The University of Minnesota Extension Service has an interesting tool to help you do a more professional job of analyzing results from on-farm field trials.

Paulo Pagliari, University of Minnesota Extension soil scientist, and Bruce Potter, U of M integrated pest management specialist, recently modified an online Excel spreadsheet that allows you to enter yields for two or three treatments (varieties, pesticides, fertilizers, etc.) with three to eight replications and calculate treatment averages and statistical differences. In addition to yield, the spreadsheet can calculate differences between crop stands; insect, disease and weed control tactics; and other variables.

“This spreadsheet is not, by any means, bug-free, polished software, but you might still find it useful,” Potter says.

Dowload it at swroc.cfans.umn.edu/farm-trials-worksheet.

More tips
Some tips on doing on-farm research from the U of M Extension Service include:

• Do not try to compare too many treatments in one trial. If you are trying to compare more than three or four treatments, then you should seek help from a statistician.

• Make sure you have a control treatment. Include a common treatment or untreated plots in your comparison.

• Avoid placing treatments in locations where cropping history or soil factors would affect treatments differently.

• Include replications (more than one plot for each treatment). Three or more replicates are needed to determine the consistency of results. Using multiple samples from the same plot or strip is not replication (they are pseudoreplications).

• Randomize the order in which your treatment plots/strips occur in the field (planting order of varieties, which plots receive which varieties).

• Understand how variability influences your ability to draw conclusions. Do you want to risk calling treatments different that are essentially the same, or do you want to risk not finding real treatment differences?

• Don’t over-extrapolate and assume the rest of your experiment has to be valid for other fields.

A comprehensive publication on conducting on-farm research can be found at sare.org/Learning-Center/Bulletins/How-to-Conduct-Research-on-Your-Farm-or-Ranch.