Replication, Randomization, and Treatment Design Concepts for on-Farm Research.

For most agronomists, randomization and replication and fundamental concepts that have a nearly sacred or spiritual status. They are an integral part of nearly all of our field-based activities. Some on-farm research falls into this category, simply because it is driven and designed by researchers who use working farms as research sites. While farmers might be driving initial research questions and hypotheses, this type of research is designed and conducted by researchers who are generally using all the standard rules for randomization and replication, especially if publication in a peer-review journal is one of the desired outcomes. In these situations, the only special needs would be the possible presence of more extreme spatial variation than one might find on a research station, necessitating more complex designs and data analysis methods. In contrast, participatory research, in which the farmers and researchers are both involved in various stages of the research, including the design, requires more flexibility for randomization, replication, and/or treatment design. Compromise, imagination, and careful definitions of research goals and outcomes are key elements in the design of participatory on-farm research. Often, such research does not involve replication in the classical sense of station-based agronomic research, so all participants must carefully define their goals and desired outcomes to design experiments that meet everyone's needs. Imagination, flexibility, and open-mindedness are key elements to this process.