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Ian-Huei Yau, Joan R. Davenport, and Michelle M. Moyer

layers. Spatial data sources are summarized in Table 1 . Geographic information system software packages used were ArcGIS (versions 9.3.1 and 10.0; Esri, Redlands, CA). Tabular data were spatially represented using geographic coordinates provided by

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Arnold W. Schumann

orchard ( Fig. 1 ) calculated from remotely sensed color-infrared aerial photography and the normalized difference vegetation index (NDVI). Dark green is most productive; dark red is least productive. Geographic information systems and global positioning

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Justin A. Porter, David Berle, and Hazel Y. Wetzstein

Botanical Garden of Georgia, Athens, GA Clark, J.D. Dunn, J.E. Smith, K.G. 1993 A multivariate model of female black bear habitat use for a geographic information system J. Wildl. Mgt. 57 519 526 Coates, D.J. Sampson, J.F. Yates, C.J. 2007 Plant mating

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Ghazal Tarar, Coleman L. Etheredge, Amy McFarland, Amy Snelgrove, Tina M. Waliczek, and Jayne M. Zajicek

eighties. Wiley, Chichester, UK Snelgrove, A.G. Michael, J.H. Waliczek, T.M. Zajicek, J.M. 2004 Urban greening and criminal behavior: A geographic information system perspective HortTechnology 14 48 51 Spierings, E.L. Ranke, A.H. Honkoop, P.C. 2001

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Timothy L. Righetti and Michael D. Halbleib

Agriculture is changing. State-of-the-art computer systems that use GPS (global positioning systems) data, GIS (geographic information systems) software, remotely sensed images, automated sampling, and information analysis systems are transforming growers' ability to produce their crops. Currently, the farm service and agricultural sales industry, rather than the grower direct most information technology applications. Precision agriculture must become an information-driven and grower-driven process. Data evaluation has to be made simpler, less time consuming, and inexpensive. The purpose of this paper is to outline potential strategies and demonstrate how information can be processed and evaluated with readily available and inexpensive analytical tools.

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I.H. Perry, J.M. Zajicek, and S.L. Hatch

Understanding the effect of catastrophic disturbances on natural communities is necessary and vital to planning and executing development and to reclamation and restoration projects. Two nearby sites one catastrophically disturbed by flooding and one undisturbed area were compared. Field vegetation analysis three years after the flood in the disturbed area showed changes in the community structure along the stream, no overstory and a majority of obligate emergent wetland vegetation. In the undisturbed site, community structure along the stream is uniform; the overstory is well-developed, and herbaceous plants are predominantly facultative wetland but with few emergents. The field water quality analysis of temperature, pH, dissolved oxygen and specific conductivity are compared in the areas. GIS (Geographic Information System) analysis used the USGS 1:24,000 maps of the area and SCS county soil survey maps to analyze erosion risk, soil types, topography and vegetation potential in the 200 km2 Miller Springs Natural Area and the immediately surrounding 5 10 km2 watershed.

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D.L. Creech and D. McDonald

Texas is botanically diverse with approximately 5500 native plants identified: east Texas contains about 40% of the total. While most species are stable, many are classified as rare, threatened, vulnerable, or endangered. Databases for east Texas plant communities and vegetative analyses are numerous. However, they are not yet integrated into easy-to-sort-and-query computer files. Computer-Assisted Drafting (CAD) and Geographic Information Systems (GIS) technology offers powerful applications to the storage, management, and spatial analysis of species inventories, plant community dynamics, and long-term habitat monitoring. At SFASU, the College of Forestry's GIS Center is being utilized to develop comprehensive east Texas resource inventories on a ten-station HP Apollo/ArcInfo platform. In the horticulture program, a twenty-station PC/AutoCad teaching laboratory is being used to create layered maps of the SFASU Arboretum, the on-campus landscape and off-campus plant communities. The integration of CAD and GIS projects through a DXF format takes advantage of the attributes of both technologies.

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Karen A. Williams

The Plant Exploration Program was established by USDA in 1898, several decades before the emergence of the US National Plant Germplasm System (NPGS), and continues to support international and domestic plant explorations for germplasm acquisition. These explorations are designed to fill collection gaps identified by the crop curators of the NPGS and the 40 Crop Germplasm Committees that counsel the NPGS. About 15 explorations are conducted annually under the auspices of this program. Although plant explorations to remote areas are often still the only means of acquiring unique new germplasm, the focus and methods applied by modern plant explorers have changed significantly in recent years in response to evolving germplasm needs and the new opportunities presented by recent technological advances. Modern explorations are characterized by the targeting of specific taxa and traits. New exploration techniques and tools, including geographic information systems and improved methods of data collection, are being applied to locate, document, and assess plant genetic diversity. During the past decade, legal obstacles faced by the Program have increased due to restrictive laws implemented in germplasm donor countries that exercise their national sovereignty over genetic resources, replacing the free and open access to genetic resources that prevailed before the ratification of the Convention on Biological Diversity in 1993. The NPGS has responded to these regulatory challenges with a flexible approach that includes nonmonetary benefit sharing and increased partnerships with host countries.

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D. Creech, D. McDonald, D. Kulhavy, and P. Blackwell

This paper outlines the history of the SFA Arboretum's effort to establish a campus-as-arboretum at the university. In 1996, the participants created a robust Geographic Information System (GIS) for the campus forest based primarily on a 1993-95 campus mapping and tree inventory project in the 144-acre main core of the campus (Wilson to North St.; College to Starr). The project served as the MS thesis of Susan Perkins. In brief, the campus model reveals a pine-dominated Type 2 forest (one rapidly approaching maturity), difficult campus hydrology issues, and a landscape low on diversity with 68 species represented. In 1996, the Arboretum's AutoCAD® map and Excel® tree data files were integrated into the College of Forestry Unix-based ArcInfo® platform. This now provides full GIS capabilities for landscape planners. The resultant maps based on user queries reveal a robust vegetation analysis and management tool. In 1997, the SFA administration, Physical Plant, Grounds, College of Forestry, and SFA Arboretum initiated a “campus beautification” funding campaign. The SFA Arboretum will play a key role in building unique, documented, and mapped woody ornamental collections for the campus. This provides a unique opportunity in the South for long-term Zone 8 woody plant evaluation in a high-visibility and “perpetual” landscape.

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N.S. Lang, L. Mills, R.L. Wample, J. Silbernagel, E.M. Perry, and R. Smithyman

Research suggests that blackleaf (a leaf disorder in grape, Vitis labrusca L.) is induced by high levels of ultra violet (UV) radiation and overall light intensity, resulting in color changes (purple-brown-black) for sun-exposed leaves of the outer canopy, and a corresponding >50% reduction in photosynthesis. Metabolic indicators (photosynthesis and leaf water potential), percent blackleaf expression, and full spectrum leaf reflectance were mapped within vineyards using global positioning system (GPS) and digital remotely-sensed images. Each image and data record was stored as an attribute associated with a specific vine location within a geographical information system (GIS). Spatial maps were created from the GIS coverages to graphically present the progression of blackleaf across vineyards throughout the season. Analysis included summary statistics such as minimum, maximum, and variation of green reflectance, within a vineyard by image capture date. Additionally, geostatistics were used to model the degree of similarity between blackleaf values as a function of their spatial location. Remote-image analysis indicated a decrease in percent greenness of about 45% between July and August, which was related to a decrease in photosynthesis and an increase in blackleaf symptom expression within the canopy. Examination of full spectral leaf reflectance indicated differences at specific wavelengths for grape leaves exposed to UV or water-deficit stress. This work suggests that remote-image and leaf spectral reflectance analysis may be a strong tool for monitoring changes in metabolism associated with plant stress.