Thesis--University of Washington. / Vita. Another copy has number: Thesis 27746. Bibliography: leaves [292]-300.

Thesis (M.S.)--Oregon State University, 1985. / Typescript (photocopy). Includes bibliographical references (leaves 69-71). Also available on the World Wide Web.

Thesis (M.S.)--Oregon State University, 1985. / Typescript (photocopy). Includes bibliographical references (leaves 106-107). Also available on the World Wide Web.

Assessing trends in forest ecosystems requires a thorough understanding of a benchmark or condition against which changes can be measured. Timber cruise information is a valuable source of baseline data, and has potential to be used in monitoring the effectiveness of management actions taken to maintain biodiversity and other societal values during and after harvesting. The objective of this study was to assess the efficacy of using these data as baseline information in FREP (Forest and Range Evaluation Program) Stand Level Biodiversity (SLB) assessments. Using three different data sources (timber cruise data, FREP pre-harvest data, and FREP post-harvest data), I conducted a pre- and post-harvest survey and evaluated trends in indicators within and across seven cutblocks. Mean densities for live and standing dead trees by diameter class, total live and dead trees, functional snags, large trees, tree species composition, coarse woody debris, and a number of qualitative indicators were analyzed. Results indicate that similarities exist between several characteristics within the timber cruise and pre- and post-harvest FREP data. For example, there was substantial overlap between stand structural characteristics assessed by the three methods. However, some discrepancies were identified. Large trees (live, dead and live and dead combined) were evident in very small numbers in the timber cruise and data were not consistent with pre-harvest FREP data. The number of tree species identified in FREP data was generally lower than timber cruise data, with the species absent in the FREP data generally being recorded as rare in the timber cruise. Some important stand structural attributes are not collected under the current timber cruise protocol. This research has identified some possible limitations of using timber cruise statistics as baseline information for FREP SLB monitoring. Forests are dynamic, rare forest elements may be misrepresented in all three samples, and some potentially valuable data are currently missing from timber cruise statistics. However, the opportunities that timber cruise data provide as a provincial baseline dataset are immense, and further exploration and study could identify ways to improve the compatibility, efficiency, and utility of these data in FREP Stand Level Biodiversity monitoring. / Forestry, Faculty of / Graduate

Architects use materials to express an idea, give form and create shelter for whatever the reason might be. The architect’s arsenal comprises five main materials: steel, concrete, masonry, glass and timber. When and how these materials are used is dictated by personal preference, public opinion, legislation, environmental aspects and availability. The use of timber in the South African built environment has not taken centre stage, yielding to superior materials such as concrete and steel. Nevertheless, a mass timber building not only offers ecological and environmental advantages, but also immense skill-based advantages mainly because timber allows for component manufacturing and assembly (Green, 2019). Recent approval by the South African Bureau of Standards (SABS, 2020) of engineered wood such as cross laminated timber (CLT) has sparked interest in developing a timber research facility completely built with wood in the Pretoria central business district (CBD). The high-tech construction of such a facility would utilise manufacturing methods like the integration of building information management (BIM) programs with computer numeral control (CNC) machines to enable unskilled workers to make a building instead of constructing the building. This dissertation aims to challenge local legislation around timber construction, empower unskilled workers to make complex/ large-scale buildings and change public opinion about timber construction, as well as to create a stronger timber culture in South Africa. / Mini Dissertation (MArch (Prof))--University of Pretoria, 2020. / Architecture / MArch (Prof) / Unrestricted

Improved equations for predicting future dominant height, diameters, and number of surviving trees in a forest stand were developed for loblolly pine in the mid-Gulf region of southern United States using tree data from 115 stands across the region. The data were split into two sets and models were fitted on each data set using contemporary statistical modeling approaches in SAS® and R® software. Several models were fitted and compared. Fitted models were evaluated based on twoold cross validation techniques. The best equations had high fit indices and acceptable prediction standard errors. Model parameter estimates were significant at 5% significance level and exhibited logical model behavior. In the future, the system level performance of these equations will be evaluated after which the equations will be incorporated into the Cutover Sites Loblolly Pine growth and yield simulator developed and maintained by the Mississippi Forest and Wildlife Research Center.

Oak decline-induced mortality and failure of oak regeneration have become a concern in upland oak forests in the Missouri Ozarks. This project investigated the effects of timber harvesting on both oak regeneration and mortality of oak residuals following a suite of harvesting treatments in the Missouri Ozarks based on the sixteen-year monitoring data from the Missouri Ozark Forest Ecosystem Project (MOFEP). On dry sites by year 10, clearcutting improved the density of oak reproduction the most, and that intermediate cutting and clearcutting increased the proportion of black oak reproduction with 2% and 3%, respectively in the composition of the forests in the study area. Single-tree selection exacerbated the mortality of oak residuals, group selection and no harvesting had a similar effect on oak residuals. Intermediate cutting improved the survival of residuals the most. This project suggested well-designed silvicultural practices would likely reduce oak mortality and increase understory oak reproduction.

The aim of this study was to assess the durability of commercially available coatings on cross- laminated timber (CLT) during natural and artificial weathering and against wood decay fungus. The CLT samples coated with twelve coatings were tested based on their moisture exclusion, water repellency, volumetric swelling and anti-swelling efficiency. Among all the tested coatings, only five (A, C, F, I and J) were able to promote water repellency and limiting dimensional changes. The top five coatings were then tested on CLT blocks exposed to natural (Starkville-MS and Madison-WI) and artificial weathering conditions and brown-rot fungi (G. trabeum). Variables such as visual ratings, water uptake, color and gloss change were determined during both weathering procedures. Damage caused by Gloeophyllum trabeum on uncoated and coated CLT was analyzed based on visual appearance and weight loss. For the coatings C and F, the visual rakings and color change results indicated high consistency during outdoor exposure. The artificial weathering showed that coating C and F were the most resistant to chalking, lightness, color and gloss change. In the soil block test, coating C obtained satisfactory performance against G. trabeum with weight loss of 1.33%. Coatings F and J did not offer any protection to water penetration, which eventually contributed to fungal development. For future, new coatings specifically designed for the protection of high percentages of end-grain in CLT panels should be a target of research and development.

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