Terry Griffin 1 , Craig Dobbins 2 , Jess Lowenberg-DeBoer 2

1. Terry Griffin1, Craig Dobbins2, Jess Lowenberg-DeBoer2 1University of Arkansas – Cooperative Extension Service 2Department of Agricultural Economics, Purdue University Case Study Evidence of New Opportunities for Farm Management Specialists in Spatial Analysis of On-farm Trial Data National Farm Management Conference

2. On-farm trials often violate statistical assumptions Farmers continue to conduct on-farm trials PA and GPS lead to resurgence of on-farm trials Harvested with yield monitors w/out interference Reduced public research funding More weight on local on-farm experiments Farmers’ objective: make best decision Motivation

3. Better understand the motivations of farmers for conducting field-scale experiments and document their perceptions of spatial analysis Propose plan to Extension and industry for spatial analysis service Goal of Case Study Research

4. Case studies evaluated perceptions of conducting on-farm research and spatial analysis Qualitative research methods Lack of general information to conduct quantitative survey Research Methods

5. Reference and comparison group farmers IL, IN, KY, Ontario Direct 3 year observation of reference group During farm-visits, frequent communication Farmers conducting field-scale on-farm trials Spatial analysis reports provided to farmers One-on-one interviews of both groups Two yield monitor data analysis workshops Multiple Case Study Data

6. Spatial statistics assume that data is spatially correlated and explicitly included in analysis; in contrast to independent observations assumption. Yield monitor and site-specific data is spatially correlated. If that correlation is not accounted for in the analysis, results will be biased and misleading. Yield monitor data with appropriate spatial analysis can lead to more reliable decision making with limited replications. Spatial Analysis: A Definition

7. Description of on-farm trial Design, treatment, data available Data handling procedures Yield data filtering, data assimilation Spatial statistical analysis and diagnostics Economic analysis Production recommendation Spatial Analysis Reports

8. Central Indiana soybean seeding rate trial 80, 100, 120, 140, and 160K seeds per acre 4 replications in 1700 foot strips 30 inch rows End result is more reliable information A production recommendation Not a map Example On-Farm Trial Photo: Griffin – Twilight Farms

9. Raw yield monitor data • As-is from the combine • No cleaning or filtering

10. Yield data in GIS after removing erroneous observations

11. Study area Yield data in GIS after removing erroneous observations

12. Yield monitor dataused in analysis

13. Rate trial: 80K to 160K seeds per acre Four replications of five population rates { 1 { 2 { 3 { 4

15. Major soil Secondary soil { Minor eroded soil All five rates on each soil “zone”

16. Spatial Error Estimation

17. Major soil: 130K yield max 2004 Soybean Seeding Rate Study Major soil : 100K profit max Secondary soil: 150K yield max Secondary soil: 120K profit max Can reduce input costs by lowering seeding population from 130K to about 100K on most of the field, increasing planting timeliness

18. November 2005 and March 2007 Farmers, consultants, university personnel Yield Data Analysis Workshops

19. Farmers some farmers perform own spatial analysis University Extension Technical skill, but can only work directly with a few farmers Private industry farmers, co-op, dedicated analysts, consultants Who should conduct spatial analysis?

20. Assist with designing experiments Network of research collaborators Regional research projects Continued education/training for analysts Troubleshooting and problem solving Teaching interpretation of analysis Assist with decision making Role of Extension

21. Already dealing with vast amounts of data Familiar with assisting interpretation of results Assist with whole-farm decision making Comparative Advantage for Farm Management Analysts

22. Farmers’ Willingness to Pay • Will farmers be willing to pay a fee that entices qualified analysts to offer service?

23. What software to assemble the data? What software to statistically analyze the data? R, GeoDa, Stata, SpaceStat, MATLAB, SAS What type of spatial analysis conducted? How characteristics of neighboring data used? Where received spatial analysis training? How confident are you in the results? Does client receive copy of original or raw data? Is focus on providing maps or recommendations? Third-party Spatial Analysts Questions

24. More confidence in data and decisions when using spatial analysis Farmers made more decisions more quickly Unclear who will be primary analysis provider Role for Extension and private sector industry Depends upon farmers’ willingness to pay Will any tax money be put into this? Are any public goods generated? Farm management specialists may be among the first to demonstrate benefits of the yield monitor Conclusions

25. Wish to thank USDA-SARE for providing funding to evaluate alternative on-farm designs and develop spatial analysis methods

26. Terry Griffin tgriffin@uaex.edu 501.249.6360(O) Craig Dobbins cdobbins@purdue.edu Jess Lowenberg-DeBoer lowenbej@purdue.edu