequitable exploitation have been undermined in recent years by rampant illegal logging in many timber-producing countries. A prerequisite for efficient control and seizure of illegally harvested forest product is a rapid, accurate and tamper proof method of species identification. DNA barcoding is one such a tool, relatively simple to apply. It is acknowledged to bring about accuracy and efficiency in species identification. In this study a DNA barcode reference library for traded and protected tree species of southern Africa was developed comprising of 81 species and 48 genera. Four primary analyses were conducted to assess the suitability of the core barcodes as a species identification tool using the R package Spider 1.2-0. Lastly, to evaluate this identification tool, query specimens independently sampled at a Mozambican logging concession were identified using DNA barcoding techniques. The nearest neighbour (k-NN) and best close match (BCM) distance based parameter yielded 90% and 85% identification success rate using the core plant barcodes respectively. DNA barcoding identification of query specimens maintained a constant 83% accuracy over the single marker dataset and the combined dataset. This database can serve as a backbone to a control mechanism based on DNA techniques for species identification and also advance the ability of relevant authorities to rapidly identify species of timber at entry and exit points between countries with simple, fast, and accurate DNA techniques.

Site preparation treatments are often used prior to the planting of clearcut forest lands to improve planter access and to increase the number and quality of planting spots. Most mechanical site preparation treatments alter the configuration and material composition of surface soil materials, and can have marked effects on soil properties important to seedling survival and growth. Effects of some of these treatments on soil moisture, soil temperature, rates of nitrogen mineralization, and the establishment of Picea glauca x engelmannii seedlings were examined on fresh, moist, and wet sites in the moist cold subzone of the Sub-boreal Spruce Zone in west-central British Columbia. Four types of microsite alteration were investigated: forest floor removal (spot scalping), soil mounds over inverted sections of forest floor (inverted mounds), mineral soil mounds over a mineral soil surface, and inversion of the forest floor and mineral soil in place. Soil temperature was monitored continuously and soil moisture weekly at the 10-cm depth in 16 combinations of site and microsite treatment during two growing seasons. The response of seedling height and diameter growth was monitored for three growing seasons. Effects of altering soil temperatures through mechanical treatments on rates of nitrogen mineralization were examined by incubating a standard soil material in a range of microsites created by six combinations of site and mechanical treatment. Effects of substrate quality and soil temperature on rates of nitrogen mineralization were examined in paired mounded and untreated spots in fresh, moist, and wet sites. In all sites, early growing season soil temperatures in the seedling rooting zone were substantially warmer in inverted mounds than in other treatments. Spot scalping increased temperatures slightly relative to controls in the fresh site, but had little or no warming effect on moist and wet sites. Inverted mounds became substantially drier than other treatments during periods of low rainfall, particularly in the fresh site. After three growing seasons, seedling height growth was greatest in inverted mounds, irrespective of site. Amounts of nitrogen mineralized in a standard soil material during incubation for 77 days in the field were significantly greater for samples placed in inverted mounds than for those placed in other microsite treatments. There was a significant positive correlation between amounts of nitrogen mineralized during field incubations and degree hour sums calculated for associated microsite treatments and sites. Both substrate quality and soil thermal regime affected rates of N mineralization in samples from paired mounded and untreated spots, and an interaction was observed between the two factors. / Graduation date: 1991

Thesis (M.S.) in Ecology and Environmental Science--University of Maine, 2009. / Includes vita. Includes bibliographical references (leaves 78-87).

Thesis (Ph. D.)--Oregon State University, 2009. / Printout. Includes bibliographical references. Also available on the World Wide Web.

The sustained-yield policy presently practiced in British Columbia necessitates intensive management of forest land especially in the coastal region of the province. Soils, their nature and distribution, provide an ideal framework for a successful implementation of such management. A mapping system encompassing geology and soil and providing units interpretable for forestry practices was developed for the coastal forested lands of British Columbia. The system contains several steps of mappings corresponding to different intensities or levels of abstraction. These levels are: 1. Bedrock geology, 2. Surficial geology, 3. Geologic units, 4. Geologic unit - drainage classes, 5. Soil associations, and 6. Soil catenas. Mapping employs air-photo interpretation extensively and can be directly undertaken at any desired level for inventory of interpretation purposes. Grouping of units can also be made from any level of mapping. Maps showing the distribution of bedrock types, surficial materials and soils were prepared. Vancouver volcanics, Coastal intrusives and Cretaceous sandstones are the main bedrock formations. The surficial materials encompass the inter-glacial, glacial, post glacial and recent deposits, and consist of glacial tills, glaciofluvial, alluvial and marine sediments. The soils encountered represent the Podzolic, Brunisolic, Regosolic, Gleysolic and Organic Orders. The area is comprised of primarily Douglas-fir plantation, 20 to 30 years of age. Studies involving the soil-stand growth relationship were undertaken on the well drained soils developed on the major surficial materials. Morphological, physical, chemical and minera1ogica1 characteristics of soils and the growth statistics of stands were determined. The growth performance of Douglas-fir varied with the kind of soil. Growth was best on soils developed from marine clay. Soils developed from stony outwash exhibited the slowest growth and lowest productivity. Till soils had productivity between these two extremes. The textural components of soil (coarse sand, medium sand, total sand, total silt, coarse clay, fine clay and total clay), were correlated to growth. With respect to chemical nutrients, organic matter, calcium and magnesium, phosphorus and zinc appeared to be important factors. The soil moisture retention characteristics such as field capacity and available water showed correlation with growth. The relationship between the growth and soil characteristics became more apparent as stand age advanced. Interpretation of soil series and mapping units at different levels was carried out for: productivity for Douglas-fir, species suitability, logging hazard, slash burning hazard, natural regeneration probabi1ity, brush hazard, browsing hazard, thinning prescription, fertilizer recommendation, road construction suitability, and erosion. Two groupings, potential productivity and thinning recommendation for Douglas-fir, were undertaken. The study indicated that knowledge of soils and their distribution are prerequisite to the operational and economical management of forest and soil resources. Consequently, a classification scheme such as the one presented is the first and essential step towards the intensive management of the coastal forested lands in British Columbia. / Land and Food Systems, Faculty of / Folded map and table in back pocket. / Graduate

Two studies were designed to test three herbicides and factors which influence their efficacy. In the first study four chemical combinations used for site preparation in southern pine, including triclopyr (3,5,6-trichloro-2-pyridinyloxyacetic acid), trichloropicolinic acid), dichlorophenoxy)acetic acid] picloram (4-amino-3,5,6- and 2,4-D [(2,4- were screened for the most effective control of selected hardwoods. The chemical combinations were tested on Piedmont and Coastal Plain physiographic sites and were examined for the optimum amount of time for chemical activity between application and slash disposal (site disturbance). Efforts were also made to use target-plant and environmental data to predict chemical efficacy. A combination of triclopyr and picloram at 2 and 1 lb ai/ac, respectively, each gave the best overall control of hardwood brush. The amount of time required to obtain the optimum chemical control, presumably related to translocation, was found to be six to eight weeks after application to the foliage. Chestnut oak (Quercus prinus L.) control was successfully predicted on the bases of plant tissue and environmental data. In a second study the effect of temperature and time on the distribution of foliar-applied triclopyr, picloram, and 2,4-D were observed in red maple (Acer rubrum L.). Detection of the herbicides in the stems and roots using gas chromatography revealed that triclopyr was less affected by temperature differences; however, overall more herbicide reached the roots of red maple growing in a 21° C than those growing in a 29° C temperature. Triclopyr concentrations in the roots reached a peak much earlier than picloram or 2,4-D which did not peak until 42 days after application. / M.S.

Equations for modeling the height-age pattern of forest trees or stands are typically developed for a given species in a specified region. In order to adequately model height-age patterns, the resulting equations are often quite complex. This study addresses the question of how to increase the accuracy and precision of the prediction of height-age relationships through the use of localized equations. Although the pattern of height-age relationships of loblolly pine plantations was studied, the methodology should prove valuable for other species as well. The Schumacher logarithm of height-reciprocal of age model was fitted to data from loblolly pine plantations to attain an average guide curve. Various methods of localizing this equation to a particular stand were examined. The methods are based on empirical Bayesian, maximum likelihood, and Kalman filter theory. All of these methods employ the general concept of feedback in localizing the simple equation. The best of these various models is compared with the unadjusted model and a more complex polymorphic equation. The adjusted model compares favorably with these other two models. / Master of Science

The purpose of the study was to define the characteristics of tree-length skidding on the Lower Coastal Plain of Georgia. The objectives were: 1) to document skidder performance based on speed and tire slip, 2) to determine the effects of skidding on soil physical properties, and 3) to develop recommendations to minimize the impact on soil properties while maintaining skidder performance. A Franklin 170 grapple skidder was operated in second gear under moist (19% moisture content) and wet (31% moisture content) soil conditions using 28L-26, 67x34-25, and 73x44-32 tires. One, three, nine, and 27 passes were tested. The skidder was also operated in third gear with the 73x44-32 tires under the wet soil condition. With moist soil conditions skidder speed and tire slip were not affected by tire size or the number of skidder passes. Tire size did not influence soil properties. It was recommended that skidding be dispersed to avoid making more than nine passes over any particular soil area because the research indicated that repetitive passes resulted in a cumulative decrease in non-capillary porosity and an increase in bulk density. During wet conditions, wheel slip increased, skidder speed decreased, and rut formation increased with smaller tires, an increase in the number of skidder passes, and second gear operation. Operating the skidder in third gear with the 73x44-32 tires was beneficial to skidder performance and a reduction in rutting. Recommendations were to disperse skidding to maintain productivity and minimize rutting. / Master of Science

Response to fertilization is a function of the degree to which nutrients are limiting growth, the capacity of individual trees to respond to nutrient inputs, the degree to which other factors limit growth, and the possible extrinsic effects of treatment (e.g., root mortality due to fertilizer-induced soil pH effects). Recognition and examination of these factors is essential if response to fertilization is to be predictable. Over the past 25 years numerous western hemlock fertilizer trials have shown responses ranging from negative to positive with no clear trends. Theories for this erratic response include: (a) different nutritional requirements during different stages of stand development; (b) high native N availability or low supplies of other nutrients (P and S, in particular); (c) differential adverse effects of N fertilizers on surface roots, mycorrhizal populations and P nutrition; (d) a requirement for slow release N; and (e) induced water stress. The objective of this study was to develop site-specific guidelines for western hemlock fertilization decision-making for industrial use. This study reports on the first and third growing-season response to two different fertilizer treatments, and identification of possible relationships between fertilizer response and site and stand conditions.

The influence of salal on tree growth has attained considerable attention in coastal British Columbia. Field observations, surveys, and studies in the CWH zone have indicated poor growth performance of crop tree species in salal-dominated plantations and natural immature and old-growth stands. Where sites have been burned and planted, tree growth has improved; similar effects have been observed for naturally regenerated stands. Immature stands that developed after wind disturbance or harvesting feature rapid growth and nearly complete absence of salal. As studies have shown that ericaceous plants negatively impact tree growth, the salal on potential harvest sites has been considered undesirable. This study examined (1) the possible influence of salal on the stand, soil nutrient status and site index, and (2) the relations between site index, salal, plant communities, and site in disturbed, immature, coastal Douglas-fir ecosystems. We compared vegetation and environmental characteristics of 101 ecosystems, and examined differences in foliar and soil nutrient characteristics and site index between stands with high and low salal cover through analysis of variance (ANOVA) and regression analysis.