Corn+Soybean Digest

How To Interpret F.I.R.S.T. Trials

It's independent, and it's comprehensive. F.I.R.S.T. has compiled more than 36,000 on-farm yield trials on 148 farms this year. Here's how those results have been collected and how to use the information:

  • F.I.R.S.T. testing is conducted across nine Corn Belt states: Michigan, Ohio, Indiana, Illinois, Iowa, Wisconsin, Minnesota, South Dakota and Nebraska; and three Mid-Atlantic states: Pennsylvania, Maryland and Delaware.

  • Participating seed companies pay to enter the top hybrids they select into the F.I.R.S.T. trials. Those companies supply high-quality lots of commercially available, medium flat grade seed for testing based on agreements established by F.I.R.S.T. A complete listing of the participating companies can be found starting on page 63.

  • Each hybrid tested is planted in a 4-row strip, 50 ft. long, with a 4-row, finger-metered planter. Only the center two rows are used to measure yield.

  • Test sites are selected based on uniform productivity, with added consideration given to topography, soil types and management practices common in the given region. This often requires planting additional turn rows to “push” the site away from areas that could unfairly impact hybrid performance.

  • In addition, the sites are organized so hybrids are grouped together in blocks from front to back and side to side. This allows for more precise comparison and the option to drop a block from consideration if some issue in the field disrupts the experiment.

Zone Summaries

Testing is grouped into standard zones for Central Relative Maturity (CRM). The maturity range per zone is as follows: Zone 3 (91- to 102-day CRM); Zone 4 (95- to 106-day CRM); Zone 5 (99- to 110-day CRM); Zone 6 (103- to 114-day CRM); Zone 7 (107- to 118-day CRM).

For F.I.R.S.T. information reporting, some of the zones are split to better accommodate interpretation. The zones listed are: Zone 3 West (3W); Zone 4 West (4W); Zone 4 East (4E); Zone 5 West (5W); Zone 5 East (5E); Zone 6 West (6W); Zone 6 East (6E); Zone 7; and Zone 7 East (7E).

As you'll note, each zone summary lists yield data for the current and previous years.

When a hybrid has been tested in more than one region or for more than one year, we also report yield advantage. That translates to the number of bushels above or below average yield in those regions. The zone summary pages also include pertinent test-site information, such as soil type, tillage, and plant population.

Regional Summaries

The zones are then split into separate regional summaries. For example, Zone 6E contains Illinois West Central (ILWC), Illinois East Central (ILEC), Indiana Central (INCE) and Ohio West Central (OHWC). These pages follow the zone summaries and highlight information from the six farmer-members who participate in the F.I.R.S.T. testing program for that particular region.

Individual hybrid information from each farm-site test plot includes yield, moisture, and lodging percentages averaged from three replications per farm, and then again as a regional average from the six farms.

In the cases where regional summaries have no information listed for a plot, those test sites are not included in the report due to growing conditions making the trial not harvestable for yield measurements.

Regional summaries also include the least significant difference (LSD) for a given plot. If you find the difference in yield between two hybrids, the LSD must be smaller than that number to conclude that the hybrids are “probably” different. The probability used is 90%.

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