Forest Sciences Commons^™

Overstory Tree Mortality In The Ponderosa Pine And Spruce-Fir Ecosystems, Following A Drought In Northern New Mexico, Brian P. Oswald, Sean Dugan, Randy Balice, Daniel Unger

Faculty Publications

Drought-caused tree dieback is an issue around the world as climates change and many areas become dryer and hotter. A drought from 1998-2004 resulted in a significant tree dieback event in many of the wooded areas in portions of the Jemez Mountains and the adjacent Pajarito Plateau in northern New Mexico. The objectives of this study were to evaluate and quantify the differences in tree mortality before and after a recent drought in the ponderosa pine and spruce-fir ecosystems, and to assess the effect of mechanical thinning on ponderosa pine mortality. Significant increases in mortality were observed in the unthinned …

Comparing Remotely Sensed Pictometry® Web Based Slope Distance Estimates With In Situ Total Station And Tape Slope Distance Estimates, David Kulhavy, Daniel Unger, Yanli Zhang, Phillip Bedford, I-Kuai Hung

Faculty Publications

Slope distance was measured between the top of 30 light poles and their respective ground level coordinate identified within a central parking lot on the campus of Stephen F. Austin State University, Nacogdoches, Texas. Slope distance measured using Pictometry^® hyperspatial 4-inch (10.2 centimeters) multispectral imagery within a web based interface was compared to in situ total station and tape measured slope distance. The range for mean slope distance for Pictometry^®, total station, and tape measured slope distance was 0.05 meters. Mean slope distance was 15.36 meters, 15.37 meters, and 15.41 meters for Pictometry^®, total station, …

Incorporating Applied Undergraduate Research In Senior To Graduate Level Remote Sensing Courses, Richard Henley, Daniel Unger, David Kulhavy, I-Kuai Hung

Faculty Publications

An Arthur Temple College of Forestry and Agriculture (ATCOFA) senior spatial science undergraduate student engaged in a multi-course undergraduate research project to expand his expertise in remote sensing and assess the applied instruction methodology employed within ATCOFA. The project consisted of performing a change detection land-use/land-cover classification for Nacogdoches and Angelina counties in Texas using satellite imagery. The dates for the imagery were spaced approximately ten years apart and consisted of four different acquisitions between 1984 and 2013. The classification procedure followed and expanded upon a series of concrete theoretical remote sensing principles, transforming the four remotely sensed raster images …

Effects Of First Thinning On Growth Of Loblolly Pine Plantations In The West Coastal Plain, Dean W. Coble, Jason Grogan

Faculty Publications

The purpose of this research is to analyze thinning response in basal area and height growth of residual loblolly pine trees growing in plantations located in the West Gulf Coastal Plain. Thinning is a well-known silvicultural practice that increases the growing space available to desirable trees by removing competing trees.

Use Of A Portable Sawmill For Forestry Instruction, Matthew Mcbroom, David Kulhavy, Jeremy Stovall, Ryan P. Grisham

Faculty Publications

The Arthur Temple College of Forestry and Agriculture at Stephen F. Austin State University in Nacogdoches, TX, has implemented an experiential learning exercise to improve student learning related to the forest products industry. During the week-long sophomore- or junior-level course Harvesting and Processing, forestry students tour multiple wood products facilities such as sawmills. These mills use complex technologies to maximize the lumber produced from each log, and students were having difficulty understanding the underlying concepts. As part of this course beginning in 2012, students began working in teams to estimate the lumber that will be recovered from a log and …

Evaluating Interactive Transect Area Assessments Hands-On Instruction For Natural Resource Undergraduate Students, Daniel Unger, Sarah Schwab, Ryan Jacques, Yanli Zhang, I-Kuai Hung, David L. Kulhavy

Faculty Publications

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 …

Spatial Distribution Of Earthworms In An East Texas Forest Ecosystem, Melissa A. Bozarth, Kenneth W. Farrish, George A. Damoff, James Van Kley, J. Leon Young

Faculty Publications

Earthworms were collected and identified in different ecological habitats of the Stephen F. Austin Experimental Forest (SFAEF) in the Piney Woods Ecoregion (PWE) of Texas. Earthworm spatial distribution data were collected over four distinct ecological habitats with a range of soil conditions and vegetative cover. A total of 128 sampling plots were surveyed in two different, broadly defined locations (mesic slope = 68 plots, dry-mesic upland = 60 plots). Using multivariate classification/ordination (TWINSPAN) and detrended correspondence analysis (DCA) of overstory vegetation data, these two locations were further divided into four distinct habitats: dry-mesic mixed upland, transitional zone, mesic slope and …

Quantifying Land Cover Change Due To Petroleum Exploration And Production In The Haynesville Shale Region Using Remote Sensing, Daniel Unger, I-Kuai Hung, Kenneth W. Farrish, Darinda Dans

Faculty Publications

The Haynesville Shale lies under areas of Louisiana and Texas and is one of the largest gas plays in the U.S. Encompassing approximately 2.9 million ha, this area has been subject to intensive exploration for oil and gas, while over 90% of it has traditionally been used for forestry and agriculture. In order to detect the landscape change in the past few decades, Landsat Thematic Mapper (TM) imagery for six years (1984, 1989, 1994, 2000, 2006, and 2011) was acquired. Unsupervised classifications were performed to classify each image into four cover types: agriculture, forest, well pad, and other. Change detection …

Resin Production In Natural And Artificial Red-Cockaded Woodpecker Cavity Trees, David Kulhavy, Kimberly B. Rozelle, William G. Ross, Daniel Unger, Richard N. Conner

Faculty Publications

Resin flow was measured in red-cockaded woodpecker (Picoides borealis Vieillot) clusters in longleaf pine (Pinus palustris Mill.) in the southern region of the Angelina National Forest, Texas. Resin flow (ml) at 1.4 m height over 24 hrs was measured from one 2.5 cm punch through the phloem between 0700 and 1000 hrs from March 1999 to September 2000, for a total of 9 measurements per tree. Resin was sampled in naturally active cavity trees, artificial (insert) active, natural inactive, artificial inactive and control pines (84 sample trees). Resin flow pattern was significantly different during the year, but not significantly different …

Effects Of Competing Vegetation On Growth Of Loblolly Pine Plantations In The West Gulf Coastal Plain, Dean W. Coble

Faculty Publications

No abstract provided.

Integrating Hands-On Undergraduate Research In An Applied Spatial Science Senior Level Capstone Course, David Kulhavy, Daniel Unger, I-Kuai Hung, David Douglass

Faculty Publications

A senior within a spatial science Ecological Planning capstone course designed an undergraduate research project to increase his spatial science expertise and to assess the hands-on instruction methodology employed within the Bachelor of Science in Spatial Science program at Stephen F Austin State University. The height of 30 building features estimated remotely with LiDAR data, within the Pictometry remotely sensed web-based interface, and in situ with a laser rangefinder were compared to actual building feature height measurements. A comparison of estimated height with actual height indicated that all three estimation techniques tested were unbiased estimators of height. An ANOVA, conducted …

Urban Tree Height Assessment Using Pictometry Hyperspatial 4-Inch Multispectral Imagery, Daniel Unger, David Kulhavy, Jeffrey M. Williams, David Creech, I-Kuai Hung

Faculty Publications

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 [1]0.997 for all r values. Pictometry estimated tree …

If It Pays, It Stays - Rewarding Private Forest Landowners, Steven H. Bullard

Faculty Publications

Article discusses monetizing the "ecosystem services" provided by private landowner forests. It discusses the potential of "workable vehicles" for rewarding landowners of private forest landowners for the many benefits their forests provide.

Stereo Photo Series For Estimating Natural Fuels In The Netherlands Volume 3: Veen, Brian P. Oswald

Faculty Publications

The photo series is a collection of photos and associated field data representing a region of The Netherlands. Volume 3 includes peatland vegetation types located in Northumberland National Park in England. These sites were used to represent those found in The Netherlands since peatlands in the UK are larger and thereby better for the field research. For each vegetation type, sites were sampled with varying fuel loads. The description of the sites consists of a wide-angle site photo, supplemented with field data on the various fuel loads and vegetative layers. The photo series is an important ecological tool to assess …

Loblolly Pine Growth Patterns On Reclaimed Mineland: Allometry, Biomass, And Volume, Jeremy Priest, Jeremy Stovall, Dean Coble, Brian Oswald, Hans Williams

Faculty Publications

Surface lignite coal mines in east Texas are commonly reforested using loblolly pine (Pinus taeda L.) following mining and reclamation activities. Due to the nature of such an extreme disturbance, altered growth patterns, growth rates, and productivity could be expected. We destructively sampled above- and belowground tissue to develop prediction equations specific to these sites. These prediction equations differed statistically from those found in the literature regarding unmined land. At the stand level, biomass and volume productivity appeared similar with young stands on reclaimed mineland performing slightly poorer than similarly managed unmined sites. Allometric partitioning of above- and belowground biomass …

Decomposition Of Three Common Moist-Soil Managed Wetland Plant Species, Daniel P. Collins, Warren C. Conway, Corey D. Mason, Jeffrey W. Gunnels

Faculty Publications

Moist-soil wetland management is used to precisely control delivery, duration, and timing of water addition to, and removal from, managed wetlands with targeted responses including germination and growth of desirable moist-soil plant species. Similarly, water delivery and removal drives decomposition of moist-soil plants as well as nutrient cycling within these systems, which is a key driver of productivity in such managed wetlands. Through deployment of litter bags, we examined rate of mass loss and decay coefficients of three locally abundant moist-soil annual species that are potentially valuable wintering-waterfowl food sources (nodding smartweed Persicaria lapathifolia, red-rooted flatnut sedge Cyperus erythrorhizos …

Waas, Glonass, And Gps Accuracy, Yanli Zhang, Daniel Unger, I-Kuai Hung, David Kulhavy

Faculty Publications

No abstract provided.

Evaluating Gps Effectiveness For Natural Resource Professionals: Integrating Undergraduate Students In The Decision-Making Process, Daniel Unger, I-Kuai Hung, Yanli Zhang, David Kulhavy

Faculty Publications

Undergraduate students pursuing a Bachelor of Science in Forestry (BSF) degree at Stephen F. Austin State University (SFA) attend an intensive 6-week residential hands-on instruction in applied field methods. For students pursuing the BSF degree knowing the exact location of a forestland is crucial to the understanding and proper management of any related natural resource. The intensive 6-week instruction includes teaching how to use the Global Positioning System (GPS) to accurately record the spatial location of an earth’s surface feature. After receiving hands-on instructions during the summer of 2014, students were taken to the field to collect real-world locations. Students …

Bullish On Forestry Careers, Steven H. Bullard, Thomas J. Straka

Faculty Publications

During the next decade, baby boomer-aged foresters, those born from 1946 to 1964, will be retiring in large numbers. This retirement trend is true for all sectors of forestry employment, from state and federal agencies to private firms and industries.

Forestry employers in both public and private sectors are clamoring for more graduates, as well as for more diverse graduates, from forestry degree programs. With looming retirements and industry growth, employers can project the number of positions opening, and they are aware that U.S. forestry schools are not producing sufficient graduates to fill the positions.

A Test Of The Mean Distance Method For Forest Regeneration Assessment, Daniel Unger, Jeremy P. Stovall, Brian P. Oswald, David Kulhavy, I-Kuai Hung

Faculty Publications

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 …

Accuracy Assessment Of Land Cover Maps Of Forests Within An Urban And Rural Environment, Daniel Unger, I-Kuai Hung, David L. Kulhavy

Faculty Publications

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 SPOJ 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 …

Quantifying Natural Resources Using Field-Based Instruction And Hands-On Applications, Daniel Unger, David Kulhavy, I-Kuai Hung, Yanli Zhang

Faculty Publications

Undergraduate students pursuing a Bachelor of Science in Forestry (BSF) degree at Stephen F. Austin State University (SFA) attend an intensive 6-week residential hands-on instruction in applied field methods. For students pursuing the BSF degree knowing the exact location, length, or area of a forestland is crucial to the understanding and proper management of any related natural resource. The intensive 6-week instruction includes teaching how to use the Global Positioning System (GPS) to accurately record the true spatial location of an earth’s surface feature. After receiving hands-on instructions during the summer of 2013, students were taken to the field to …

Using Google Earth For Forest Management, Yanli Zhang, Jeremy P. Stovall

Faculty Publications

No abstract provided.

Using Infrared-Triggered Cameras To Monitor Activity Of Forest Carnivores, Matthew E. Symmank, Christopher E. Comer, James C. Kroll

Faculty Publications

The activity patterns of 4 forest predator species were monitored, using infrared-triggered cameras, within a 1318-ha study area in East Texas. We recorded 161 photographic capture events in 1925 trap-nights over 17 weeks. Photographic capture events included 18 Lynx rufus (Bobcat), 109 Procyon lotor (Raccoon), 21 Didelphis virginiana (Virginia Opossum), and 13 Canis latrans (Coyote). We developed an easily replicated method of measuring time on a percent scale to compare activity data over several months, accounting for changes in sunrise and sunset times. Bobcat activity was 38.9% crepuscular and 22.1% diurnal. The activity of the other 3 species was mostly …

University-Based Forestry Research And "The Little Red Hen", Steven H. Bullard

Faculty Publications

Universities have three basic mission areas: service, teaching, and research. Through the service mission, many forest landowners participate in forestry extension programs and use university-based out reach materials and resources. Many forest landowners also recognize the teaching mission of universities by interacting regularly with forestry professionals who were trained through academic programs accredited by the Society of American Foresters. These two mission areas, service and teaching, have been and continue to be relevant to millions of forest landowners across the nation.

But what about university-based forestry research? As a forestry dean and as current president of the National Association of …

Measuring Tree Height Using Pictometry Hyperspatial Imagery, Daniel Unger, David Kulhavy, Matthew A. Wade, I-Kuai Hung

Faculty Publications

Trees within Nacogdoches, Texas were measured for height using Pictometry hyperspatial imagery at 4 inch spatial resolution. Trees measured included baldcypress located on LaNana Creek as part of a hybrid analysis study. Baldcypress, Taxodiumdistichum, was planted along La Nana Creek, Nacogdoches, Texas, for erosion control and as a test bank for growth of the species genotypes. Each tree was located with GPS and entered into the GIS data base in the Arthur Temple College of Forestry and Agriculture, Stephen F. Austin State University. Actual tree height, measured using a height pole in 0.1 inch increments, was compared to …

Instream Woody Debris And Riparian Forest Characteristics In The Sabine River, Texas, Matthew W. Mcbroom, Michael Ringer, Yanli Zhang

Faculty Publications

We examined instream large woody debris (LWD) dynamics on the Sabine River, TX. All wood >10 cm in diameter and >2 m long was measured on four river meanders (meander wavelengths) below the dam on Toledo Bend Reservoir. We determined LWD species, degree of decay, bank orientation, jam association, and stage contact. We also measured riparian vegetation characteristics on each meander. LWD volumes were significantly greater at the site immediately below Toledo Bend Dam, due to the relatively steeper channel gradient and higher rates of channel erosion. Based on mass balance estimates, between 11 and 21% of total annual recruitment …

Producing “Society-Ready” Foresters: A Research-Based Process To Revise The Bachelor Of Science In Forestry Curriculum At Stephen F. Austin State University, Steven H. Bullard, Pat Stephens Williams, Theresa Coble, Dean W. Coble, Ray Darville, Laurie Rogers

Faculty Publications

“Society-ready” foresters are capable of dealing effectively with the complex economic, ecological, and social issues involving forestry in the 21st century. To assess the knowledge areas, skill sets, abilities, and behaviors needed by society-ready, entry-level foresters today, we surveyed 800 forestry employers and forestry alumni from Stephen F. Austin State University (SFASU), and we also conducted focus group sessions with a total of 58 forestry employers. Important areas of knowledge on emerging issues for society-ready Bachelor of Science in Forestry (BSF) graduates included climate change, water availability and quality, and dealing with invasive plants, pathogens, and insects. However, the skill …

Artificial Nests Identify Possible Nest Predators Of Eastern Wild Turkeys (Abstract Only), Warren C. Conway, Christopher E. Comer

Faculty Publications

No abstract provided.

Roosts Of Rafinesque’S Big-Eared Bats And Southeastern Myotis In East Texas (Abstract), Leigh A. Struemke, Christopher E. Comer, Warren C. Conway

Faculty Publications

No abstract provided.