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Make your test plot data work for you

One sign of an innovator is someone who does test plots to learn what he or she doesn’t know. Often the plots include products they’re not using yet. The smart way to try them is in test plots, not on major acreages.

If you’re a leader, you’ve probably got one or more tests growing this summer. How do you make sure you start building a good data set that will help you in selecting varieties you will plant in the future, or production practices you might adopt?

Key Points

• Strongly consider either a hybrid or agronomic practice test, or both.

• Design and use collection sheets that match your information needs.

• Test information becomes more valuable as you accumulate years of data.

Collection sheet

The first step is to make a data collection sheet. Customize it to the test you’re doing. The sample form shown here represents the type of data I collect on typical plots. I use a 1-to-9 rating scale for seedling emergence, early vigor, disease resistance, and root and stalk strength. In my scale, 1 is best and 9 is worst. You would assign a 5 to an average plot. It’s a simple and quick method to use to take notes in your plots.

Here’s a closer look at each factor I collect.

Seedling emergence: It’s a function of hybrid genetics and seed quality. Some hybrids emerge better in cold, wet ground than others. Having records helps you decide which to plant first if you’re planting early.

Early vigor: Rate hybrids that close the canopy faster higher.

Plant population density: Hybrids differ in how they respond to varying populations. Taking counts and recording them is a good check to see if you’re getting the stands you think you should.

Ear height: Rate hybrids as low-, medium- or high-eared. Or if you prefer, use a yardstick to actually measure from the soil to the node where the top ear attaches. A low-eared hybrid will generally be short, and a high-eared hybrid will generally be tall.

Disease resistance: Rate all hybrids from 1 to 9 for foliar disease at pollen shed. This provides an indication of which ones might respond best to fungicides. Repeat it at black layer. Hybrids with better stay-green power generally have a longer grain-full period.

Root strength: Hybrids that lean away from the straight vertical position by more than 30 degrees at soil level are considered root-lodged. The problem is poor rooting, not stalk quality.Stalk strength: If plants are broken below the ear, it’s stalk lodging.

Harvest data: Leave room to record test weight, grain moisture and yield for each hybrid or practice.

Plot value

Think of your test plot as a window to your other fields. If a certain hybrid shows disease problems in the hybrid test plot, look for similar situations wherever it’s planted.

If the plot was planted first, it works better as a guide to what might show up in fields. Planting plots first also lets you adjust planting equipment.

Accumulate test information. That will give you an excellent resource for making decisions about hybrid selection and production practices.

Use your hybrid test plot data to guide you as you discard the bottom third of hybrids every year. Replace them with newer products. Favor the hybrids in the top third of performance and the more consistent performers with more acres. The process should help you make more unbiased decisions and increase net profit over time.

Nanda writes from Indianapolis. Contact him at


This article published in the July, 2010 edition of INDIANA PRAIRIE FARMER.

All rights reserved. Copyright Farm Progress Cos. 2010.