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UF/IFAS Citrus Research and Education Center

UF/IFAS Citrus Research and Education Center

Publications - Dr. Arnold Schumann


Websites

Refereed Journal Articles

Ebert T.A., Waldo L., Stanton D., Schumann A. (2020) Screen Mesh Size for Exclusion of Diaphorina citri (Hemiptera: Liviidae) in Citrus Production. Journal of Economic Entomology https://doi.org/10.1093/jee/toaa095

Etxeberria E., Gonzalez P., Vincent C., Schumann A. (2019) Extended persistence of Candidatus Liberibacter asiaticus (CLas) DNA in Huanglongbing-affected citrus tissue after bacterial death. Physiological and Molecular Plant Pathology 106:204-207.

Farooque A., Zare M., Zaman Q., Abbas F., Bos M., Esau T., Acharya B., Schumann A. (2019) Evaluation of DualEM-II sensor for soil moisture content estimation in the potato fields of Atlantic Canada. Plant, Soil and Environment 65:290-297.

Rehman T.U., Zaman Q.U., Chang Y.K., Schumann A.W., Corscadden K.W. (2019) Development and field evaluation of a machine vision based in-season weed detection system for wild blueberry. Computers and Electronics in Agriculture 162:1-13.

Schumann A.W., Mood N.S., Mungofa P.D., MacEachern C., Zaman Q., Esau T. (2019) Detection of Three Fruit Maturity Stages in Wild Blueberry Fields Using Deep Learning Artificial Neural Networks, 2019 ASABE Annual International Meeting, American Society of Agricultural and Biological Engineers, St. Joseph, MI. pp. pp. 4.

Sharpe S.M., Schumann A.W., Boyd N.S. (2020) Goosegrass Detection in Strawberry and Tomato Using a Convolutional Neural Network. Scientific Reports 10:9548. https://doi.org/10.1038/s41598-020-66505-9

Sharpe S., Schumann A., Yu J., Boyd N. (2020) Vegetation detection and discrimination within vegetable plasticulture row-middles using a convolutional neural network. Precision Agriculture 21:264-277.

Yu J., Sharpe S.M., Schumann A.W., Boyd N.S. (2019) Deep learning for image-based weed detection in turfgrass. European journal of agronomy 104:78-84.

Yu J., Sharpe S.M., Schumann A.W., Boyd N.S. (2019) Detection of broadleaf weeds growing in turfgrass with convolutional neural networks. Pest management science 75:2211-2218.

Yu J., Schumann A.W., Cao Z., Sharpe S.M., Boyd N.S. (2019) Weed Detection in Perennial Ryegrass With Deep Learning Convolutional Neural Network. Frontiers in plant science 10. https://doi.org/10.3389/fpls.2019.01422

Morgan, K.T., D. M. Kadyampakeni, M. Zekri, A. W. Schumann, T. Vashisth, B. Boman, and A. Obreza. 2019. 2018–2019. Florida Citrus Production Guide: Fertilizer Application Methods. http://edis.ifas.ufl.edu/cg09

Ali, S., Q. Zaman, A. Farooque, A. Schumann, C. Udenigwe, T. Esau, and Y. Ki Chang. 2018. Potential use of digital photographic technique to examine wild blueberry ripening in relation to time of harvest. Applied Engineering in Agriculture 34: 299-308. https://doi.org/10.13031/aea.12490

Boyd, N. S., and A. Schumann. 2018. Development and Evaluation of a Hole-Punch Applicator for Precision Application of Preemergence Herbicides in Plasticulture Production. Weed Technology: 1-5. https://doi.org/10.1017/wet.2018.100

Boyd, N., and A. W. Schumann. 2018. Hole-punch technology dramatically reduces herbicide use, pp. 1, Vegetable and Specialty Crop News. Agnet Media, Gainesville, FL.

Esau, K., T. Esau, Q. Zaman, A. Farooque, and A. Schumann. 2018. Effective use of a variable speed blower fan on a mechanical wild blueberry harvester. Applied Engineering in Agriculture 34: 831-840. https://doi.org/10.13031/aea.12818

Esau, T., Q. Zaman, D. Groulx, A. Farooque, A. Schumann, and Y. Chang. 2018. Machine vision smart sprayer for spot-application of agrochemical in wild blueberry fields. Precision Agriculture 19: 770-788.  https://doi.org/10.1007/s11119-017-9557-y        

Ferrarezi, R. S., A. Wright, and A. W. Schumann. 2018. Increasing yield through high-density plantings, pp. 8-12, Citrus Industry. Southeast Agnet, Ocala, FL. http://citrusindustry.net/2018/11/19/

Kadyampakeni, D. M., K. T. Morgan, M. Zekri, R. S. Ferrarezi, A. W. Schumann, and T. Obreza. 2018. Current considerations for citrus irrigation management, pp. 6-11, Citrus Industry. Southeast Agnet, Ocala, FL. http://citrusindustry.net/

Kadyampakeni, D. M., K. T. Morgan, P. Nkedi-Kizza, A. W. Schumann, and J. W. Jawitz. 2018. Modeling Water and Nutrient Movement in Sandy Soils Using HYDRUS-2D. Journal of Environmental Quality. https://doi.org/10.2134/jeq2018.02.0056

Mungofa, P., A. Schumann, and L. Waldo. 2018. Chemical crystal identification with deep learning machine vision. BMC research notes 11: 1-6. https://doi.org/10.1186/s13104-018-3813-8

Rehman, T. U., Q. U. Zaman, Y. K. Chang, A. W. Schumann, K. W. Corscadden, and T. J. Esau. 2018. Optimising the parameters influencing performance and weed (goldenrod) identification accuracy of color co-occurrence matrices. Biosystems Engineering 170: 85-95. https://doi.org/10.1016/j.biosystemseng.2018.04.002

Schumann, A., A. Singerman, A.L., Wright, R. Ferrarezi. 2018. Citrus Under Protective Screen (CUPS) Production Systems. http://edis.ifas.ufl.edu/hs1304

Schumann, A. W., L. Waldo, D. M. Kadyampakeni, R. S. Ferrarezi, and C. Oswalt. 2018. Using soil moisture sensors for citrus irrigation, pp. 12-15, Citrus Industry. Southeast Agnet, Ocala, FL. http://citrusindustry.net/2018/07/10/

Schumann, A. W., L. Waldo, W. Holmes, G. Test, and T. E. Ebert. 2018. Artificial intelligence for detecting citrus pests, diseases and disorders, pp. 6-10, Citrus Industry. Southeast Agnet, Ocala, FL. http://citrusindustry.net/2018/07/02/

Schumann, A. W., Q. U. Zaman, H. S. Chatta, S. Read, and A. Farooque. 2018. Precision application of dry fertilizer in wild blueberry fields, pp. 1, Vegetable and Specialty Crop News. Agnet Media, Gainesville, FL. http://vscnews.com/precision-application

Schumann, A. W., T. E. Ebert, L. Waldo, W. Holmes, N. Mariner, G. Test, C. Oswalt, R. S. Ferrarezi, and R. Lesmes. 2018. Research update: citrus under protective screen, pp. 14-19, Citrus Industry. Southeast Agnet, Ocala, FL. http://citrusindustry.net/2018/11/26/

Sharpe, S., A. Schumann, and N. Boyd. 2018. Detection of Carolina Geranium ( Geranium carolinianum ) Growing in Competition with Strawberry Using Convolutional Neural Networks. Weed Science: 1-7. https://doi.org/10.1017/wsc.2018.66

Zekri, M., T. Obreza, and A. Schumann. 2018. Increasing Efficiency and Reducing Costs of Citrus Nutritional Programs. https://edis.ifas.ufl.edu/ss442

Jamie D. Burrow, J.D., T. Vashisth, M. Zekri, S. H. Futch, and A. Schumann. 2017. Citrus nutrition management practices. http://edis.ifas.ufl.edu/hs1292

Chang, Y., Q. Zaman, A. Farooque, H. S. Chattha, S. M. Read, and A. Schumann. 2017. Sensing and control system for the spot-application of fertilizer in wild blueberry cropping system. Precision Agriculture 18: 210–223. https://doi.org/10.1007/s11119-016-9457-6

Esau, T., Q. Zaman, D. Groulx, Y. Chang, A. W. Schumann, and P. Havard. 2017. Supplementary light source development for camera-based smart spraying in low light conditions. Applied Engineering in Agriculture 33: 5-14 https://doi.org/10.13031/aea.11678

Farooque, A. A., Q. Uz Zaman, T. Esau, Y. Ki Chang, A. W. Schumann, and W. Jameel. 2017. Influence of Wild Blueberry Fruit Yield, Plant Height, and Ground Slope on Picking Performance of a Mechanical Harvester: Basis for Automation. Applied Engineering in Agriculture 33: 655-666. https://doi.org/10.13031/aea.12187

Farooque, A., Q. Zaman, A. W. Schumann, and T. Esau. 2017. Precision Agriculture in Lime: Potential for Application of Precision Agriculture Technologies in Lime Cropping Systems, pp. 135-148. In M. Mumtaz Khan (ed.), The Lime: Botany, Production, and Uses, vol. 1. CAB International, Boston, MA.         

Ferrarezi, R. S., A. Wright, B. J. Boman, A. W. Schumann, F. G. Gmitter, and J. W. Grosser. 2017. Protected fresh grapefruit cultivation Systems: Antipsyllid screen effects on environmental variables inside enclosures. HortTechnology 27: 675-681. https://doi.org/10.21273/HORTTECH03790-17

Ferrarezi, R. S., A. Wright, B. J. Boman, A. W. Schumann, F. G. Gmitter, and J. W. Grosser. 2017. Protected fresh grapefruit cultivation systems: Antipsyllid screen effects on plant growth and leaf transpiration, vapor pressure deficit, and nutrition. HortTechnology 27: 666-674. https://doi.org/10.21273/HORTTECH03789-17

Kadyampakeni, D. M., K. T. Morgan, M. Zekri, R. S. Ferrarezi, A. Schumann, and T. Obreza. 2017. Irrigation Management of Citrus Trees - 2017-2018 Florida Citrus Production Guide.

Kadyampakeni, D., K. Morgan, M. Zekri, R. Ferrarezi, A. Schumann, and T. Obreza. 2017. Citrus irrigation management. http://edis.ifas.ufl.edu/ss660

Davie Kadyampakeni, Kelly Morgan, Mongi Zekri, Rhuanito Ferrarezi, Arnold Schumann, and Thomas A. Obreza. 2017. Irrigation management of HLB-affected trees. https://edis.ifas.ufl.edu/ss659

Kadyampakeni, D. M., P. Nkedi-Kizza, K. T. Morgan, and A. W. Schumann. 2017. Characterizing sorption and modeling phosphorus movement on Candler and Immokalee fine sand. Journal of Soil and Water Science 1: 8-14.  NA

Morgan, K. T., D. Kadyampakeni, M. Zekri, A. Schumann, T. Vashisth, and T. Obreza. 2017. Nutrition Management for Citrus Trees - 2017-2018 Florida Citrus Production Guide PDF

Schumann, A. W., and L. Waldo. 2017. Update on citrus undercover production systems research, pp. 16-20, Citrus Industry. Southeast Agnet, Ocala, FL. http://citrusindustry.net/2017/11/08/

Schumann, A. W., and L. Waldo. 2017. Understanding Soil-Moisture Sensor Data, pp. 6-11, Citrus Industry. Southeast Agnet, Ocala, FL. http://citrusindustry.net/2017/07/10/

Schumann, A., A. Singerman, A. Wright, and R. S. Ferrarezi. 2017. Citrus Under Protective Screen (CUPS) Production Systems. https://edis.ifas.ufl.edu/hs1304

Schumann, A., T. Vashisth, and T.M. Spann. 2017. Mineral Nutrition Contributes to Plant Disease and Pest Resistance. https://edis.ifas.ufl.edu/hs1181

Zekri, M., A. Schumann, T. Vashisth, D. Kadyampakeni, K. Morgan, B. Boman, and T. Obreza. 2017. Fertigation for citrus trees. http://edis.ifas.ufl.edu/hs1306

Abbas, A., Q. U. Zaman, A. A. Farooque, A. W. Schumann, G. R. Brewster, and R. Donald. 2016. Effect of split variable rate fertilization on wild blueberry plant growth and berry yield. Applied Engineering in Agriculture 32: 675-683. https://doi.org/10.13031/aim.20152189139

Abbas, A., Q. Zaman, A. W. Schumann, A. A. Farooque, G. Brewster, and R. Donald. 2016. Effect of Split Fertilization on Subsurface Water Quality in Wild Blueberry Fields. Applied Engineering in Agriculture 32: 79-88. https://doi.org/10.13031/aea.32.11248

Chang, Y., Q. Zaman, A. Farooque, H. S. Chattha, S. M. Read, and A. Schumann. 2016. Sensing and control system for the spot-application of fertilizer in wild blueberry cropping system. Precision Agriculture. https://doi.org/10.1007/s11119-016-9457-6

Esau, T., Q. Zaman, D. Groulx, K. Corscadden, Y. Chang, A. W. Schumann, and P. Havard. 2016. Economic analysis for smart sprayer application in wild blueberry fields. Precision Agriculture 47: pp. 1-13. https://doi.org/10.1007/s11119-016-9447-8

Farooque, A. A., Q. Zaman, D. Groulx, A. W. Schumann, and T. N. Quang. 2016. Response of Wild Blueberry Fruit Loss to Spatial Variability in Crop Characteristics and Slope of the Field. Applied Engineering in Agriculture 32: 493-504. https://doi.org/10.13031/aea.32.11352

Farooque, A. A., Q. Zaman, T. N. Quang, D. Groulx, A. W. Schumann, and Y. K. Chang. 2016. Development of a Predictive Model for Wild Blueberry Harvester Fruit Losses during Harvesting Using Artificial Neural Network. Applied Engineering in Agriculture 32: 739-749. https://doi.org/10.13031/aea.32.10872

Farooque, A. A., Q. Zaman, Y. K. Chang, K. W. Corscadden, A. W. Schumann, H. S. Chattha, A. Madani, and A. Abbas. 2016. Influence of Soil Properties and Topographic Features on Wild Blueberry Fruit Yield. Applied Engineering in Agriculture 32: 725-738. https://doi.org/10.13031/aea.32.11137

Jameel, M. W., Q. Zaman, A. W. Schumann, T. N. Quang, A. A. Farooque, G. R. Brewster, and H. S. Chattha. 2016. Effect of Plant Characteristics on Picking Efficiency of the Wild Blueberry Harvester. Applied engineering in Agriculture 32: 589-598. https://doi.org/10.13031/aea.32.11492

Kadyampakeni, D. M., K. T. Morgan, and A. W. Schumann. 2016. Biomass, Nutrient Accumulation and Tree Size Relationships for Drip- And Micosprinkler-Irrigated Orange Trees. Journal of Plant Nutrition 39: 589-599. https://doi.org/10.1080/01904167.2015.1009112

Khan, F., Q. Zaman, Y. Chang, A. Farooque, A. Schumann, and A. Madani. 2016. Estimation of the rootzone depth above a gravel layer (in wild blueberry fields) using electromagnetic induction method. Precision Agriculture 17: 155-167. https://doi.org/10.1007/s11119-015-9413-x

Schumann, A. W., and A. Singerman. 2016. The economics of citrus undercover production systems and whole tree thermotherapy, pp. 14-18, Citrus Industry. Southeast Agnet, Ocala, FL. PDF

Schumann, A. W., and L. Waldo. 2016. CUPS Quick Start Guide, pp. 13. In A. W. Schumann [ed.], Interim Sustainable Solutions for Fresh Citrus Fruit Production in Florida UF/IFAS CREC, Lake Alfred, FL.

Schumann, A. W., L. Waldo, and A. Wright. 2016. Citrus Undercover Production Systems (CUPS) and Whole Tree Thermotherapy (WTT), pp. 8-13, Citrus Industry. Southeast Agnet, Ocala, FL. http://citrusindustry.net/2016/12/26/

Chatta, H. S., Zaman, Y. K. Chang, A. A. Farooque, A. W. Schumann, and G. Brewster. 2015. Effect of lighting conditions and ground speed on performance of intelligent fertilizer spreader for spot-application in wild blueberry. Precision Agriculture 16: 654-667. https://doi.org/10.1007/s11119-015-9400-2

Gruber, B., B. Boman, S. A, H. K. Hostler, and L. Waldo. 2015. Methods for profitable citrus production pp. 10-12, Citrus Industry. Southeast Agnet, Ocala, FL. PDF

Khan, F. S., Q. U. Zaman, Y. K. Chang, A. A. Farooque, A. W. Schumann, and A. Madani. 2015. Estimation of the rootzone depth above a gravel layer (in wild blueberry fields) using electromagnetic induction method. Precision Agriculture DOI 10.1007/s11119-015-9413-x: 1-13. https://doi.org/10.1007/s11119-015-9400-2

Schumann, A. 2015. Chemical concepts in HLB mitigation programs, pp. 20-23, Citrus Industry. Southeast Agnet, Ocala, FL.

Zekri, M., M. KT, T. Obreza, and A. Schumann. 2015. Leaf tissue and soil sampling and testing, pp. 27-29, Citrus Industry. Southeast Agnet, Ocala, FL.

Zekri, M., T. Obreza, and A. Schumann. 2015. Increasing Efficiency and Reducing Cost of Nutritional Programs, pp. 22-25, Citrus Industry. Southeast Agnet, Ocala, FL.

Abbas, A., Q. U. Zaman, A. W. Schumann, G. Brewster, R. Donald, and H. S. Chattha. 2014. Effect of split variable rate fertilization on ammonia volatilization in wild blueberry cropping system. Applied Engineering in Agriculture 30: 619-627. https://doi.org/10.13031/aea.30.10592

Campos-Herrera, R., F. E. El-Borai, T. E. Ebert, A. W. Schumann, and L. W. Duncan. 2014. Management to control citrus greening alters the soil food web and severity of a pest-disease complex. Biological Control 76: 41-51. https://doi.org/10.1016/j.biocontrol.2014.04.012

Chang, Y. K., Q. Zaman, T. Esau, and A. W. Schumann. 2014. Sensing system using digital photography technique for spot-application of herbicide in pruned wild blueberry fields. Applied Engineering in Agriculture 30: 143-152. https://doi.org/10.13031/aea.30.10181

Chatta, H. S., Q. U. Zaman, Y. K. Chang, S. Read, A. W. Schumann, G. R. Brewster, and A. A. Farooque. 2014. Variable rate spreader for real-time spot-application of granular fertilzer in wild blueberry. Computers and Electronics in Agriculture 100: 70-78. https://doi.org/10.1016/j.compag.2013.10.012

Chattha, H. S., Q. U. Zaman, Y. K. Chang, S. Read, A. W. Schumann, G. R. Brewster, and A. A. Farooque. 2014. Variable rate spreader for real-time spot-application of granular fertilizer in wild blueberry. Computers and Electronics in Agriculture 100: 70-78.

Esau, T. J., Q. U. Zaman, Y. K. Chang, D. Groulx, A. W. Schumann, and A. A. Farooque. 2014. Prototype variable rate sprayer for spot-application of agrochemicals in wild blueberry. Applied Engineering in Agriculture 30: 717-725. https://doi.org/10.13031/aea.30.10613

Esau, T. J., Q. U. Zaman, Y. K. Chang, A. W. Schumann, D. C. Percival, and A. A. Farooque. 2014. Spot-application of fungicide for wild blueberry using an automated prototype variable rate sprayer. Precision Agriculture 15: 147-161. https://doi.org/10.1007/s11119-013-9319-4

Farooque, A., Q. U. Zaman, D. Groulx, A. W. Schumann, D. E. Yarborough, and T. Nguyen-Quang. 2014. Effect of ground speed and header revolutions on the picking efficiency of a commercial blueberry harvester. Applied Engineering in Agriculture 30: 535-546. http://dx.doi.org/10.13031/aim.20131596449

Kadyampakeni, D. M., K. T. Morgan, A. W. Schumann, and P. Nkedi-Kizza. 2014. Effect of irrigation pattern and timing on root density of young citrus trees infected with huanglongbing disease. HortTechnology 24: 209-221. https://doi.org/10.21273/HORTTECH.24.2.209

Kadyampakeni, D. M., K. T. Morgan, A. W. Schumann, P. Nkedi-Kizza, and K. Mahmoud. 2014. Ammonium and nitrate distribution in the soil using drip and microsprinkler irrigation for citrus production. Soil Science Society of America Journal 78: 645-654. https://doi.org/10.2134/cs2014-47-3-9

Kadyampakeni, D. M., K. T. Morgan, A. W. Schumann, P. Nkedi-Kizza, and T. A. Obreza. 2014. Water Use in Drip- and Microsprinkler-Irrigated Citrus Trees. Soil Science Society of America Journal 78: 1351-1361. https://doi.org/10.2136/sssaj2014.02.0054

Kadyampakeni, D. M., K. T. Morgan, K. Mahmoud, A. W. Schumann, and P. Nkedi-Kizza. 2014. Phosphorus and Potassium Distribution and Adsorption on Two Florida Sandy Soils. Soil Science Society of America Journal 78: 325-334. https://doi.org/10.2136/sssaj2013.07.0259

Saleem, S. R., Q. Zaman, A. W. Schumann, A. Madani, Y. K. Chang, and A. A. Farooque. 2014. Impact of variable rate fertilization on nutrients losses in surface runoff for wild blueberry fields. Applied Engineering in Agriculture 30: 179-185. https://doi.org/10.13031/aea.30.10346

Campos Herrera, R., E. Pathak, F.E. El-Borai, A.W. Schumann, M.M. Abd-Elgawad, L.W. Duncan. 2013. New citriculture system suppresses native and augmented entomopathogenic nematodes. Biological Control 66: 183-194. https://doi.org/10.1016/j.biocontrol.2013.05.009

Esau, T., Q. Zaman, Y. Chang., A. Schumann, A. Farooque, and D. Percival. 2013. Spot-application of fungicide for wild blueberry using an automated prototype variable rate sprayer. Precision Agriculture On-line. https://doi.org/10.1007/s11119-013-9319-4

Farooque, A., Y. Chang, Q. Zaman, D. Groulx, A. Schumann, and T. Esau. 2013. Performance evaluation of multiple ground based sensors mounted on a commercial wild blueberry harvester to sense plant height, fruit yield, and topographic features in real-time. Computers and Electronics in Agriculture 91: 135-144. https://doi.org/10.1016/j.compag.2012.12.006

Gruber, B., B. Boman, and A. W. Schumann. 2013. Citrus production research at the UF-IFAS IRREC, pp. 6-7, Citrus Industry. Southeast Agnet, Ocala, FL.      NA

Saleem, S., Q. Zaman, A. Schumann, A. Madani, A. Farooque, and D. Percival. 2013. Impact of variable rate fertilization on subsurface water contamination in wild blueberry cropping system. Applied Engineering in Agriculture 29: 225-232.
https://doi.org/10.13031/2013.37256

Saleem, S., Q. Zaman, A. Schumann, A. Madani, D. Percival, and A. Farooque. 2013. Impact of Variable Rate Fertilization on Wild Blueberry Plant Growth and Fruit Yield. Applied Engineering in Agriculture 29: 683-690. https://doi.org/10.13031/aea.29.10112

Schumann, A. W., H. K. Hostler, L. Waldo, and N. Rayburn. 2013. Update on advanced citrus production systems (ACPS) trials, pp. 22-27, Citrus Industry. Southeast Agnet, Ocala, F. PDF

Chang, Y., Q. U. Zaman, A. Farooque, A. W. Schumann, and D. C. Percival. 2012. An Automated Yield Monitoring System II for Commercial Wild Blueberry Double-Head Harvester. Computers and Electronics in Agriculture 81: 97-103. https://doi.org/10.1016/j.compag.2011.11.012

Chang, Y., Q. U. Zaman, A. W. Schumann, D. C. Percival, T. J. Esau, and G. Aylew. 2012. Development of Color Co-occurrence Matrix Based Machine Vision Algorithms for Wild Blueberry Fields. Applied Engineering in Agriculture 28: 315-323. https://doi.org/10.13031/2013.42321

Farooque, A., Q. Zaman, A. Schumann, A. Madani, and D. Percival. 2012. Delineating management zones for site-specific fertilization in wild blueberry fields. Applied Engineering in Agriculture 28: 57-70.      

Farooque, A., Q. Zaman, A. Schumann, A. Madani, and D. Percival. 2012. Response of wild blueberry yield to spatial variability of soil properties. Soil Science 177: 56-68. https://doi.org/10.1097/SS.0b013e3182376ed6

Mann, K.K., A. W. Schumann, T. A. Obreza, W. G. Harris, and J. B. Sartain. 2017. How to Characterize Soil Variability in Florida Citrus Groves as It Relates to Tree Growth and Yield https://edis.ifas.ufl.edu/ss557

Schumann, A. W. 2012. Phosphorus, phosphate and phosphite explained, pp. 12-15, Citrus Industry. Southeast Agnet, Ocala, FL. http://griffinfertilizer.com/

Schumann, A. W. a. T. S. 2012. Opportunities for biochar production and use in Florida citrus, pp. 6-9, Citrus Industry. Southeast Agnet, Ocala, FL. PDF

Schumann, A. W., K.H. Hostler, L. Waldo, K.K. Mann. 2012. Advanced Production Systems for Florida citrus: research update, huanglongbing impacts and production forecasts, pp. 6-12, Citrus Industry. Southeast Agnet, Ocala, FL.

Schumann, A. W., K.H. Hostler, L. Waldo. 2012. Advanced Citrus Production Systems - grove designs for higher efficiencies, pp. 6-9, Citrus Industry. Southeast Agnet, Ocala, FL. PDF

Spann, T., and A.W. Schumann. 2012. Using good horticultural practices to maintain yield of HLB-affected groves, pp. 6-11, Citrus Industry. Southeast Agnet, Ocala, FL.

Mann, K. K., A. W. Schumann, and T. M. Spann. 2011. Balanced mineral nutrition decreases greasy spot incidence in citrus, pp. 123-130. In, Proc. FSHS, 2011, St. Petersburg, FL. ASHS.

Mann, K. K., A. W. Schumann, and T. M. Spann. 2011. Response of citrus to exogenously applied salicylate compounds during abiotic and biotic stresses, pp. 101-110. In, Proc. FSHS, 2011, St. Petersburg, FL. ASHS. http://fshs.org/proceedings-o/2011-vol-124/

Mann, K. K., A.W. Schumann, T.A. Obreza, J.B. Sartain, W.G. Harris, and S. Shukla 2011. Analyzing the efficiency of soil amendments and irrigation for plant production on heterogeneous sandy soils under greenhouse conditions. Journal of Plant Nutrition and Soil Science 174: 925-932. https://doi.org/10.1002/jpln.201000350

Mann, K. K., A.W. Schumann, T.A. Obreza, M. Teplitski, W.G. Harris, and J.B. Sartain. 2011. Spatial Variability of Soil Chemical and Biological Properties in Florida Citrus Production. Soil Science Society of America Journal 75: 1863-1873.       

Saleem, S. R., Q.U. Zaman, A.W. Schumann, A. Madani, D.C. Percival, A.A. Farooque, F.S. Khan, S. Read. 2011. Impact of Variable Rate Fertilization on Ground Water Contamination in Wild Blueberry Cropping System, pp. 11, ASABE Annual International Meeting. ASABE, Louisville, KY. https://doi.org/10.13031/2013.37256

Schumann, A. W., H. K. Hostler, K. K. Mann, L. J. Waldo, and J. Strang. 2011. Update on the Advanced Citrus Production System in Florida, p. 11. In, Proc. FSHS, 2011, St. Petersburg, FL. ASHS.            

Schumann, A. W., T. Spann, and R. Rouse. 2011. Maintaining productivity in the presence of HLB. pp. 6-9, Citrus Industry. Southeast Agnet, Ocala, FL.

Schumann, A. W., T. Spann, K. Morgan. 2011. Update on Advanced Citrus Production Systems research, pp. 14-20, Citrus Industry. Southeast Agnet, Ocala, FL.

Spann, T. M., A. W. Schumann, R. Rouse, and R. Ebel. 2011. The foliar nutrition approach to managing Huanglongbing: Why it’s a viable option for Florida, pp. 6-10, Citrus Industry. Southeast Agnet, Ocala, FL. PDF

Zaman, Q. U., T. J. Esau, A. W. Schumann, D. C. Percival, Y. K. Chang, S. M. Read, and A. A. Farooque. 2011. Development of prototype automated variable rate sprayer for real-time spot-application of agrochemicals in wild blueberry fields. Computers and Electronics in Agriculture 76: 175-182. https://doi.org/10.1016/j.compag.2011.01.014

Farooque, A., Q. Zaman, A. Schumann, A. Madani, D. Percival, and T. J. Esau. 2010. Mapping soil moisture variability using electromagnetic induction methods, pp. 13. In ASABE [ed.], 9th International Drainage Symposium. ASABE, Quebec City, Ca.

Mann, K. K., A.W. Schumann and T.A. Obreza. 2010. Delineating productivity zones in a citrus grove using citrus production, tree growth and temporally stable soil data. Precision Agriculture 2010: 16. https://doi.org/10.1007/s11119-010-9189-y

Mann, K. K., A.W. Schumann, T.A. Obreza, and J.B. Sartain. 2010. Indicator Crop Bioassays to Define Citrus Productivity in Sandy Soils. HortScience 45: 1859-1865. https://doi.org/10.21273/HORTSCI.45.12.1859

Mann, K. K., A.W. Schumann, T.A. Obreza, W.G. Harris, and S. Shukla, and 2010. Spatial Variability of Soil Physical Properties affecting Florida Citrus Production. Soil Science 175: 487-499. https://doi.org/10.1097/SS.0b013e3181f79682

Melgar, J. C., A.W. Schumann and J.P. Syvertsen. 2010. Fertigation Frequency Affects Growth and Water and N Use Efficiencies of Swingle citrumelo Citrus Rootstock Seedlings. Hortscience 45: 1255-1259. https://doi.org/10.21273/HORTSCI.45.8.1255

Obreza, T. A., and A.W. Schumann. 2010. Keeping Water and Nutrients in the Florida Citrus Tree Root Zone. Horttechnology 20: 67-73. https://doi.org/10.21273/HORTTECH.20.1.67

Schumann, A. W. 2010. Precise Placement and Variable Rate Fertilizer Application Technologies for Horticultural Crops. Horttechnology 20: 34-40. https://doi.org/10.21273/HORTTECH.20.1.34

Schumann, A. W., H. K. Hostler, and S. D. Tumbo. 2010. What’s New in Variable Rate Technology?, pp. 4, Citrus Industry. Southeast Agnet, Ocala, FL. PDF

Schumann, A. W., H. K. Hostler, L. Waldo, and K. K. Mann. 2010. Update on Advanced Citrus Production System Research in Florida, pp. 6-11, Citrus Industry. Southeast Agnet, Ocala, FL.            

Schumann, A., T. Spann, T. Mann, T. Obreza, and M. Zekri. 2010. Effects of mineral nutrition on health and performance of citrus trees, pp. 22-24, Citrus Industry. Southeast Agnet, Ocala, FL.

Spann, T., and A. Schumann. 2010. Mineral Nutrition Contributes to Plant Disease and Pest Resistance. PDF

Spann, T., K. K. Mann, and A. W. Schumann. 2010. Citrus Tree Health and HLB Incidence, pp. 14-17, Citrus Industry. Southeast Agnet, Ocala, FL.

Swain, K. C., Q.U. Zaman, A.W. Schumann, D.C. Percival, D.D. Bochtis 2010. Computer Vision System for Wild Blueberry Fruit Yield Mapping. Biosystems Engineering 106: 389-394. https://doi.org/10.1016/j.biosystemseng.2010.05.001

Zaman, Q. U., A. W. Schumann, D. C. Percival, S. Read and T. J. Esau. 2010. Spot Application of pesticide using variable rate sprayer in wild blueberry, pp. 13. In ASABE [ed.], CIGR Section III ASABE, Quebec City, Ca.

Zaman, Q. U., A.W. Schumann and D.C. Percival. 2010. An Automated Cost-effective System for Real-time Slope Mapping in Commercial Wild Blueberry Fields. Horttechnology 20: 431-437. https://doi.org/10.21273/HORTTECH.20.2.431

Zaman, Q. U., K. Swain, A.W. Schumann, and D.C. Percival. 2010. Automated, low-cost yield mapping of wild blueberry. Applied Engineering in Agriculture 26: 225-232. https://doi.org/10.13031/2013.29540

Zhang, F., Q. U. Zaman, D. C. Percival, and A. W. Schumann. 2010. Detecting Bare Spots in Wild Blueberry Fields using Digital Color Photography. Applied Engineering in Agriculture 26: 723-728.  https://doi.org/10.13031/2013.34938           

Arshad, M., Q. U. Zaman, K. C. Swain, A. Madani, P. Havard, and A. W. Schumann. 2009. Electromagnetic induction methods for water management enhancement, pp. Paper No. 095580, 095588 pp., ASABE. American Society of Agricultural and Biological Engineers, St. Joseph, Michigan www.asabe.org, Reno, NV. https://doi.org/10.13031/2013.26920

Kim, D. G., T. F. Burks, A. W. Schumann, M. Zekri, X. Zhao, and J. Qin. 2009. Detection of Citrus Greening Using Microscopic Imaging. Agricultural Engineering International: the CIGR Ejournal XI: 17.

Noling, J. W., S. Buchanon, and A. W. Schumann. 2009. Impacts of EPA proposed buffer zone restrictions for use of soil fumigants on Florida strawberry acreage and production. Acta Horticulturae: 351-359. https://doi.org/10.17660/ActaHortic.2009.824.41

Schumann, A., K. Morgan, W. Castle, and J. Syvertsen. 2009. Advanced Citrus Production Systems in Florida, pp. 6, Citrus Industry. Southeast Agnet, Ocala, FL. https://www.researchgate.net/publication/

Schumann, A., M. Salyani, and R. Ehsani. 2009. Variable Rate Pesticide Application Technology, pp. 5, Citrus Industry. Southeast Agnet, Ocala, FL.

Spann, T., and A. Schumann. 2009. Greening Associated Nutrient Deficiency Syndrome, pp. 4, Citrus Industry. Southeast Agnet, Ocala, FL.

Swain, K. C., Q. U. Zaman, A. W. Schumann, and D. C. Percival. 2009. Detecting weeds and bare-spots in wild blueberry using ultrasonic technology, pp. 096879, ASABE. American Society of Agricultural and Biological Engineers, St. Joseph, Michigan www.asabe.org, Reno, NV.

Waldo, L. J., and A. W. Schumann. 2009. Spatial variability of soil water under citrus tree canopies in Central Florida. Acta Horticulturae: 147-154. https://doi.org/10.17660/ActaHortic.2009.824.16

Zaman, Q. U., A. W. Schumann, K. C. Swain, D. C. Percival, M. Arshad, and T. J. Esau. 2009. Evaluation of a cost-effective real-time slope sensing system for wild blueberry, pp. 221-227. In D. G. E.J. Henten, C. Lokhorst [ed.], 7th European Conference on Precision Agriculture 6-8-July 2009. Wageningen Academic Publishers, The Netherlands, Wageningen, Netherlands. https://doi.org/10.3920/978-90-8686-664-9

Zaman, Q. U., D. C. Percival, R. J. Gordon, and A. W. Schumann. 2009. Estimation of wild blueberry fruit yield using digital color photography. Acta Horticulturae: 57-65. https://doi.org/10.13031/2013.25302

Zaman, Q., F. Zhang, A. Schumann, and D. Percival. 2009. Bare Spots Mapping in Wild Blueberry Fields using Digital Photography, pp. 095582, ASABE. American Society of Agricultural and Biological Engineers, St. Joseph, Michigan www.asabe.org, Reno, NV. https://doi.org/10.13031/2013.26921        

Zhang, F., Q. Zaman, A. Schumann, D. Percival, D. Nams, and T. Esau. 2009. Detecting weeds in wild blueberry fields based on color images, pp. 96146, ASABE. American Society of Agricultural and Biological Engineers, St. Joseph, Michigan www.asabe.org, Reno, NV. https://doi.org/10.13031/2013.27065

Min, M., W. S. Lee, T. F. Burks, J. D. Jordan, A. W. Schumann, J. K. Schueller, and H. K. Xie. 2008. Design of a hyperspectral nitrogen sensing system for orange leaves. Computers and Electronics in Agriculture 63: 215-226. https://doi.org/10.1016/j.compag.2008.03.004

Obreza, T., M. Zekri, E. A. Hanlon, and A. Schumann. 2008. Leaf and soil sampling, testing and interpretation, pp. 4, Citrus Industry. Southeast Agnet, Ocala, FL.

Schumann, A. W., and E. A. Hanlon. 2008. Precision Agriculture for Citrus Nutrient Management, pp. 33-37. In T. A. Obreza and K. T. Morgan (eds.), Nutrition of Florida Citrus Trees, 2nd ed. Soil and Water Science Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL.

Schumann, A. W., and H. K. Hostler. 2008. Variable rate fertilization - getting started, pp. 4, Citrus Industry.

Schumann, A. W., and Q. U. Zaman. 2008. Quantifying Wild Blueberry Yield with Image Processing, pp. 1 pp., ASABE. ASABE, Providence, RI.

Schumann, A. W., and T. M. Spann. 2008. Irrigation controllers for citrus production, pp. 2, Citrus Industry.

Schumann, A. W., J. P. Syvertsen, and J. H. Graham. 2008. Microbial Soil Amendments do Little to Improve Citrus Tree Performance in Florida Soils, pp. 134-139, Proc. FSHS.

Schumann, A., and L. Waldo. 2008. Uncertainty of irrigation schedules triggered with soil water sensors in Florida citrus, pp. 1125-1125, Hortscience.

Schumann, A., W., and H. Hostler, K. 2008. Tips for fine-tuning variable rate fertilization, Citrus Industry.

Zaman, Q. U., A. W. Schumann, and D. C. Percival. 2008. Development of an Automated Slope Measurement and Mapping System, pp. 13 pp., ASABE. ASABE, Providence, RI. https://doi.org/10.13031/2013.25023

Zaman, Q. U., A. W. Schumann, D. C. Percival, and R. J. Gordon. 2008. Estimation of wild blueberry fruit yield using digital color photography. Transactions of the ASABE 51(5): 1539-1544. https://doi.org/10.13031/2013.25302

Cugati, S. A., W. M. Miller, J. K. Schueller, A. W. Schumann, S. M. Buchanon, and H. K. Hostler. 2007. Benchmarking the dynamic performance of two commercial variable-rate controllers and components. Transactions of the Asabe 50: 795-802. https://doi.org/10.13031/2013.23135

Schumann, A. W., H. K. Hostler, J. C. Melgar, and J. M. Syvertsen. 2007. Georeferenced Ground Photography of Citrus Orchards to Estimate Yield and Plant Stress for Variable Rate Technology, pp. 56-63. In, Proc. FSHS, 2007, Palm Beach, FL. ASHS.

Schumann, A., and K. Morgan. 2007. Controlled-release fertilizers reduce groundwater nitrate concentrations in citrus orchards. Hortscience 42: 862-863.

Zaman, Q. U., A. W. Schumann, and H. K. Hostler. 2007. Quantifying sources of error in ultrasonic measurements of citrus orchards. Applied Engineering in Agriculture 23: 449-453. https://doi.org/10.13031/2013.23479

Alva, A. K., S. Paramasivam, A. Fares, T. A. Obreza, and A. W. Schumann. 2006. Nitrogen best management practice for citrus trees II. Nitrogen fate, transport, and components of N budget. Scientia Horticulturae 109: 223-233. https://doi.org/10.1016/j.scienta.2006.04.011

Alva, A. K., S. Paramasivam, T. A. Obreza, and A. W. Schumann. 2006. Nitrogen best management practice for citrus trees - I. Fruit yield, quality, and leaf nutritional status. Scientia Horticulturae 107: 233-244. https://doi.org/10.1016/j.scienta.2005.05.017

Li, H., J. P. Syvertsen, C. W. McCoy, R. J. Stuart, and A. W. Schumann. 2006. Water stress and root injury from simulated flooding and Diaprepes abbreviatus root weevil larval feeding in citrus. Soil Science 171: 138-151. https://doi.org/10.1097/01.ss.0000187367.31094.e5

Nigg, H. N., R. A. Schumann, R. J. Stuart, E. Etxeberria, J. J. Yang, and S. Fraser. 2006. Consumption of sugars by Anastrepha suspensa (Diptera: Tephritidae). Annals of the Entomological Society of America 99: 1139-1145. https://doi.org/10.1603/0013-8746(2006)99[1139:COSBAS]2.0.CO;2

Schumann, A. W., K. Hostler, S. Buchanon, and Q. Zaman. 2006. Relating citrus canopy size and yield to precision fertilization. Proceedings of the 119th Annual Meeting of the Florida State Horticultural Society 119: 148-154.

Schumann, A. W., W. M. Miller, Q. U. Zaman, K. H. Hostler, S. Buchanon, and S. Cugati. 2006. Variable rate granular fertilization of citrus groves: Spreader performance with single-tree prescription zones. Applied Engineering in Agriculture 22: 19-24. https://doi.org/10.13031/2013.20183

Zaman, Q. U., A. Schumann, and H. K. Hostler. 2006. Rapid estimation of citrus tree damage from hurricanes in Florida using an ultrasonic tree measurement system. Horttechnology 16: 339-344.  https://doi.org/10.21273/HORTTECH.16.2.0339

Zaman, Q. U., A. W. Schumann, and H. K. Hostler. 2006. Estimation of citrus fruit yield using ultrasonically-sensed tree size. Applied Engineering in Agriculture 22: 39-43. https://doi.org/10.13031/2013.20186

Zaman, Q. U., and A. W. Schumann. 2006. Nutrient management zones for citrus based on variation in soil properties and tree performance. Precision Agriculture 7: 45-63. https://doi.org/10.1007/s11119-005-6789-z

Miller, W. M., A. Schumann, J. D. Whitney, and S. Buchanon. 2005. Variable rate applications of granular fertilizer for citrus test plots. Applied Engineering in Agriculture 21: 795-801. https://doi.org/10.13031/2013.19705

Schumann, A. W., and Q. U. Zaman. 2005. Software development for real-time ultrasonic mapping of tree canopy size. Computers and Electronics in Agriculture 47: 25-40. https://doi.org/10.1016/j.compag.2004.10.002

Zaman, Q. U., A. W. Schumann, and W. M. Miller. 2005. Variable rate nitrogen application in Florida citrus based on ultrasonically-sensed tree size. Applied Engineering in Agriculture 21: 331-335. https://doi.org/10.13031/2013.18448

Schumann, A. W., and M. E. Sumner. 2004. Formulation of environmentally sound waste mixtures for land application. Water Air and Soil Pollution 152: 195-217. https://doi.org/10.1023/B:WATE.0000015357.03531.b1

Schumann, A. W., and Q. U. Zaman. 2003. Mapping water table depth by electromagnetic induction. Applied Engineering in Agriculture 19: 675-688. https://doi.org/10.13031/2013.15663

Little, K. M., A. W. Schumann, and A. D. Noble. 2002. Performance of a Eucalyptus grandis x E-camaldulensis hybrid clone as influenced by a cowpea cover-crop. Forest Ecology and Management 168: 43-52. https://doi.org/10.1016/S0378-1127(01)00728-9

Schumann, A. W., and R. Munoz-Carpena. 2002. A simple, self-contained canal stage recorder. Applied Engineering in Agriculture 18: 691-696. https://doi.org/10.13031/2013.11324

Schumann, A. W., and M. E. Sumner. 2000. Chemical evaluation of nutrient supply from fly ash-biosolids mixtures. Soil Science Society of America Journal 64: 419-426. https://doi.org/10.2136/sssaj2000.641419x

Jackson, B. P., W. P. Miller, A. W. Schumann, and M. E. Sumner. 1999. Trace element solubility from land application of fly ash/organic waste mixtures. Journal of Environmental Quality 28: 639-647. https://doi.org/10.2134/jeq1999.00472425002800020030x

Schumann, A. W., and M. E. Sumner. 1999. Plant nutrient availability from mixtures of fly ashes and biosolids. Journal of Environmental Quality 28: 1651-1657. https://doi.org/10.2134/jeq1999.00472425002800050032x

Schumann, A. W., J. H. Meyer, and S. Nair. 1998. Evidence for different nitrogen use efficiencies of selected sugarcane varieties. Proceedings of the Seventy-Second Annual Congress of the South African Sugar Technologists' Association: 77-80. https://pdfs.semanticscholar.org

Schumann, A. W., and University of Georgia. 1997. Plant nutrient supply from fly ash-biosolid mixtures. Thesis (Ph D ), University of Georgia, 1997.

Schumann, A. W., Mills, H. A. 1996. Injury of leatherleaf fern and tomato from volatilized ammonia after fertilizer application. Journal of Plant Nutrition 19: 573-593. https://doi.org/10.1080/01904169609365144

Refereed Proceedings

Miller, W.M., A.W. Schumann,and J.D. Whitney. 2004. Evaluating variable rate granular fertilizer technologies in Florida citrus. Proceedings of the Florida State Horticultural Society 117:161-166.

Syvertsen, J.P., L.G. Albrigo, M.A. Ritenour, J.M. Dunlop, A.W. Schumann,R.C. Vachon, R.R. Pelosi, and M.S. Burton. 2004. Growth conditions affect sheepnosing in grapefruit. Proceedings of the Florida State Horticultural Society 117:350-354.

McCoy, C.W., W.S. Castle, J.H. Graham, J.P. Syvertsen, A.W. Schumann,and R.J. Stuart. 2004. Pesticide suppression of Diaprepes abbreviatus (L.) (Coleoptera: curculionidae) promoted differential growth and survival of ‘Hamlin’ orange trees budded to five rootstocks in a Phytophthora infested grove. Proceedings of the Florida State Horticultural Society 117:167-173.

Li, H., J.P. Syvertsen, C.W. McCoy, R.J. Stuart, and A.W. Schumann. 2004. Soil liming and flooding effects on Diaprepes root weevil larval survival and citrus seedling growth. Proceedings of the Florida State Horticultural Society 117:139-143.

Li, H., J.P. Syvertsen, C.W. McCoy, A.W. Schumann,and J.M. Dunlop. 2004. Soil redox potential and leaf stomatal conductance of two citrus rootstocks subjected to flooding and root weevil feeding. Proceedings of the Florida State Horticultural Society 117:252-256.

Non-Refereed Proceedings

Zaman, Q., A.W. Schumann, and H.K. Hostler. 2005. Quantifying sources of error in ultrasonic measurements of citrus orchards. ASAE Paper No. 051123. St. Joseph, Mich.: ASAE.

Li, H., J.P. Syvertsen, R.J. Stuart, C.W. McCoy, A.W. Schumann,and W.S. Castle. 2004. Soil magnesium, calcium and iron associated with root weevil distribution and citrus tree decline: A case study in Florida. Proceedings of the 10th Congress of the International Society of Citriculture, Agadir, Morocco (In Press).

Schumann, A.W. and Q. Zaman. 2004. Software for real-time ultrasonic mapping of tree canopy size. 7th International Conference on Precision Agriculture, July 2004. Paper No. 210. Minneapolis, Minn. 14 pp.

Schumann, A.W.,K.H. Hostler, W.M. Miller, and Q. Zaman. 2004. Sensor-based automatic yield monitoring for manually harvested citrus. American Society of Agricultural Engineers Annual International Meeting, August 2004. Paper No. 041098. St. Joseph, Mich.: ASAE. 13 pp.

Zaman, Q., A.W. Schumann,W.M. Miller, S. Buchanon, K. Hostler, and G. Perkins. 2004. Variable rate nitrogen application in Florida citrus based on ultrasonically-sensed tree size. 7th International Conference on Precision Agriculture, July 2004. Paper No. 213. Minneapolis, Minn. 13 pp.