@article{sanders_jones_austin_roberson_richardson_everman_2021, title={Remote Sensing for Palmer Amaranth (Amaranthus palmeri S. Wats.) Detection in Soybean (Glycine max (L.) Merr.)}, volume={11}, ISSN={["2073-4395"]}, DOI={10.3390/agronomy11101909}, abstractNote={Field studies were conducted in 2016 and 2017 to determine if multispectral imagery collected from an unmanned aerial vehicle (UAV) equipped with a five-band sensor could successfully identify Palmer amaranth (Amaranthus palmeri) infestations of various densities growing among soybeans (Glycine max [L.] Merr.). The multispectral sensor captures imagery from five wavebands: 475 (blue), 560 (green), 668 (red), 840 (near infrared [NIR]), and 717 nm (red-edge). Image analysis was performed to examine the spectral properties of discrete Palmer amaranth and soybean plants at various weed densities using these wavebands. Additionally, imagery was subjected to supervised classification to evaluate the usefulness of classification as a tool to differentiate the two species in a field setting. Date was a significant factor influencing the spectral reflectance values of the Palmer amaranth densities. The effects of altitude on reflectance were less clear and were dependent on band and density being evaluated. The near infrared (NIR) waveband offered the best resolution in separating Palmer amaranth densities. Spectral separability in the other wavebands was less defined, although low weed densities were consistently able to be discriminated from high densities. Palmer amaranth and soybean were found to be spectrally distinct regardless of imaging date, weed density, or waveband. Soybean exhibited overall lower reflectance intensity than Palmer amaranth across all wavebands. The reflectance of both species within blue, green, red, and red-edge wavebands declined as the season progressed, while reflectance in NIR increased. Near infrared and red-edge wavebands were shown to be the most useful for species discrimination and maintained their utility at most weed densities. Palmer amaranth weed densities were found to be spectrally distinct from one another in all wavebands, with greatest distinction when using the red, NIR and red-edge wavebands. Supervised classification in a two-class system was consistently able to discriminate between Palmer amaranth and soybean with at least 80% overall accuracy. The incorporation of a weed density component into these classifications introduced an error of 65% or greater into these classifications. Reducing the number of classes in a supervised classification system could improve the accuracy of discriminating between Palmer amaranth and soybean.}, number={10}, journal={AGRONOMY-BASEL}, author={Sanders, John T. and Jones, Eric A. L. and Austin, Robert and Roberson, Gary T. and Richardson, Robert J. and Everman, Wesley J.}, year={2021}, month={Oct} }
 @article{jordan_hare_roberson_ward_shew_brandenburg_anco_thomas_balota_mehl_et al._2019, title={Survey of Practices by Growers in the Virginia-Carolina Region Regarding Digging and Harvesting Peanut}, volume={5}, ISSN={["2374-3832"]}, DOI={10.2134/cftm2019.07.0057}, abstractNote={Core Ideas Harvesting peanut requires approximately twice as much time to complete as the time required for digging peanut. Fifty-six percent of growers predicted when optimum yield would occur based on the sample provided within the recommended timeframe. Reported yield was positively correlated with the use of prohexadione calcium.}, number={1}, journal={CROP FORAGE & TURFGRASS MANAGEMENT}, author={Jordan, David L. and Hare, Andrew T. and Roberson, Gary T. and Ward, Jason and Shew, Barbara B. and Brandenburg, Rick L. and Anco, Dan and Thomas, James and Balota, Maria and Mehl, Hillary and et al.}, year={2019}, month={Nov} }
 @article{sanders_everman_austin_roberson_richardson_2019, title={Weed species differentiation using spectral reflectance and image classification}, volume={11007}, ISSN={["1996-756X"]}, url={http://dx.doi.org/10.1117/12.2519306}, DOI={10.1117/12.2519306}, abstractNote={Advancements in efficient unmanned aerial platforms and affordable sensors has led to renewed interest in remote sensing by agricultural producers and land managers for use as an efficient and convenient method of evaluating crop status and pest issues in their fields. For remote sensing to be employed as a viable and widespread tool for weed management, the accurate detection of distinct weed species must be possible through the use of analytical procedures on the resultant imagery. Additionally, the remote sensing platform and subsequent analysis must be capable of identifying these species across a wide range of heights. In 2017, a field study was performed to identify any weed height thresholds on the accurate detection and subsequent classification of three common broadleaf weed species in the southeastern United States: Palmer amaranth (Amaranthus palmeri), common ragweed (Ambrosia artemisiifolia) and sicklepod Senna obtusifolia) as well as the classification accuracy of image classifications performed on the species scale. Pots of the three species at heights of 5, 10, 15, and 30 cm were randomly arranged in a grid and 5-band multispectral imagery was collected at 15 m. Image analysis was used to identify the spectral reflectance behavior of the weed species and height combinations and to evaluate the accuracy of species based supervised classifications involving the three species. Supervised classification was able to discriminate between the three weed species with between 24-100% accuracy depending on height and species. Palmer amaranth classification accuracy was consistently 100%. Increased height of sicklepod and common ragweed plants did not reliably confer improved accuracy but the species were correctly identified with at least 24% and 60% accuracy, respectively.}, journal={ADVANCED ENVIRONMENTAL, CHEMICAL, AND BIOLOGICAL SENSING TECHNOLOGIES XV}, author={Sanders, J. T. and Everman, W. J. and Austin, R. and Roberson, G. T. and Richardson, R. J.}, year={2019} }
 @article{jordan_hare_roberson_shew_brandenburg_anco_balota_mehl_taylor_2018, title={Summary of Variables Associated with Application of Plant Protection Products in Peanut}, volume={4}, ISSN={["2374-3832"]}, DOI={10.2134/cftm2018.05.0034}, abstractNote={Core Ideas
Peanut acreage was positively correlated with tank size, boom width, and ground speed.
Peanut acreage was not correlated with peanut yield, spray volume, and spray pressure.
Co‐applying three or more products in the same tank was common among growers.
Flat‐fan nozzles were the most commonly used spray nozzles among peanut growers.
Growers spend approximately 18% of their time applying crop protection products.
}, number={1}, journal={CROP FORAGE & TURFGRASS MANAGEMENT}, author={Jordan, David L. and Hare, Andrew T. and Roberson, Gary T. and Shew, Barbara B. and Brandenburg, Rick L. and Anco, Dan and Balota, Maria and Mehl, Hillary and Taylor, Sally}, year={2018}, month={Oct} }
 @article{foote_edmisten_wells_collins_roberson_jordan_fisher_2016, title={Influence of nitrogen and mepiquat chloride on cotton canopy reflectance measurements}, volume={20}, number={1}, journal={Journal of Cotton Science}, author={Foote, W. and Edmisten, K. and Wells, R. and Collins, G. and Roberson, G. and Jordan, D. and Fisher, L.}, year={2016}, pages={1–7} }
 @article{roberson_jordan_2014, title={RTK GPS and automatic steering for peanut digging}, volume={30}, DOI={10.13031/aea.30.10432}, abstractNote={Abstract. Peanut harvesting is a two-stage process. In the first stage, a digger-shaker-inverter implement is used to plow peanut from the ground. In the second stage, a combine is used to thresh peanut pods from the vines. Yield loss can be significant, especially during the digging stage where the implement may not be properly aligned over the rows of peanut. In this study, RTK-based automatic steering was compared to manual steering to determine the potential for reduced yield losses. In addition, peanut response to the plant growth regulator prohexadione calcium was compared to a non-treated peanut to determine if reduced yield losses were obtainable. Prohexadione calcium regulator did not improve yield significantly. However, use of RTK based automatic steering was significant, increasing harvested yield by 510 kg/ha or 11%.}, number={3}, journal={Applied Engineering in Agriculture}, author={Roberson, Gary and Jordan, D. L.}, year={2014}, pages={405–409} }
 @article{thompson_brandenburg_roberson_lineberger_2008, title={A technique to monitor insect behavior utilizing infrared emitters and detectors}, volume={43}, ISSN={["0749-8004"]}, DOI={10.18474/0749-8004-43.1.143}, number={1}, journal={JOURNAL OF ENTOMOLOGICAL SCIENCE}, author={Thompson, Sarah R. and Brandenburg, Rick L. and Roberson, Gary T. and Lineberger, Barry}, year={2008}, month={Jan}, pages={143–152} }
 @article{grisso_vaughan_roberson_2008, title={Fuel prediction for specific tractor models}, volume={24}, DOI={10.13031/2013.25139}, abstractNote={Generalized models for fuel consumption are useful for budget and management scenarios, but may not have the ability to compare fuel consumption for several potential tractor configurations such as turbocharging and air densification models. The objective of this article is to develop a method that uses the Nebraska Tractor Test Lab (NTTL) data for a specific tractor model to predict fuel consumption for full and partial loads and for reduced throttle conditions. Using these equations, the fuel savings can be predicted for different operating and loading conditions. This method is compared with the generalized model and actual NTTL fuel consumption data. The results showed that 88% of tractors had an improved prediction with the new methodology.}, number={4}, journal={Applied Engineering in Agriculture}, author={Grisso, R. D. and Vaughan, D. H. and Roberson, Gary}, year={2008}, pages={423–428} }
 @article{thompson_brandenburg_roberson_2007, title={Entomopathogenic fungi detection and avoidance by mole crickets (Orthoptera : Gryllotalpidae)}, volume={36}, ISSN={["1938-2936"]}, DOI={10.1603/0046-225X(2007)36[165:EFDAAB]2.0.CO;2}, abstractNote={Abstract A chamber to monitor mole cricket behavior was designed using two different soil-filled containers and photosensors constructed from infrared emitters and detectors. Mole crickets (Scapteriscus spp.) were introduced into a center tube that allowed them to choose whether to enter and tunnel in untreated soil or soil treated with Beauveria bassiana (Balsamo) Vuillemin. Each time the cricket passed through the photosensor located near the entrance of soil-filled containers, the infrared light was blocked and the exact moment that this occurred was logged onto a computer using custom-written software. Data examined included the first photosensor trigger, total number of sensor triggers, presence of tunneling, and final location of the cricket after 18 h. These behaviors were analyzed to discern differences in mole cricket behavior in the presence of different treatments and to elucidate the mechanism that mole crickets use to detect fungal pathogens. The first study examined substrate selection and tunneling behavior of the southern mole cricket, Scapteriscus borellii Giglio-Tos, to the presence of five strains of B. bassiana relative to a control. There were no differences between the first sensor trigger and total number of triggers, indicating the mole crickets are not capable of detecting B. bassiana at a distance of 8 cm. Changes in mole cricket tunneling and residence time in treated soil occurred for some strains of B. bassiana but not others. One of the strains associated with behavioral changes in the southern mole cricket was used in a second experiment testing behavioral responses of the tawny mole cricket, S. vicinus Scudder. In addition to the formulated product of this strain, the two separate components of that product (conidia and carrier) and bifenthrin, an insecticide commonly used to control mole crickets, were tested. There were no differences in mole cricket behavior between treatments in this study. The differences in behavioral responses between the two species could suggest a more sensitive chemosensory recognition system for southern mole crickets.}, number={1}, journal={ENVIRONMENTAL ENTOMOLOGY}, author={Thompson, Sarah R. and Brandenburg, Rick L. and Roberson, Gary T.}, year={2007}, month={Feb}, pages={165–172} }
 @article{wilkerson_price_bennett_krueger_roberson_robinson_2004, title={Evaluating the potential for site-specific herbicide application in soybean}, volume={18}, ISSN={["0890-037X"]}, DOI={10.1614/WT-03-258R}, abstractNote={Field experiments were conducted on two North Carolina research stations in 1999, 2000, and 2001; on-farm in Lenoir, Wayne, and Wilson counties, NC, in 2002; and on-farm in Port Royal, VA, in 2000, 2001, and 2002 to evaluate possible gains from site-specific herbicide applications at these locations. Fields were scouted for weed populations using custom software on a handheld computer linked to a Global Positioning System. Scouts generated field-specific sampling grids and recorded weed density information for each grid cell. The decision aid HADSS™ (Herbicide Application Decision Support System) was used to estimate expected net return and yield loss remaining after treatment in each sample grid of every field under differing assumptions of weed size and soil moisture conditions, assuming the field was planted with either conventional or glyphosate-resistant (GR) soybean. The optimal whole-field treatment (that treatment with the highest expected net return summed across all grid cells within a field) resulted in average theoretical net returns of $79/ha (U.S. dollars) and $139/ha for conventional and GR soybean, respectively. When the most economical treatment for each grid cell was used in site-specific weed management, theoretical net returns increased by $13/ha (conventional) and $4.50/ha (GR), and expected yield loss after treatment was reduced by 10.5 and 4%, respectively, compared with the whole-field optimal treatment. When the most effective treatment for each grid cell was used in site-specific weed management, theoretical net returns decreased by $18/ha (conventional) and $4/ha (GR), and expected yield loss after treatment was reduced by 27 and 19%, respectively, compared with the whole-field optimal treatment. Site-specific herbicide applications could have reduced the volume of herbicides sprayed by as much as 70% in some situations but increased herbicide amounts in others. On average, the whole-field treatment was optimal in terms of net return for only 35% (conventional) and 57% (GR) of grid cells.}, number={4}, journal={WEED TECHNOLOGY}, author={Wilkerson, GG and Price, AJ and Bennett, AC and Krueger, DW and Roberson, GT and Robinson, BL}, year={2004}, pages={1101–1110} }
 @article{jordan_barnes_bogle_naderman_roberson_johnson_2001, title={Peanut response to tillage and fertilization}, volume={93}, ISSN={["1435-0645"]}, DOI={10.2134/agronj2001.9351125x}, abstractNote={Peanut (Arachis hypogaea L.) in the USA is generally seeded after several primary tillage operations that may include disking, chisel plowing, moldboard plowing, and bedding (conventional tillage systems). Concerns over erosion and production costs have increased interest in reduced tillage systems. Production in reduced tillage systems minimizes ability to incorporate fertilizers below the pegging zone, and residue on soil surface could impact movement of calcium sulfate (CaSO4) into the soil, reducing Ca availability to pegs. Research was conducted from 1997 through 1999 to compare peanut yield and gross economic value of virginia market type peanut planted in conventional and strip tillage systems. Preplant fertilizer did not affect response to tillage. Response did not differ among conventional tillage systems consisting of disk, disk and chisel, or disk and moldboard plow or among reduced tillage systems. Pod yield of peanut grown in the most effective conventional tillage system exceeded yield when peanut was strip‐tilled into stubble of the previous crop, strip‐tilled into a wheat (Triticum aestivum L.) cover crop, or strip‐tilled into beds prepared the previous fall without a cover crop. Tillage system and CaSO4 rate affected pod yield and gross value independently. Gross value increased when CaSO4 was applied regardless of tillage system. These data suggest that preplant fertilizer at relatively low, remedial rates does not affect peanut response to tillage systems. These data also suggest that tillage system does not have a major impact on peanut response to CaSO4. Collectively, these data indicate that the highest peanut yields occur in conventional tillage systems.}, number={5}, journal={AGRONOMY JOURNAL}, author={Jordan, DL and Barnes, JS and Bogle, CR and Naderman, GC and Roberson, GT and Johnson, PD}, year={2001}, pages={1125–1130} }
 @article{roberson_2000, title={Precision agriculture technology for horticultural crop production.}, volume={10}, DOI={10.21273/horttech.10.3.448}, abstractNote={Precision agriculture is a comprehensive system that relies on information, technology and management to optimize agricultural production. While used since the mid-1980s in agronomic crops, it is attracting increasing interest in horticultural crops. Relatively high per acre crop values for some horticultural crops and crop response to variability in soil and nutrients makes precision agriculture an attractive production system. Precision agriculture efforts in the Department of Biological and Agricultural Engineering at North Carolina State University are currently focused in two functional areas: site-specific management and postharvest process management. Much of the information base, technology, and management practices developed in agronomic crops have practical and potentially profitable applications in fruit and vegetable production. Mechanized soil sampling, pest scouting and variable rate control systems are readily adapted to horticultural crops. Yield monitors are under development for many crops that can be mechanically harvested. Investigations have begun to develop yield monitoring capability for hand harvested crops. Postharvest controls are widely used in horticultural crops to enhance or protect product quality.}, number={3}, journal={HortTechnology}, author={Roberson, Gary}, year={2000}, pages={448–451} }
 @article{crouse_havlin_mcbride_white_heiniger_weisz_roberson_2000, title={Precision farming education at NC State University}, journal={Proceedings of the 5th International conference on precision agriculture, Bloomington, Minnesota, USA, 16-19 July, 2000}, publisher={Madison, WI : Precision Agriculture Center, University of Minnesota, ASA-CSSA-SSSA}, author={Crouse, D. A. and Havlin, J. L. and McBride, R. G. and White, J. G. and Heiniger, R. and Weisz, R. and Roberson, G.}, year={2000}, pages={1} }
 @article{roberson_lyons_1992, title={Comprehensive management, operation, and maintenance training for farm machinery}, number={92-1041}, journal={Paper (American Society of Agricultural Engineers)}, author={Roberson, G. T. and Lyons, D. M.}, year={1992}, pages={9} }
 @article{roberson_suggs_1991, title={Construction and evaluation of a chainsaw kickback simulator}, volume={7}, DOI={10.13031/2013.26224}, abstractNote={A simulator for evaluating chainsaw kickback was constructed using mechanical elements to replicate the human upper body. The simulator, dubbed ADAM (Applied Dynamic Anthropometric Model), was intended to match the anthropometric properties of the 50th percentile adult male. Kickback was produced by means of a companion device which consisted of a V-grooved wheel rotating at speeds approaching chain speed and having approximately the same rotational inertia as a small to medium sized chain saw. Kickbacks were generated as a result of contact between the bar of a nonrunning saw and the wheel.}, number={2}, journal={Applied Engineering in Agriculture}, author={Roberson, Gary and Suggs, C. W.}, year={1991}, pages={153} }