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Undergraduate students pursuing a Bachelor of Science in Forestry (BSF) at Stephen F. Austin State University (SFA) within the Arthur Temple College of Forestry and Agriculture (ATCOFA) attend an intensive 6-week hands-on instruction in applied field methods. The second week of field station is focused on land measurement activities to introduce students to practical, hands-on, and technology based ways to survey forest boundaries. On Monday of the second week students are introduced to the concepts of how to use a handheld compass to navigate from point to point, use a consumer-grade handheld Global Positioning System (GPS) unit for collecting the geographic coordinates of given locations, use a GPS unit to calculate the area of a forest opening, use a GPS unit to walk and record a forest hiking trail, and evaluate the accuracy of their GPS derived locations via a Root Mean Square Error (RMSE) analysis. RMSE analysis between a students collected geographic coordinates and the instructors collected geographic coordinates indicated that the students were sufficient in correctly recording the geographic coordinates of point, line, and polygon features identified in the field. Grades on the student submitted reports summarizing Monday's activities resulted in 33 of 56 students (59.0%) receiving a high A, 14 of 56 students (25.0%) receiving a low A, and 9 of 56 students (16.0%) receiving a high B indicating that the interactive hands-on nature of ATCOFA's field station is effective at providing students with real-world applications whereby they will be ready to make a difference the day after graduation. Interactive drone imagery and video integrated into the daily activities in the field to enhance a student's understanding of their specific objectives provided the students in the field with a bird's eye perspective of the landscape to aid their understanding and planning of the field tasks assigned. In conclusion, employers can have confidence that when hiring recent BSF graduates from ATCOFA that the students have been introduced to geospatial technologies within a proven one-on-one instruction methodology designed to increase cognitive retention and can traverse from location to location accurately and record the geographic coordinates of earth surface features correctly.

Undergraduate students pursuing a Bachelor of Science in Spatial Science degree at Stephen F. Austin State University (SFASU) receive instruction in the spatial sciences with a focus on hands-on applications. All undergraduate students take the course Introduction to Spatial Science which includes a comprehensive overview of spatial science incorporating a comparison of standard inexpensive area assessment techniques with high-end computer based area assessment methodologies. Students within this course were instructed how to assess the area of a surface feature on an aerial image with a ruler applying the transect method. Student's average Root Mean Square Error (RMSE) between a student's transect derived area and surveyed area was 0.45, 0.13, 0.07, and 0.02 acres for 5, 10, 15, and 20 transect lines, respectfully. An ANOVA analysis of area assessment and area error assessment indicated that mean area and mean absolute area error were statistically different between transect line groups. In addition, the accuracy of area measured increased significantly as the number of transect lines increased which: (1) indicates students receiving hands-on instruction in estimating area using the transect method can record accurate area measurements after only a limited 2 hour introduction; (2) reveals the accuracy of the transect method is not user dependent; (3) shows area accuracy increases as the number of transects increases; and, (4) validates the interactive hands-on instruction methodology employed at SFASU.

Tree height is a critical variable of forest inventory assessments, and estimating the height of trees has been a component of forest inventory assessments for decades. The actual tree height of 60 open-grown baldcypress (Taxodium distichum) trees measured with a telescopic height pole were compared to Pictometry hyperspatial 4-in. multispectral imagery estimated tree height on the campus of Stephen F. Austin State University, Nacogdoches, Texas. Linear correlation coefficients (r) between actual tree height and Pictometry-estimated tree height for all 60 trees and the shortest 30 and tallest 30 trees were >0.997 for all r values. Pictometry-estimated tree height was within, on average, 1.77, 2.15, and 1.40% of actual tree height for all 60 trees, the shortest 30 trees, and the tallest 30 trees, respectively. All three paired t-tests, for all 60 trees, the shortest 30 trees, and the tallest 30 trees, resulted in a P value ≥0.08, indicating that there was no statistical significance between actual and estimated tree height at a 95% confidence level. Pictometry-estimated tree height can be used in lieu of field-based tree height estimation for open-grown urban forests. [ABSTRACT FROM AUTHOR]

A new distance-based estimator for forest regeneration assessment, the mean distance method, was developed by combining ideas and techniques from the wandering quarter method, T-square sampling and the random pairs method. The performance of the mean distance method was compared to conventional 4.05 square meter plot sampling through simulation analysis on 405 square meter blocks of a field surveyed clumped distribution and a computer generated random distribution at different levels of density of 100, 50 and 25%. The mean distance method accurately estimated density on the random populations but the mean distance method estimates were more variable than those of 4.05 square meter plot sampling. The mean distance method overestimated actual density and was less precise than plot sampling when both methods were tested on the clumped populations. The optimum sample sizes needed for the mean distance method to achieve the same precision as 4.05 square meter plot sampling at all three density levels, for both the random and clumped spatial distributions, were at least 10 times larger than the sample size used for 4.05 square meter plot sampling. [ABSTRACT FROM AUTHOR]

Land cover maps of forests within an urban and rural environment derived from high spatial resolution multispectral data (QuickBird) and medium spatial resolution multispectral data (Landsat ETM+ and SPOT 4) were compared to ascertain whether increased spatial resolution increases map accuracy of forests and whether map accuracy varies across land cover classification schemes. It is commonly assumed that Increased spatial resolution would probably increase land cover map accuracy regardless of land cover classification methodology. This study assessed whether that assumption is correct within a rural and an urban environment. Map accuracy for modified National Land Cover Data (NLCD) 2001 Level II, Level I, and Unique (a modified NLCD 2001 Level II and Level I combination) shows that 30-m Landsat ETM + data hod the highest overall map accuracy for rural, urban, and combined rural/urban land cover maps. Analysis of user's and producer's accuracies shows that Landsat ETM+ data had higher levels of producer's accuracy of >90.0% for the coniferous cover type for modified NLCD 2001 Level II and Unique, excluding one instance for which SPOT 4 had a user's accuracy of 98.5% for the rural coniferous cover type. Modified NLCD 2001 Level I Landsat ETM+ data had user's and producer's accuracies for a homogeneous forest cover type of 98.4 and 90.6%, respectively. Landsat ETM+ data also outperformed SPOT 4 and QuickBird within an urban environment, creating the only map products with forest cover type user's and producer's accuracies of >90.0%. [ABSTRACT FROM AUTHOR]

Field foresters have long required a method of accurate measurement of perimeter and area during forest management activities. Perimeter and area assessments that can be derived from individual waypoints collected via global positioning system (GPS) units can be an expensive endeavor. A question of concern for practicing foresters is as the cost of GPS units increase does the accuracy of waypoints and any derived perimeter and area assessments also increase? This research evaluated whether the dynamic collection of waypoints using consumer-grade GPS units ranging from $50 to $700 provide a sufficient level of Ml accuracy for the calculation of perimeter and area under three types of canopy cover: a newly established 3-year-old pine plantation, a 13-year-old pine plantation nearing first thinning, and a 40-year-old mixed pine/hardwood stand. Perimeter and area accuracy was not related to cost indicating that inexpensive GPS units provide an accurate waypoint location when used to derive perimeter and area measurements. When compared to a professional survey of each cover |i type, the average perimeter root mean square error (RMSE) ranged from 18.72 ft (0.41% of total perimeter) in the 40-year-old mixed pine/hardwood stand to 108.50 ft (2.43% of total perimeter) in the 13-year-old pine plantation. The average area RMSE observed ranged from 0.07 acres (0.22% of total acreage) in the 3-year-old plantation to 1.32 acres (4.67% of total acreage) in the 13-year-old pine plantation. For many forestry applications needing a perimeter and acreage assessment, these levels of accuracy should be more than sufficient. [ABSTRACT FROM AUTHOR]