Progress 09/15/00 to 09/14/05
Outputs
This has been a multi-disciplinary, multi-agency, multi-location, and multi-year project. The project has now been completed by all the participating individuals (PI, Co-PI, Collaborators and Cooperators, 18 CSU and USDA-ARS scientists, extension specialists, and graduate students). The multidisciplinary aspects investigated in this project were: Nutrient Management, Insect, Disease, and Weed Management, Irrigation management, Remote Sensing, Economics, and Extension/Outreach program. Significant findings from the final year 2005 and previous years of work that addresses the nature of this project are reported here. This project had focused primarily in development of unique techniques of delineating management zones. Management zones were formally introduced as a means to manage in-field spatial variability nearly a decade ago. Several methods of management zone delineation have been proposed and researched throughout the United States and elsewhere. Overall, the
results have been variable. However, in the Western Great Plains region of the United States, among the four techniques that were studied in this project, management zone technique based on bare-soil color have been shown to be the most promising. To assess the performance of management zones research sites were located on several large-scale production irrigated maize fields in Eastern Colorado. Fields were divided into management zones based on bare-soil color. Fields were managed using both traditional uniform N application and a management zones approach. Several parameters were measured and compared between management including: grain yield, biomass, N uptake, N-use efficiency, soil texture, soil organic matter, soil bulk density, and economic returns. Management zones based on bare-soil were found to be significantly different with regard to soil physical properties (soil texture, bulk density, and organic matter). Grain yields and N uptake from irrigated maize fields were also
found to be consistently different between management zones. When comparisons were made between traditional uniform N applications and variable N applications based on soil-color based management zones, the variable N application based on site-specific management zones were found to be more economically efficient than the uniform N application strategies. Overall, research conducted over the last five years indicates that bare-soil management zones are an effective and viable means of managing in-field spatial variability in an environmentally sustainable and agronomically profitable manner.
Impacts
The impact of managing fields using soil color based management zones in irrigated corn production system is huge. Based on current prices of nitrogen alone, our study indicated that farmers would have an advantage of 12 to 32 dollars per acre in net return compared to traditional uniform application of nitrogen. Such a finding could potentially translate into millions of dollars of potential revenue for Colorados agriculture.
Publications
- Khosla, R., Inman, D., and Westfall, D.G. 2005. Book Chapter: Optimum N management Using Site Specific Management Zones. In Precision Agriculture. J. Stafford (ed) Wageningen Academic Publishers. 827 pp.The Netherlands.
- Inman, D., Khosla, R., Lefsky, M., and Westfall, D.G. 2005. Book Chapter: Early Season Grain Yield Prediction Using Site-Specific Management Zones and remote Sensing. In Precision Agriculture. J. Stafford (ed) Wageningen Academic Publishers. 835 pp. The Netherlands.
- Mzuku, M., Khosla, R., Reich, D., Inman, D., Smith, D., and MacDonald, L. 2005. Spatial Variability of Measured Soil Properties Across Site Specific Management Zones. Soil Sci. Soc. Am. J. 69: 1572-1579.
- Inman, D., Khosla, R., and Mayfield, T. 2005. On-the-go active remote sensing for efficient crop nitrogen management. Sensor Review. 25: (3) 209-214.
- Inman, D., Khosla, R., Westfall, D.G., and Reich, R. 2005. Nitrogen Uptake across Site-Specific Management Zones in Irrigated Corn Production Systems. Agron. J. 97:169-176.
- Berry, J.K, Delgado, J.A., Pierce, F.J., and Khosla, R. 2005. Applying Spatial Analysis for Precision Conservation Across the Landscape. J. of Soil & Water. 60: 363-370.
- Delgado, J., Khosla, R., Westfall, D.G., Bausch, W., and Inman, D. 2005. Nitrogen Fertilizer Management Based on Site-Specific Management Zones Reduces Potential for NO3-N Leaching. J. of Soil & Water. 60: 402-410.
- R. Khosla, Inman, D., Westfall, D.G., and Reich, R. 2005. Spatial Distribution of Plant Nitrogen Uptake Across Site-Specific Management Zones. In the proceedings of the Western Nutrient Management Conference, pgs 135-140. Potash & Phosphate Institute, Brookings SD.
- Mzuku, M., Khosla, R., Inman, D., Reich, R., and Westfall, D. 2005. Spatial and Temporal Variability of Measured Soil Properties Across Site-Specific Management Zones. ASA-CSSA-SSSA International Annual Meetings Abstracts. [CD-ROM] ASA, Madison, WI.
- Van Wychen, S., Khosla, R., Delgado, J., and Reich, R. 2005. Nitrates in Soil and Plant Systems Across Site-Specific Management Zones. ASA-CSSA-SSSA International Annual Meetings Abstracts. [CD-ROM] ASA, Madison, WI.
- Van Wychen, S., and Khosla, R. 2005. Quantifying Nitrate Leaching Below Root Zone Across Site Specific Management Zones. SWCS International Meetings Abstract. [CD-ROM] Ankeny, IA.
- Inman, D., Khosla, R., Lefsky, M., and Westfall, D.G. 2005. Book Chapter: Early Season Grain Yield Prediction Using Site-Specific Management Zones and remote Sensing. ECPA and ECPLF International Meetings Program book [CD-ROM] Wageningen Academic Publishers, The Netherlands.
- Hansen, N.C., Ward, S., Khosla, R., and Fenwick, J. 2005. A National Look at Undergraduate Programs in Agronomy and Soil Science. ASA-CSSA-SSSA International Annual Meetings Abstracts. [CD-ROM] ASA, Madison, WI.
- Khosla, R., Inman, D., and Westfall, D.G. 2005. Optimum N management Using Site Specific Management Zones. ECPA and ECPLF International Meetings Program book [CD-ROM] Wageningen Academic Publishers, The Netherlands.
|
Progress 01/01/04 to 12/31/04
Outputs
This is a multi-disciplinary, multi-agency, multi-location, and multi-year project. Progress is being made by all the participating individuals (18 CSU and USDA-ARS scientists, extension specialists, and graduate students) in this project. The multidisciplinary aspect includes: Nutrient Management, Insect, Disease, and Weed Management, Irrigation management, Remote Sensing, Economics, and Extension/Outreach program. Significant findings from the year 2004 work that addresses the nature of this project are reported here. Nutrient Management: One aspect of the production-level management zone approach to N management that has not been thoroughly researched is the determination of the production potential of each zone. Existing N algorithms are based on field average correlations, their use can lead to over and under application of N fertilizer. The objective of this study was to determine the productivity potential of site-specific management zones in order to optimize
within-zone N fertilizer recommendations. This study was conducted on two irrigated cornfields in northeastern Colorado. Fields were classified into high, medium, and low-productivity potential management zones. A completely randomized block design was used. Treatments consisted of four N application rates and a control. Results from this study show that differential productivity potential exists between production level management zones. N application algorithms that include indicator variables for production potential could be used to improve N recommendation for sites managed using the production level management zone approach. In-season Passive Remote Sensing: Two N management schemes (producer traditional practice vs. `as needed by the crop' based on remote sensing of crop N status) were compared for four site years to determine the potential for reducing applied N and its effect on grain yield. The study was conducted in commercial center-pivot irrigated cornfields. Wedges were
established in selected areas to facilitate fertigation with the center pivot sprinkler. The wedge areas were fertigated based on plant N sufficiency using the N Reflectance Index calculated from green and near-infrared canopy reflectance. The remainder of the field was fertigated at the producer's discretion based on traditional practice. In all cases, the remote sensed in-season N management areas had less N applied (39 to 166 kg N ha-1) without reducing grain yield. In another study, high-resolution satellite data were compared to ground-based multispectral data to determine if QuickBird satellite data could provide information on a crop's N status equivalent to a ground-based system using Exotech radiometers. Same day data acquisition occurred three times which corresponded to the V10, V12, and V15 corn growth stages. Results from the three clear days of the five attempts to acquire satellite images suggest that QuickBird data can detect corn N deficiencies comparable to the
ground-based system; however, cloud cover over the area of interest is a hindrance to satellite data acquisition.
Impacts
The development and adoption of productivity level management zone systems to better manage the inherent variability of farm fields is more profitable compared to conventional management approaches. Management zones approach will reduce over and under application environmentally sensitive ag-chemical applications, maintain or increase grain yield, increase net profit, and enhance efficiency of agricultural inputs.
Publications
- Gent, D., H.F. Schwartz, and R. Khosla. 2004. Managing Iris yellow spot virus of Onion with cultural Practices, Resistant Cultivars, and Novel Chemical Treatments. In Proceedings of the Annual Meeting of American Phyto-pathological Society, July 31- August 4, Anaheim, CA.
- O'Meara, S., Westra, P., and R. Khosla. 2004. Evaluation of the Spatial Dynamics of Weeds in Irrigated Corn. In Proceedings of the Annual meetings of the Western Society of Weed Sciences. Colorado Springs, CO Mar 9-11, pp26.
- Hornung, A. 2004. Evaluation of Site-Specific management Zones In Irrigated Maize (Zea mays L.): Grain Yield, Biomass, and Nitrogen Use Efficiency. M.S. Degree Thesis. Colorado State University, Fort Collins, CO.
- Berry, J.K., J.A. Delgado, W. Bausch, F.J. Pierce, and R. Khosla. 2004. Precision Conservation Across the Landscape: Applying Spatial Analysis from Site Specific to Regional Contexts. In Abstracts of the Annual meetings of the American Society of Agronomy, October 30-Nov 4th, Seattle, WA.
- Delgado. J., and R. Khosla. 2004. Assessment of potential use of precision conservation for groundwater quality. In the proceeding of the 59th Annual Meetings of Soil & Water Conservation Society, St. Paul, MN, July 24-28th.
- Delgado, J., W. Bausch, R. Khosla, and D. Westfall. 2004. Precision Conservation for Irrigated Systems. In Abstracts of the Annual meetings of the American Society of Agronomy, October 30-Nov 4th, Seattle, WA.
- Schwartz, H. F., Gent, D. H., and Khosla, R. A thrips-transmitted virus threatens the United States onion industry. Proc. of the Infectious Diseases Colloquium, April 5-6, 2004, Fort Collins, CO.
- Fichtner, S. M., Gent, D. H., Schwartz, H. F., Cranshaw, W. S., Mahaffey, L., and Khosla, R. Geospatial relationships of Iris yellow spot virus and thrips to onion production in Colorado. Proc. of the 2004 National Allium Research Conference, Dec. 8-10, 2004, Grand Junction, CO.
- Koch, B., R. Khosla, D.G. Westfall, M. Frasier, and D. Inman 2004. Economic feasibility of variable rate N application in irrigated corn. Agron. J. 96:1572-1580.
- Inman, D., R. Khosla, D.G. Westfall, and R. Reich. 2004. Nitrogen uptake across site-specific management zones in irrigated corn production systems. Agron. J. 97:169-176.
- Gent, D., H. Schwartz, and R. Khosla. 2004. Distribution and incidence of iris yellow spot virus in Colorado and its relation to onion plant populations and yield. J. of Plant Diseases. 88 (5) 446-452.
- Ceplecha, Z.L., R.M. Waskom, T.A. Bauder, J.L. Sharkoff and R. Khosla. 2004. Vulnerability assessments of Colorado ground water to nitrate contamination. J. Water, Air, and Soil Pollution 159 (1): 373-394.
- Bausch, W., K. Diker, R. Khosla, and J. F. Paris. 2004. Estimating corn nitrogen status using ground-based and satellite multispectral data. In Proceedings of the 49th Annual Conference of the International Society for Optical Engineering, Denver, CO. Aug 2-6. CD-ROM
- Khosla, R., D. Inman, and D.G. Westfall. 2004. Determining productivity potential of site-specific management zones for optimum N management. In the Proceedings of the 7th International Precision Agriculture Meeting, July 25-28th, 2004, Minneapolis, MN. CD-ROM.
- Bausch, W.C., K. Diker, J.F. Paris, and R. Khosla. 2004. Estimating plant nitrogen status in irrigated corn using ground-based and satellite data. In the Proceedings of the 7th International Precision Agriculture Meeting, July 25-28th, 2004, Minneapolis, MN. CD-ROM.
- Khosla, R, D.G. Westfall, W. Gangloff, and D. Inman. 2004. Characterizing in-field spatial variability using site-specific management zones for efficient crop production systems. In Proceedings of Global Monitoring Science and Technology Conference, Denver, CO. Sept. 20-24th.
- Gangloff, W.J., R. Reich, D.G. Westfall, and R. Khosla. 2004. Delineation of Soil Productivity Management Zones: Yield Response. In Abstracts of the Annual meetings of the American Society of Agronomy, Seattle, WA. Oct. 30-Nov 4th.
- Gangloff, W.J., D. G. Westfall, R. Khosla, and R. Reich. 2004. Areal association of production level management zone delineation and yield classes. In the Proceedings of the 7th International Precision Agriculture Meeting, July 25-28th, 2004, Minneapolis, MN. CD-ROM.
- Khosla, R., B. Koch., D.G. Westfall, and M. Frasier. 2004. Economics of variable rate N management on corn. In Proceedings of the 2004 Great Plains Soil Fertility Conference, Denver, CO. March 2nd & 3rd. pg 92-97.
- Gangloff, W.J., D.G. Westfall, R. Khosla, T. Shaver, and H. Farahani. 2004. Developing, delineating, and managing production level nutrient management zones. In Proceedings of the 2004 Great Plains Soil Fertility Conference, Denver, CO. March 2nd & 3rd. pg 53-58.
- Khosla, R., and D.G. Westfall. 2004. It Pays to Manage Nitrogen Using Precision Agriculture Techniques. Extension Newsletter From the Ground Up Agronomy News on Nitrogen Fertilizer. April 2004. Vol 24, Issue 1, pg 5-6.
- Waskom, R., and R. Khosla. 2004. Nitrogen Application: What, When, Where and How to apply Nitrogen Matters. CSU Cooperative Extension Newsletter From the Ground Up Agronomy News on Nitrogen Fertilizer. April 2004. Vol 24 Issue 1. pg 12-13.
- Khosla. R. 2004. Variable Rate technology: Does it work? In Proceedings of the 16th Annual High Plains No-Till Conference Feb. 4-5, 2004, Greeley, CO. pg M1-M6.
- Khosla, R. 2004: Understanding iPAQ AgGPS Mapping and Scouting Program. Training Manual for hands-on training for extension educators, crop consultants and growers. 73 pages.
- Khosla, R. 2004. Understanding ArcGIS: A comprehensive tool for Agricultural data base management. Manual for hands-on training for extension educators, crop consultants and growers. 163 pages.
- Khosla, R., A. Sampath, and J. Fenwick. 2004. Comprehensive 3-dimensional Interactive and Animated Educational Audio-Visuals on Precision Agriculture. Twenty-four (24) CD-ROM based 3-D animated modules have been developed. These animations demonstrate complex principles of Global Positioning System and Geographic Information Systems and how are they being used in Agriculture. CD-ROM.
- Khosla, R. A. Sampath, and J. Fenwick. 2004. Interactive and Educational Online Modules on Precision Agriculture. In Abstracts of the Annual meetings of the American Society of Agronomy, Seattle, WA. October 30-Nov 4th.
- Khosla, R. 2004. Educating Extension Agents to Use Handheld Differential GPS Units. In Abstracts of the Annual meetings of the American Society of Agronomy, Seattle, WA. October 30-Nov 4th.
|
Progress 01/01/03 to 12/31/03
Outputs
This is a multi-disciplinary, multi-agency, multi-location, and multi-year project. Progress is being made by all the participating individuals (18 CSU and USDA-ARS scientists, extension specialists, and graduate students) in this project. The multidisciplinary aspect includes: Nutrient Management, Insect, Disease, and Weed Management, Irrigation management, Remote Sensing, Economics, and Extension/Outreach program. Significant findings from the 2003 work are reported here. Insect Management: The temporal and spatial variability observed in pest insect distributions has been one of the major challenges for insect pest managers. Sampling costs have limited the compatibility of insect pest management and precision agriculture. Given that the cost of obtaining an adequate sample for an entire field is often prohibitive, the affordability of sampling smaller units as required by grid sampling approaches would be even lower. For these reasons, our research is focusing on
relating insect pests of corn to production potential management zones. Such zones are defined as areas within a field that share similar yield limiting characteristics. If insect damage is proven to correspond to management zones, insect treatments could be targeted towards specific management zones instead of the whole field, thus reducing the amount of insecticides used and saving the grower money. Our study found that: (i) Western corn rootworm larvae and adults were more common in high productivity management zones than in low productivity management zones (ii) European corn borer larvae were more prevalent in the high productivity management zone in the most heavily infested field. (iii) Western bean cutworm egg masses were evenly distributed among management zones at one field, but at this same field larvae were most common in the high productivity management zone. Nutrient Management: We developed and evaluated a new technique of delineating site-specific production level
management zones (SSMZ). The objectives of this study were: (i) to compare our new SSMZ technique with a commercially available SCMZ technique, and (ii) to determine the optimum N-management strategy within the technique. The study was conducted on 2 irrigated cornfields over 2 years. The newer technique (SSMZ) of delineating management zone was in-conclusive in its ability to accurately delineate productivity level management zones. This could be attributed to the process of delineating management zones, where all GIS data layers were weighted equally. The resulting management zone map did not always reflect the generalized zones observed in last years yield map. Developing a mechanism of allocating appropriate weight to each GIS data layer may alleviate this fallacy. When comparing uniform N application with a variable yield goal approach, the variable yield goal approach was found to be the most efficient way of managing N. The apparent nitrogen use efficiency for the variable
yield goal approach was 1.2 to 2.0 times higher than the uniform N application approach.
Impacts
The development and adoption of productivity level management zone systems to better manage the inherent variability of farm fields is more profitable than conventional management approaches. The management zone approach will reduce over and under application of environmentally sensitive ag-chemical applications, maintain or increase grain yield, increase net profit, and enhance efficiency of agricultural inputs.
Publications
- Inman, D., R. Khosla, D.G. Westfall, and R. Reich. 2003. Spatial Nitrogen Uptake and Removal Across Site-Specific Management Zones. In Agronomy Abstracts, American Society of Agronomy, 95th Annual Meetings Denver, CO. CD-ROM.
- Farahani, H., R. Khosla, and G.W. Buchleiter. 2003. Field EC Mapping: A new tool to make better decisions. CSU Cooperative Extension Newsletter # 0.568.
- Khosla, R. 2003. Managing In-Field Variability. Extension Newsletter From the Ground Up Agronomy News on Managing Variability on your Farm. Nov-Dec. 2003. Vol 23, issue 6, pg 1-3.
- Koch, B. 2003. Economic Feasibility of Variable-Rate Nitrogen Application Utilizing Site-Specific Management Zones. M.S. Degree Thesis. Colorado State University, Fort Collins, CO.
- Koch, B., and R. Khosla, 2003. Book Chapter: The Role of Precision Agriculture in Cropping Systems. In. Cropping Systems: Trends and Advances. A. Shrestha (ed) The Haworth Press, Inc. 696 pp. Binghamton, NY 13904.
- Berry, J.K., J.A. Delgado, R. Khosla, and F. Pierce. 2003. Precision Conservation for Environmental Sustainability. 58 (6) 332-339.
- Koch, B., and R. Khosla. 2003. The Role of Precision Agriculture in Cropping Systems. J. Crop Prod. 8: 361-381.
- Hornung, A., R. Khosla, R. Reich, and D.G. Westfall. 2003. Evaluation of Site-Specific Management Zones: Grain Yield and Nitrogen Use Efficiency. Pg 297-302. In Precision Agriculture. J. Stafford and A. Werner (eds) Wageningen Academic Publishers 783 pp. The Netherlands.
- Gangloff, W., R. Reich, D. Westfall, and R. Khosla. 2003. Spatial dependence of soil samples and precision farming applications. Pg 223-228. In Precision Agriculture. J. Stafford and A. Werner (eds) Wageningen Academic Publishers 783 pp. The Netherlands.
- Westfall, D.G., W.J. Gangloff, R. Khosla, R.M. Reich, A. Hornung, D.F. Heermann, H.J. Farahani, and K. Fleming. 2003. Development of production level management zones for nitrogen fertilization. Pg 141-142. In Program book of the joint conference of ECPA-ECPLF. A. Werner and A. Jarfe (eds) Wageningen Academic Publishers, The Netherlands. Pp 846.
- Koch, B., R. Khosla, M Frasier, and D.G. Westfall. 2003. Economic Feasibility of Variable-Rate Nitrogen Application in Site Specific Management. In Proceedings of the Western Nutrient Management Conference, March 6-7, 2003 Salt Lake City, UT. 5:107-112.
- Khosla, R., B. Koch, and D.G. Westfall. 2003. Precision Nutrient Management on Site-Specific Management Zones. In Proceedings of the 15th Annual High Plains No-Till Conference Feb. 4-5, 2003, Greeley, CO. pg L1-L4.
- Inman, D.J., R. Khosla, D.G. Westfall, and R.M. Reich. 2003. Spatial variability in nitrogen uptake across site-specific management zones in irrigated corn. In Agronomy Abstracts, Western Society of Crop Science Annual Meetings, Fort Collins, CO June 22-24, 2003. pg 4.
- Hornung, A., R. Khosla, R. Reich, and D.G. Westfall. 2003. Evaluation of Site-Specific Management Zones: Grain Yield and Nitrogen Use Efficiency. Pg 223. In Program book of the joint conference of ECPA-ECPLF. A. Werner and A. Jarfe (eds) Wageningen Academic Publishers, The Netherlands. Pp 846.
- Gangloff, W., R. Reich, D. Westfall, and R. Khosla. 2003. Spatial dependence of soil samples and precision farming applications. Pg 204. In Program book of the joint conference of ECPA-ECPLF. A. Werner and A. Jarfe (eds) Wageningen Academic Publishers, The Netherlands. Pp 846.
- Westfall, D.G., W.J. Gangloff, R. Khosla, R.M. Reich, A. Hornung, D.F. Heermann, H.J. Farahani, and K. Fleming. 2003. Development of production level management zones for nitrogen fertilization. Pg 332. In Program book of the joint conference of ECPA-ECPLF. A. Werner and A. Jarfe (eds) Wageningen Academic Publishers, The Netherlands. Pp 846.
- Woodward, C., R. Nelson, R. Khosla, R. Riech, R. Hoffer, and P. Westra. 2003. Color Infra-red Imagery for Detection and Mapping of Jointed Goatgrass (Aegilops cylindrical) and Kochia (Kochia scoparia) In Winter Wheat. In Agronomy Abstracts, American Society of Agronomy, 95th Annual Meetings Denver, CO. CD-ROM.
- Westfall, D.G., W.J. Gangloff, R. Reich, R. Khosla, D.F. Heermann, H.J. Farahani, and K. Fleming. 2003. Indentification of Production Level Management Zones and Accuracy Level Verification. In Agronomy Abstracts, American Society of Agronomy, 95th Annual Meetings Denver, CO. CD-ROM.
- Khosla, R., A. Hornung, R. Reich, and D.G. Westfall. 2003. Yield Maps and Soil Properties to Delineate Site-Specific Management Zones. In Agronomy Abstracts, American Society of Agronomy, 95th Annual Meetings Denver, CO. CD-ROM.
- Khosla, R. D.G. Westfall, B. Koch, M.Frasier, and K. Fleming. 2003. Production Level Management Zones for Fertilizer Management: Are they profitable? In Agronomy Abstracts, American Society of Agronomy, 95th Annual Meetings Denver, CO. CD-ROM.
- Khosla, R., R. Flynn, and T. Shaver. 2003. Precision Agriculture Management: An Educational Program. In Agronomy Abstracts, American Society of Agronomy, 95th Annual Meetings Denver, CO. CD-ROM.
|
Progress 01/01/02 to 12/31/02
Outputs
This is a multi-disciplinary, multi-agency, multi-location, and multi-year project. Over the past several years growers have begun to adopt and implement precision farming technologies. However, growers and practicing consultants continue to question the profitability of this technology. No data currently exists in the Western Great Plains region demonstrating the economic feasibility of precision farming technology. One of the objectives of this project is to assess the economics of uniform nitrogen (N) fertilizer application versus variable-rate N fertilizer application on farm fields. The assessment includes various N management strategies (i.e., grid soil sampling based on N application, production level management zones based on N application, uniform yield goal based on N application, and variable yield goal based on N application) that are commercially practiced in the region. The economic analysis compared and contrasted the costs of each strategy to determine
which method of nitrogen application is the most profitable. Analysis for this aspect of the project was performed on data collected from one furrow-irrigated and two center-pivot irrigated cornfields in northeastern Colorado. Using the Profit and Loss (PAL) Enterprise Budget software developed by Colorado State University and USDA, operation schedules and enterprise budgets were constructed specific to each site to analyze the economics of each application strategy and to establish the most profitable one. The market price for corn was established as $2/bu. The net returns for the N management strategies were computed by subtracting total operating cost and total ownership costs from gross revenue. The analysis suggested that variable-rate N applications utilizing a site-specific management zones approach based on variable yield goal (SSMZ-VYG) was more economical than conventional uniform applications. Results from the study over three sites consistently indicates that less total N
fertilizer was used with SSMZ-VYG approach than with uniform N management, indicating a reduction in over- and under-application of N fertilizer, and an increase in N use efficiency due to identification of site-specific management zones. The variable rate N applications increased net returns from $13 to $29 per hectare compared to uniform N applications.
Impacts
The development and adoption of productivity level management zone systems to better manage the inherent variability of farm fields is more profitable compared to conventional uniform N application. A management zones approach will reduce over and under application of environmentally sensitive N, maintain or increase grain yield, increase net profit, and enhance efficiency of agricultural inputs.
Publications
- Khosla, R., K. Fleming, J. Delgado, T. Shaver, and D. Westfall. 2002. Use of Site Specific Management Zones to Improve Nitrogen Management for Precision Agriculture. J. of Soil & Water Conservation. Vol. 57 (6) 513-518.
- Anderson-Cook, C., M.M. Alley, R. Khosla, R. Noble, and J.F.K. Roygaurd. 2002. Differentiating Soil Types Using Electromagnetic Induction and Crop Yield Maps. Soil Sci. Soc. Am. J. Vol 66 (5) 1562-1570.
- Mzuku, M. 2002. The relationship between measured soil properties, site-specific management zones, and bare soil reflectance. MS. Thesis, Colorado State University.
- Khosla, R. 2002. Agricultura de Precision: Zonas de Manejo Especifico para Manejo Eficiente de Nitrogeno. In Proceedings of the Xth International Congress of No-till Farmers, AAPRESID, August 13-16th, 2002, Rosario, Argentina.
- Mzuku, M., R. Khosla, F. Smith, T. Shaver, R. Reich, and L.H. MacDonald. 2002. Relationship between Soil Properties and Productivity Level management Zones. CD-Rom Abstracts of the American Society of Agronomy meetings, Nov 10-14, 2002, Indianapolis, IN.
- Koch, B., R. Khosla, M. Frasier, and D. Westfall. 2002. The Economic Feasibility of Variable Rate N Applications in Irrigated Corn. CD-Rom Abstracts of the American Society of Agronomy meetings, Nov 10-14, 2002, Indianapolis, IN.
- Hornung, A.J., R. Khosla, R. Reich, and D. Westfall. 2002. Site-Specific Nitrogen Management Zones: Utilization of Yield Map and Soil Properties. CD-Rom Abstracts of the American Society of Agronomy meetings, Nov 10-14, 2002, Indianapolis, IN.
- Shaver, T., R. Khosla, W. Gangloff, and D. Westfall. 2002. Evaluating Nitrogen Management Techniques on Production Level Management Zones. In Abstracts of the Western Soil Science Society Conference, June 2002, Ft. Collins, CO.
- Khosla, R. 2002. Precision Farming Strategies in Western Great Plains Irrigated Agriculture Research Project. Better Crops 2002. Vol. 86. No. 4 p. 23.
- Broner, I., W. Bausch, D. Westfall, and R. Khosla. 2002. Decision Support for Crop Management Using Remote Sensing, Proceedings of World Congress of Computers in Agriculture and Natural Resources. Mar 13-15th 2002. Iguacu Falls, Brazil.
- Woodward, C., R. Khosla, and P. Westra. 2002. Detection and Management of Jointed Goatgrass Using Remote Sensing and Site-Specific Technology. CSU-AES Technical Report TR 02-7 p. 18-19.
- Khosla, R., K. Fleming, W. Gangloff, D. Westfall, and T. Shaver. 2002. Developing, Delineating, and Managing Production Level Nutrient Management Zones. In Proceedings of the Great Plains Soil Fertility Conference, March 5-6, 2002. Denver, CO.
|
Progress 01/01/01 to 12/31/01
Outputs
Spatial and temporal variability of yield limiting factors has been recognized for a long time. However, farmers continue to manage their fields uniformly because they lack the technology and understanding to manage this variability. There is a need for sustainable, profitable, and environmentally responsible methodology of managing today's farm. Managing farms site-specifically, based on spatial distribution of weed-seed bank, or insect populations, or spatial soil color, topography, farmer's experience, etc, by delineating in-field management zones for various inputs and managing such zones variably, has the potential to improve the efficiency of the whole agricultural system in a profitable and environmentally responsible manner. During the first year (2001) of this study different techniques of delineating management zones were used to develop productivity level management zones on 4 different field locations in NE Colorado for two crops, corn and onions.
Different scientists and their co-workers performed various measurements related to their area of work (nutrients, weeds, insects, diseases, and irrigation management) within each zone. Variable rate Nitrogen application treatments were made across management zones on all corn fields. Nutrient removal and uptake samples were taken throughout the season for estimating nutrient use efficiency. Grain yields were harvested using GPS linked yield monitor equipped combine. Data analysis to differentiate grain yield performance among treatments is in progress. Three corn fields, were evaluated for weed population dynamics utilizing a GPS receiver and field computer to geo-reference the information. Weed information by genus and species was collected on a 0.33 acre grid in all three fields. Weeds encountered included foxtail, field sandbur, barnyard grass, redroot pigweed, and hairy nightshade. Weed densities per species ranged from 0.3 to 4.4 per quadrat, and varied across the fields. Data
are being analyzed and will form the basis for temporal comparisons of weed population dynamics over a 3-year period. Plant infesting stages of Banks grass mite, European corn borer, western bean cutworm and western corn rootworm were sampled weekly during the growing season at two locations. Five observation sites were established in each of three productivity-level management zones at each location. Yields were taken from insecticide-protected and unprotected plants at each observation site to determine treatment benefit by management zone. Yield data are still being analyzed, but since pest densities were generally low it is unlikely that insecticide treatment benefits will be of much significance for the 2001 growing season. Microclimatic dataloggers (20) were placed within and outside of the canopies of two onion varieties at one research site to measure air temperature, water and leaf wetness patterns throughout the growing season in relation to crop growth and plant disease
development. Only a trace amount of bacterial soft rot developed in the field after a mid-season storm, and did not influence any treatment.
Impacts
The development and adoption of productivity level management zone systems to better manage the inherent variability of farm fields should reduce environmentally sensitive agricultural inputs, maintain or increase grain production, increase net profit, and enhance efficiency of agricultural inputs.
Publications
- Khosla, R., R. Reich, K.L. Fleming, D.G. Westfall, and D.L. Heermann. 2001. Evaluating Nutrient Management Zones Through Soil Test Parameters Over Three Years. Western Nutrient Management Conference Proceedings. Vol. 4. p. 192.
- Khosla, R., T.M. Shaver, R.M. Reich, and W.J. Gangloff. 2001. Evaluating Management Zones for Variable Rate Nitrogen Management in Corn. Third International Conference on Geospatial Information in Agriculture and Forestry Proceedings. CD-Rom.
- Khosla, R. and T.M. Shaver. 2001. Precision Ag Course and Curriculum at Colorado State University. Agronomy Abstracts. CD-Rom.
- Khosla, R., K.L. Fleming, D.G. Westfall, and T.M. Shaver. 2001. Management Zones: A Precision Tool for Farmers. Agronomy Abstracts. CD-Rom.
- Khosla, R., J.A. Delgado, T.M. Shaver, R.M. Reich, and W.J. Gangloff. 2001. Precision Farming for Nutrient Management. Agronomy Abstracts. CD-Rom.
- Khosla, R., J.A. Delgado, T.M. Shaver, and R.M. Reich. 2001. Nitrogen Management for Precision Agriculture. Soil and Water Conservation Proceedings. CD-Rom.
- Gangloff, W.J., R.M. Reich, D.G. Westfall, and R. Khosla. 2001. Delineation of Soil Management Zones: A Non-Grid Based Approach to Precision Farming Applications. Third International Conference on Geospatial Information in Agriculture and Forestry Proceedings. CD-Rom.
- Fleming, K. L., D. G. Westfall, D. W. Wiens, and M. C. Brodahl. 2001. Evaluating farmer defined management zone maps for variable rate fertilizer application. Precision Ag. 201-215.
- Fleming, K L., D. G. Westfall, and W. C. Bausch. 2001. Evaluation of management zone technology and grid soil sampling for variable rate nitrogen management. Proc 5th Int. Conf on Precision Agr. P. 12-22.
- Gangloff, W. J., R. M. Reich, and D. G. Westfall. 2001. Utilization of an autocorrelation matrix in principle component kriging. Agron. Abs., Amer. Soc. of Agron., Madison, WI.
- Gangloff, W. J., R. M. Reich, D. G. Westfall, and R. Khosla. 2001. Management zones for implementation of precision agriculture: Non-grid sampling approach. Agron. Abs., Amer. Soc. of Agron., Madison, WI.
- Fleming, K. L. and D. G. Westfall. 2001. Evaluating management zone technology and grid soil sampling for variable rate nitrogen application. P. 179-184. In Proc. Western Nutrient Management Conf. March 8-9, 2001. Salt Lake City, UT.
- Gangloff, W. J., R. M. Reich, D. G. Westfall, and G. A. Peterson. 2001. Statistical analysis applications in precis ion agriculture. P. 185-191. In Proc. Western Nutrient Management Conf. March 8-9, 2001. Salt Lake City, UT.
- Walter, S. 2001. Sampling patterns and spatial variability of three insect pests in sprinkler irrigated corn in eastern Colorado. M. S. Thesis, Colorado State University.
- Westra, P., L. Wiles, and D. Wyse-Pester. 2001. Using precision agriculture technology to evaluate factors, including weeds, that influence irrigated corn yields. Proceedings WSWS 54:64.
- Westra, P., F. Trucco, J. Miller, J. Withrow, and L. Wiles. 2001. Using Precision Agriculture Technology to Evaluate Weed and Insect Factors That Influence Irrigated Corn Yields.
- Anderson-Cook, C., M. Alley, J. Roygard, R. Khosla, R. Noble, and J. Doolittle. 2001. Differentiating Soil Types Using Electromagnetic Induction and Crop Yield Maps. Agronomy Abstracts. CD-Rom.
- Ceplecha, Z.L., R.M. Waskom, T.A. Bauder, J.E. McCray, and R. Khosla. 2001. Regional and Field Scale Methodologies for Assessing Aquifer Vulnerability to Nitrate Contamination. Agronomy Abstracts. CD-Rom.
- Khosla, R. 2001. Zoning In On Precision Ag. From the Ground UP, Agronomy News. Vol. 21, Issue 1. p. 1-4.
- Khosla, R. 2001. Strategies For Stretching Nitrogen Fertilizer Dollars. From the Ground Up, Agronomy News. Vol. 21, Issue 2. p. 1-3.
- Khosla, R., and T. Shaver. 2001. Zoning in On Nitrogen Needs. From the Ground Up, Agronomy News. Vol. 21, Issue 2. p. 16.
- Waskom, R., and R. Khosla. 2001. Nitrogen Application. From the Ground Up, Agronomy News. Vol. 21, Issue 2. p. 14-15.
|
|