The competitive nature of modern agriculture requires constant refinements of many crop production management decisions. Precision agriculture tools (PAT) can allow growers to rapidly evaluate different management practices across large areas at a relatively low cost. But a systematic approach and a decision-making process describing how to utilize different PAT for on-farm evaluations have not been yet developed and adopted. This presentation will focus on how  approximately 300 Iowa growers use digital aerial imagery, replicated strip trials (RST), and guided plant testing to evaluate a wide range of fertilizer and manure management practices, tillage, crop management, and different plant protection products on corn and soybean every year. About 30 grower groups were formed across the state to evaluate different agronomic topics. Specific protocols were developed for conducting RST, collecting, processing and analyzing trial data, and summarizing results. Every winter, grower group meetings were held to discuss results of >500 RST and identify new and relevant research topics. The results of individual evaluations, summaries for individual groups and summaries across the state were publically available on the website. Annual winter conferences attracted > 500 attendees to learn the statewide results, summarize, and develop evaluation strategies for the next year. The data were also summarized and published in a bi-monthly magazine. Four examples of 2009 statewide evaluations  were presented: “Injected Liquid Swine Manure plus 50”, “Injected Liquid Swine Manure with Nitrification Inhibitor”, “Spring Applied Urea Ammonium Nitrate Solution (UAN) with Nitrification Inhibitor”, and “Headline Fungicide on Soybean”.