Spectral radiometer to control variable-rate N applications for corn Peter Scharf, Eduardo Souza, and Ken Sudduth Department of Agronomy and Department of Biological Engineering, Univ. of Missouri and USDA Agricultural Research Service Objectives and relevance: ! We have already done four years of research showing that corn color measured with a spectral radiometer can do a good job of predicting how much N is needed at sidedress time or for mid-season rescue applications. ! Our ultimate objective is to mount the radiometer on a variable-rate applicator to make real-time variable-rate N applications based on corn color. ! This technology can potentially be extended to variable-rate N applications for other crops as well. ! The radiometer senses and corrects for variations in incoming sunlight due to time of day and clouds, but it appears that these corrections need improvement for the radiometer to be practical in the field. ! Our objective for this project is to improve the radiometer’s corrections for variations in incoming sunlight so that it will give the same color reading (and same recommendation) for the same plants regardless of time of day or cloud conditions. Procedures: ! Spectral radiometers will be mounted in a stationary position about ten inches above the canopy. ! Readings will be taken from morning until night over several days with a range of sky conditions (sunny, overcast, partly cloudy). ! Experiments will be done on corn ranging from knee-high to just before tasseling. ! Mathematical functions will be developed to compensate for the effects of changing sun angle and cloud conditions. ! A computer programmer will incorporate these functions into programs for translating radiometer readings into variable-rate N recommendations. ! These programs will ultimately be used in developing real-time control of variable-rate N applicators based on corn color measured with a spectral radiometer. ! We will also continue separately-funded experiments in which we collect GPS (global positioning system)-referenced radiometer readings in field-scale on-farm N rate experiments (three experiments in Missouri and three in Iowa). Current status and importance of research area: ! Field-scale research has shown that corn N need often varies by 100 lb N/acre or more within a field (Malzer et al., 1996; Blackmer and White, 1998). ! Nitrogen-deficient corn is lighter in color than nitrogen-sufficient corn, and color measurements can be used to predict N need (Piekielek and Fox, 1992). ! Color has been mainly measured with a hand-held instrument in the past, which has limited its usefulness for N management in production fields; measurement on the go with an instrument on board a variable-rate applicator would make this idea much more
practical.
! A German company, Hydro, has already introduced a variable-rate N applicator for ! ! ! !
wheat based on this concept. However, reports from Kentucky, where one has been imported, are not favorable, nor is this applicator suited for use on corn. Our research group appears to be in the lead nationally in terms of hard data that can be used to translate radiometer measurements into N rate recommendations. Ten on-farm experiments in Missouri showed that corn color measured with a radiometer was related to optimum sidedress N rate (Figure 1). A radiometer could also be used to direct high-clearance rescue N applications when substantial N is lost during a wet May/June, as happened in northeast Missouri in 1998 (Figure 2). This technology could become very important for maintaining productivity if N fertilizer
Optimum sidedress N rate
250 200 150 100 50 0 0.9
1.1
1.3
1.5
1.7
Green/near infrared relative to high-N plots at V6
comes under regulation, because it allows precise application according to crop needs.
Figure 1. Corn color measured with a spectral radiometer can predict optimum sidedress N rate for on-farm experiments in Missouri.
Figure 2. Nitrogen deficiency was widespread over northeast Missouri in 1998 due to wet soil conditions in June leading to denitrification.
Timetable for proposed research: April-June 2001 Plant corn at Bradford Farm near Columbia over a wide range of planting dates, so that we will have corn at a variety of stages at any given time. June-August 2001
Take radiometer readings on corn from morning till night with a variety of sky conditions and corn growth stages.
Sept.-Nov. 2001
Analyze data and develop mathematical functions to correct for sun angle and sky/cloud conditions.
December 2001
Incorporate correction functions into a computer program that
translates radiometer readings into N rate recommendations. January 2002 Final report Strategy for application of knowledge: We hope to partner with, or otherwise make the information that we generate, available to industry so that this technology can be commercialized in a way that will result in consistent and reliable N rate recommendations and applications. We are in contact with three companies with an interest in developing this technology for market: AGCO, Patchen, a former John Deere subsidiary based in California that manufactures weed vision/spraying systems, and Crop Circle, a startup manufacturer of spectral radiometers for agricultural use. We have had several discussions with Dave Murray of AGCO about the possibility of high-clearance variable-rate radiometer-directed N applications. References: Blackmer, A.M. and S.E. White. 1998. Using precision farming technologies to improve management of soil and fertilizer nitrogen. Aust. J. Agric. Res. 49:555-564. Malzer, G.L., P.J. Copeland, J.G. Davis, J.A. Lamb, P.C. Robert, and T.W. Bruulsema. 1996. Spatial variability of profitability in site-specific N management. p. 967-975. In P.C. Robert et al. (ed.) Precision Agriculture, Proceedings of the Third International Conference. American Society of Agronomy, Madison, WI. Piekielek, W.P. and R.H. Fox. 1992. Use of a chlorophyll meter to predict sidedress nitrogen requirements for maize. Agron. J. 84:59-65. Budget: ! The budget will be primarily for the salary of Eduardo Souza, a visiting professor of Agricultural Engineering from Brazil, who will conduct the experiments. ! Eduardo has been a visiting scientist at the University of Missouri since the summer of 2000. " He has done considerable background research on the problems of sun angle and cloud cover effects on reflectance values measured by a spectral radiometer. " His support from his home institution runs out in June 2001. In order to keep him here through the field season to bring this project to completion, we propose six months’ salary at $3500/month for a total of $21,000. ! We also propose four weeks of computer programmer time at $25/hour, for a total of (4 weeks) x (40 hours/week) x ($25/hour) = $4,000. ! We have most of the equipment that we will need for the experiments (two different models of spectral radiometer, laptop computers, cables) but propose a budget of $1000 to be used for miscellaneous additional equipment needs such as fabrication of radiometer stands, replacement filters for radiometers, etc. Budget summary: Salary, visiting scientist 100% time for 6 months Programmer contract time
$21,000 4,000
Miscellaneous equipment Total
1,000 $26,000
Peter Clifton Scharf Professional Interests
! developing, evaluating, and promoting tools to predict crop N needs, including variable-rate N management based on remote sensing or in-field radiometry ! minimizing environmental impacts of agricultural nutrients ! optimizing crop management; economic comparisons of production alternatives Qualifications Ability to communicate effectively, to cooperate with others, and to manage projects and people Good knowledge of scientific literature, current research programs, and current practices in the area of nutrient management Outstanding laboratory, field, project design, and data analysis skills Excellent natural science background including soil science, physiology, genetics & breeding, chemistry, physics, microbiology, biochemistry, and ecology Education Degree Ph.D. M.S.
Date May 1993 July 1988
Institution Virginia Tech Virginia Tech
Major Agronomy Agronomy
B.S.
August 1982
University of Wisconsin
Biochemistry, Genetics
Professional Experience 1995 to present Assistant Professor in the Agronomy Department of the University of Missouri. This is a tenure-track position in the area of nutrient management. Program emphasis is on improving nitrogen fertilizer efficiency: ! development, assessment, and dissemination of tools (including remote sensing and in-field radiometry) for matching N fertilizer rates with actual crop needs in corn and wheat ! nitrogen management to minimize losses Other projects that I am working on or pursuing include: ! starter fertilizer for no-till corn and soybean ! P and K response of grain crops on different soils ! a subsoil P & K fertility map for Missouri ! soil pH effects on herbicide carryover in no-till and across landscapes ! P and K behavior in soils, soil-specific fertilization
! phosphorus runoff from cropland ! development of GIS-based software for whole-farm nutrient mgmt. planning 1993 to 1995 Post-doctoral Microbiologist in the Soil-Plant-Nutrient Research Unit of USDA-ARS located in Fort Collins, Colorado. Research on asymbiotic N fixation linked to cellulose degradation. 1988 to 1993 Graduate Project Assistant and Research Associate in the Department of Crop and Soil Environmental Sciences, Virginia Polytechnic Institute and State University. Developed field-specific nitrogen rate recommendations for winter wheat. Awards Year 1994
Award Sigma Xi Dissertation Award, VPI&SU chapter
1992 1987
Obenshain Scholarship, VPI&SU Dept. of Crop & Soil Environmental Sciences Potash and Phosphate Institute Fellowship
1986
National Science Foundation Fellowship
1982
Graduated from U. of Wisconsin honors program with highest distinc-
1981
tion Henry Steenbock Fellowship, University of Wisconsin College of Agriculture and Life Sciences
1980
National Science Foundation Undergraduate Research Participation Award
1979,80,81 M.S. Peterson Scholarship, U. of Wisconsin Dept. of Biochemistry Publications Scharf, Peter C. and John A. Lory. 2001. Calibrating corn color from aerial photographs to predict sidedress N need. Submitted to Agron. J. Scharf, Peter C. 2001. Soil and plant tests to predict optimum N rates for corn. J. Plant Nutr. (in press). Scharf, Peter C., David B. Quarles, and John A. Lory. 2000. Nitrogen response of no-till corn in the first and second years following Conservation Reserve Program. Comm. Soil Sci. Plant Anal. 31:2501-2508. Scharf, Peter C. 1999. On-farm starter fertilizer response in no-till corn. J. Prod. Agric. 12:692-695. Scharf, Peter C. and M.M. Alley. 1995. Nitrogen loss inhibitors evaluated for humid region wheat production. J. Prod. Agric. 8:163-164, 269-275.
Scharf, Peter C. and M.M. Alley. 1994. Residual soil nitrogen in humid region wheat production. J. Prod. Agric. 7:15-16, 81-85. Scharf, Peter C., Marcus M. Alley, and Yong Zhen Lei. 1993. Spring nitrogen on winter wheat: I. Farmer-field validation of tissue test-based rate recommendations. Agron. J. 85:1181-1186, erratum Agron. J. 86(1):iv.
VITAE
EDUARDO GODOY DE SOUZA • • • •
Born January 10, 1958, in Brazil. Married; three children. Home address: 1021 Southpark Dr. Apt.4. Columbia, MO 65201 U.S.A.
POSITION AND PROFESSIONAL ADDRESS:
Visiting Associate Professor at the University of Missouri-Columbia. 257 Agricultural Engineering Bldg. Columbia, MO 65211 U.S.A. Email:
[email protected]
EDUCATION •
Post-Dr, 1995.
•
PhD, Mechanical 1989.
•
MS, Mechanical Engineering, UNICAMP, BR. 1987.
•
Specialization, Agricultural Development, Germany. 1983.
•
BS, Mechanical Engineer, State University of São Paulo (USP), BR. 1981.
Agricultural
Engineering,
Engineering,
State
University
of
University
Engineering,
German
Nebraska
of
-
Campinas
Institution
Lincoln,
USA.
(UNICAMP),
BR.
to
International
Areas of Expertise •
Precision agriculture, remote sensing, spatial variability, geoestatistics.
PROFISSIONAL EXPERIENCE •
Adjunct professor of the Dept. of Agricultural Engineering Universidade Estadual do Oeste do Paraná, UNIOESTE, Brazil, since 1992.
•
Director of the Technological Innovations Center of the UNIOESTE.
•
Coordinator of the Master in Agricultural Engineering.
of the February
PARTICIPATION IN INTERNATIONAL MEETINGS, presenting technical papers 1987 ASAE International Winter Meeting. "Indirect Evaluation of Diesel Engines". St.Joseph, USA. December 1987. ( ASAE PAPER 87-1505 )
the
Torque
of
1988 ASAE International Winter Meeting. "Efficiency and Economical Diesel Engines". St.Joseph, USA. December 1988. ( ASAE PAPER 88-1556 ) 1988 ASAE International Winter Meeting. "Prediction of Tractor Concrete". St.Joseph, USA. December 1988. ( ASAE PAPER 88-1514 ) 1990 ASAE International Winter Meeting. "Overall Efficiency Concrete". Chicago, USA. December 1990. ( ASAE PAPER 90-1574 ).
of
Performance
on
of
1991 ASAE International Winter Meeting. "Ballast Optimization of Assist Tractor". Chicago, USA. December 1990. ( ASAE PAPER 91-1593 ). 1992 ASAE International Winter Meeting. "Overall Efficiency Field". Chicago, USA. December 1990. ( ASAE PAPER 92-1517 ). 1996 ASAE Annual International Meeting. "Optimum Working Engines". Phoenix, USA. July 1996. ( ASAE PAPER 96-1100 ).
Analysis
Tractors
a
Front
of
Wheel
Tractors
Curve
for
on
in
Diesel
1998 ASAE Annual International Meeting. "SERMIA- Software for Rational Selection of Machines and Agricultural Implements ". Orlando, USA. July 1998. ( ASAE PAPER 98-5042 ). 1998 ASAE Annual International Meeting. "EPM-Software Mapping". Orlando, USA. July 1998. ( ASAE PAPER 98-5043 ).
for
Engine
Performance
PUBLICATIONS
MEINERS, H.H. and SOUZA, E.G. Schlepper- made 22. April 1987. Germany.
in
Brazil.
LANDTECHNICK
42(4):
20-
SOUZA, E.G. and MILANEZ, L.F. Indirect Evaluation of the Torque of Diesel Engines. Transactions of the ASAE 31(5): 1350-1354. September-October 1988.USA. SOUZA, E.G. and MILANEZ, L.F. Efficiency and Economical Analysis of Diesel Engines. Transactions of the ASAE 33(1): 8-14. January-February 1990.USA. SOUZA, E.G. and MILANEZ, L.F. Prediction of Tractor Transactions of the ASAE 34(3): 727-732. May-June 1991.USA.
Performance
SOUZA, E.G. and MILANEZ, L.F. Overall Efficiency of Tractors Transactions of the ASAE 34(6): 2333-2339. November-December 1991.USA.
on
Concrete.
on
Concrete.
SOUZA, E.G. and MILANEZ, L.F. Overall Efficiency of a Tractor in Engineering in Agriculture 10(6): 771-775. November-December 1994. USA.
Field.
SOUZA, E.G.; PINHO, N.; MILANEZ, L.F. Ballast Optimization of Assist Tractor. Agricultural Mechanization in Asia, Africa and 26(1): 13-16. Winter 1995. USA.
a Front Wheel Latin America.
SOUZA, E.G. and SANTA CATARINA, A. Optimum Working Curve Transactions of the ASAE 42(3): 559-563. May-June 1999.USA.
for
Diesel
Applied
Engines.
SOUZA, E.G.; JOHANN, J.A.; ROCHA, J.V.; RIBEIRO, S.R.A.; SILVA, M.S.; URIBEOPAZO, M.A.; MOLIN, J.P.; OLIVEIRA, E.F.; NÓBREGA, L.H.P. Spatial Variability of Soil Chemistry Attributes. Submitted for publication in the Brazilian Society of Agricultural Engineering. 1999. Brazil.
KENNETH A. SUDDUTH Agricultural Engineer Cropping Systems and Water Quality Research Unit USDA Agricultural Research Service 269 Agricultural Engineering Bldg., U. of Missouri Columbia, MO 65211 573.882.4090 fax 573.882.1115
[email protected] Employment 1989 - present
1985 - 1989
1981 - 1985
USDA Agricultural Research Service, Columbia, MO. Agricultural Engineer, Cropping Systems and Water Quality Research Unit. Leader of a multidisciplinary team conducting precision agriculture research. Engineering research focuses on sensors, instrumentation, and data management and interpretation, including sensing of soil properties and grain yield, variable rate chemical application, and development of data analysis techniques. Cooperative research includes field-scale implementation of precision agriculture systems and evaluation of economic and environmental effects of precision agriculture. Also Adjunct Assistant Professor, Biological and Agricultural Engineering Department, University of Missouri. USDA Agricultural Research Service, Urbana, IL. Agricultural Engineer, Crop Protection Research Unit. Research on sensors and instrumentation applied to crop production. Developed and patented a near-infrared soil organic matter sensor; developed propulsion, data acquisition, and automated cone penetrometer systems for a wide-frame instrumentation carrier. John Deere Product Engineering Center, Waterloo, IA. Engineer, Hydraulic Systems Design and Analysis.
Education Ph.D.
M.S. B.S.
Agricultural Engineering, University of Illinois, Urbana, IL, 1989. Specialization in sensors and controls for crop production systems. Dissertation: Near infrared reflectance soil organic matter sensor. Agricultural Engineering, University of Missouri, Columbia, MO, 1981. Specialization in soil and water conservation. Thesis: Terrace location by computer. Dual degree in Agriculture and Agricultural Engineering (honors scholar), University of Missouri, Columbia, MO, 1979.
Professional Honors and Awards
C 1995 Young Member of the Year Award, Missouri Section of ASAE and 1996 Young Member of the Year Award, Mid-Central Conference of ASAE C USDA Invention Award and Federal Inventor’s Incentive Award for U.S. Patent 5,038,040. C Member of Alpha Epsilon, Tau Beta Pi, Alpha Zeta, Gamma Sigma Delta, Phi Kappa Phi, and Sigma Xi Honor Societies. Publications Sudduth, K.A. and J.W. Hummel. 1993. Portable near infrared spectrophotometer for rapid soil analysis. Transactions of the American Society of Agricultural Engineers. 36(1): 187-195. Sudduth, K.A. and J.W. Hummel. 1993. Soil organic matter and moisture measurements with a portable near infrared spectrophotometer. Transactions of the American Society of Agricultural Engineers 36(6): 1571-1582. Doolittle, J.A., K.A. Sudduth, N.R. Kitchen, and S.J. Indorante. 1994. Estimating depths to claypans using electromagnetic induction methods. Journal of Soil and Water Conservation 49(6): 572-575. Drummond, S.T., S.J. Birrell, and K.A. Sudduth. 1995. Bidirectional serial-to-parallel converter for data acquisition and control. Transactions of the American Society of Agricultural Engineers 38(6):1939-1941. Sudduth, K.A., S.C. Borgelt, and J. Hou. 1995. Performance of a chemical injection sprayer system. Applied Engineering in Agriculture 11(3):343-348. Birrell, S.J., K.A. Sudduth, and S.C. Borgelt.1996. Comparison of sensors and techniques for crop yield mapping. Computers and Electronics in Agriculture 14:215-233. Borgelt, S.C., J.D. Harrison, K.A. Sudduth, and S.J. Birrell. 1996. Evaluation of GPS for applications in precision agriculture. Applied Engineering in Agriculture 12(6): 633-638. Hummel, J.W., L.D. Gaultney, and K.A. Sudduth. 1996. Soil property sensing for site-specific crop management. Computers and Electronics in Agriculture 14:121-136. Kitchen, N.R., K.A. Sudduth, and S.T. Drummond. 1996. Mapping of sand deposition from 1993 Midwest floods with electromagnetic induction measurements. Journal of Soil and Water Conservation 51(4):336-340. Sudduth, K.A. and J.W. Hummel. 1996. Geographic operating range evaluation of a NIR soil sensor. Transactions of the American Society of Agricultural Engineers 39(5): 1599-1604. Borgelt, S.C., R.E. Wieda, and K.A. Sudduth. 1997. Geostatistical analysis of soil chemical properties from nested grids. Applied Engineering in Agriculture 13(4): 477-483.
