This study has significantly broadened and deepened the understanding of ecological aspects related to the spread and reproduction of Diplodia pinea as an endophyte, latent pathogen and causal agent of serious disease problems in plantations of Pinus spp. Analyses of genetic diversity in populations using microsatellite data has revealed very high levels of genetic diversity of populations of the pathogen at different spatial levels, ranging from within a single asymptomatic tree to within and between plantations over large geographic areas and in different countries where the fungus has been introduced. Analysis of the structure of the distribution of genotypes and the association of alleles within populations, suggest that sexual recombination is occurring in most environments in the Southern Hemisphere D. pinea populations. This indicates the presence of a cryptic sexual state in this fungus. The genetic diversity was structured and differentiated for regions separated by as little as 65 km to a country and continental scale. The diversity and likely sexual reproduction of D. pinea must complicate control strategies such as selection and breeding for resistance. It is thus essential to strengthen quarantine services aimed at minimizing the risk of introducing additional genotypes of D. pinea. In this regard, understanding the infection and spread between regions is essential. Results of this study demonstrate that this fungus infects seeds, but only at low levels, and is not transmitted vertically via seeds to seedlings. Diplodia pinea was also not isolated from seedlings in three commercial nurseries and open fields in South Africa. These results provide strong evidence that neither seeds nor seedlings are the primary sources of inoculum, but that the pathogen is mainly transmitted horizontally from mature trees and debris left in plantations. Finally extensive sampling conducted as part of this study led to the discovery of the sibling species, D. scrobiculata in South Africa and outside the Northern Hemisphere for the first time. / Thesis (PhD)--University of Pretoria, 2011. / Genetics / Unrestricted

A shipment of 5,591 board feet of dense select structural southern pine, graded and inspected to conform to standard grading rules for southern pine lumber, was carefully investigated in order to determine (1) whether the lumber is within grade limitations, (2) what are the variations in and ranges of its physical and mechanical properties, and (3) whether it fulfills anticipations of design specifications. Within its limitations, the study indicates that the investigated lumber fulfills the expectations of the National Design Specification despite the fact that some of the planks are found below grade according to the standard grading rules. Hence, those recommendations of the National Design Specification subjected to investigation are substantiated by laboratory test data on a commercially stress-graded shipment of southern pine lumber. / Master of Science

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Plant fossils from the Citronelle Formation provide a rare window into the Pliocene flora and climate of the northeastern Gulf of Mexico Coastal Plain. Many of the taxa recovered to date inhabit the region today. However, analysis of Pinus pollen grains and fascicles indicates that the dominant pines were members of Pinus subgenus Strobus (i.e., "white pines"). The fascicles have a small, bulbous base lacking a sheath, and bear four or five long, slender needles. These features are typical of white pines. Although macrofossils are rare, 77 to 100% of the dispersed Pinus pollen grains from five localities have sacci continuous with the corpus and verrucae on the cappula, which are characteristics of white pines. This is remarkable, as the northeastern Gulf of Mexico Coastal Plain today is devoid of white pines, and is instead considered a center of diversity for Pinus subgenus Pinus section Pinus subsection Australes. Today, Pinus strobus is the only white pine in the eastern North America and its southernmost distribution only extends into the mountains of Georgia, about 600 km north of the fossil sites. The historical biogeographic relationships of P. strobus to other North American forms are unclear. For example, its close relative, Pinus chiapensis, is present in northeastern Mexico and Central America. The current disjunction between P. strobus and P. chiapensis is 2400 km and includes an arid barrier to dispersal. P. chiapensis is also associated with several other species showing a similar biogeographic pattern. The fossils described here indicate that white pines were more widespread in North America in the recent geological past than previously thought, and imply possible connections between disjunct species that would not be suspected if only current species' ranges and ecological tolerances were considered.

"The volume contains a wealth of ceramic type-variety descriptive and interpretive data, as well as an excellent descriptive treatment of the ethnobotanical remains, and solid coverage of the lithic, faunal, and other classes of artifactual materials. The quality of illustrative material is excellent, including outstanding field and artifact photography and carefully prepared charts and line drawings."—American Antiquity

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My goal is to learn the history of Hilton Head Island and logically reason out the way it grew, marking Sea Pine’s design influence over time and place. This paper is meant to be a piece of nature and history writing, which has implications for the study of environmental economics and real-estate design practices, but is not strictly about either. The thrust of this piece is the mapping of developmental philosophies and their reflection in the land. This topic interests me because at its core, it looks at how decisions are made, and the trade offs that influence them. The paper is also about the formation of ideas that explore sustainable forms of human-environment interaction, but which do not give up the high quality of life that modern man has come to expect. Environmental issues will continue to influence social, economic and political thought as we move towards midcentury. Sea Pines champions a blending of man and nature that may be able to provide alternative and more efficient solutions to the problems that our society faces.