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Yield test for corn turns 90

Numerous generations of farmers have relied on what many still refer to as the Iowa Corn Yield Test. For years that was its name. For 90 consecutive years the test has been conducted at various locations in Iowa to provide information to help select corn varieties and hybrids to plant.

Yield test for corn turns 90

Numerous generations of farmers have relied on what many still refer to as the Iowa Corn Yield Test. For years that was its name. For 90 consecutive years the test has been conducted at various locations in Iowa to provide information to help select corn varieties and hybrids to plant.

Today, the official name of the annual statewide trial is the Iowa Crop Performance Test — Corn. Using the word “performance” instead of “yield” reflects that the test measures and compares more than just the yield. Marking its 90th anniversary in 2009, the testing program continues to be a cooperative project between Iowa State University and the Iowa Crop Improvement Association. The information is free.

“The program has succeeded all these years because of the farmers in Iowa and their use of the performance data and the many seed companies past and present that participate in the trials,” says Jim Rouse, program coordinator and executive director of ICIA. “Without the trust and support of both of these groups, the program could not have reached such a milestone.”

The goal is still the same as it was when H.D. Hughes and Henry A. Wallace suggested the idea and helped start the program in 1920. That is, to provide Iowa farmers with unbiased information about the corn they grow. Hughes was an agronomy professor at Iowa State College, as ISU was called back then. Wallace developed some of the first commercial hybrids and helped the seed corn industry get its start before he went on to become U.S. secretary of agriculture and vice president of the United States.

Key Points

• Tests help farmers select the best hybrids for their farms.

• Look for randomized, replicated data when evaluating varieties.

• Consider multiyear district averages to minimize risk.

What’s looks to a hog?

As editor of Wallaces Farmer, Henry A. Wallace wrote extensively about the promise of hybrid corn. An advocate of scientific methods, even as a teenager, he was critical of the practice of selecting the most beautiful ears and saving them for seed. Early in his corn breeding experiments, young Wallace realized a scientific selection process was needed instead of a “beauty contest” approach.

The first bulletin of test results, published in 1920, reported yields from a Benton County test that included data from 12 open-pollinated varieties, with names such as Reid’s Yellow Dent and Iowa 203. These 12 open-pollinated varieties averaged 63 bushels per acre, as ear corn. Data also were included from a 1918 test in Floyd County and a 1915 Henry County test. The 1921 test, which reflected the first official growing year, included 128 open-pollinated varieties.

In his book, “The Hybrid Corn-Makers,” Richard Crabb explains the important role the Iowa State Corn Yield Test played in development of the hybrid corn industry. Also, a book titled “The Iowa Crop Improvement Association,” by Joe Robinson and Oliver Knott, discusses the first 44 years of the test. Many changes in the corn yield testing program have occurred in corn production practices, data collection methods, statistical analysis and publishing of the results.

For many years the reports weren’t released until mid-February following the fall harvest. Today, the results are posted on the Internet as soon as Rouse and his crew can get the plots harvested and the results analyzed. Data for the first plots are usually posted soon after harvest in October, and complete data for all sites is posted in November. In fall 2009, with the late-maturing crop, wet weather and the latest Iowa corn harvest in more than 50 years, test results for all locations weren’t completely posted until Thanksgiving.

To get the first test started in 1920, the Iowa Corn and Small Grain Growers Association worked with the college, now ISU, planting test plots in the state that spring. The farmers of 1920 didn’t use corn hybrids. Instead, varieties of
open-pollinated corn were planted.

The first hybrid wasn’t entered in the test until 1923. In 1924, USDA offered an entry designated as “F1 Hybrid.” Henry C. Wallace, the father of Henry A., was then the U.S. secretary of agriculture. George Kurtzwell entered another hybrid, Copper Cross. More hybrids were entered in 1925, and by 1930 the hybrid entries outnumbered the open-cross entries. By 1938 only 63 of 1,110 entries were

The test was difficult work. In their 1963 book, Robinson and Knott said the
hand-held planters made “an awful” racket when dragged along a railroad depot platform. The early researchers often rode trains to their destination, then hired workers locally to help them plant and harvest.

Just a click away today

It wasn’t until 1960 when mechanical corn-pickers were used to harvest the plots. Today, combines are equipped with monitors and technology to gather information as the crop is harvested. Measurements for yield and grain moisture are made automatically.

The methods of delivery of information to the public also have changed. In the 1980s researchers still recorded data with a pencil and paper. Farmers had to go to the county Extension office to get a copy of the report, usually available after Christmas. Today, it’s just a click away on the Internet at www.croptesting.

Results of the Iowa Crop Performance Test — Corn and Iowa Crop Performance Test — Soybeans for 2009 are available at the Web site. These are reports of yield trial data from more than 300 corn hybrids and 320 soybean varieties tested. Both the corn and the soybean trials today are run in six districts, three locations per district, around the state.


LATEST YIELD TEST: Bill Vinson (right) and Bill Fjelland examine a plot during harvest of the 2009 Iowa Corn Performance trial in southern Iowa.


HARD WORK: Crews haul, sort and weigh ears for the corn yield test, circa 1950.


OLD DAYS: Chuck Hutchcroft (left in photo above) and Adin Rouze of the Iowa Crop Improvement Association evaluate hybrids in 1954.

This article published in the January, 2010 edition of WALLACES FARMER.

All rights reserved. Copyright Farm Progress Cos. 2010.

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