Late-planted Corn Yields Surprisingly Well

Indiana Prairie Farmer/Purdue test plot tops at 242 bushels per acre.

Published on: Oct 25, 2010

The harvest of the Indiana Prairie Farmer/Purdue University Tippecanoe Extension/ Precision Planting Plot last week revealed an interesting surprise. Planted the last week of May due to wet weather early and research restrictions, most of the plots were in the 150 to 200 bushels per acre range. That was surprising, considering the dry summer at Lafayette. Rainfall was scarce form late July through harvest.

The top individual plot yielded 240 bushels per acre, although most were considerably below that figure. The lowest yield was 99 bushels per acre. It was in a wet spot that turned yellow after planting, and was infested with giant foxtail early. A post-spray application did a tremendous job on stomping out weeds, even though corn was at the V7 stage when it was applied.

It's still too early to tell if the treatments made a difference in the plot. This trial compared driving speed at planting, seeding depth and downpressure setting in 17 combinations. The goal was to find which combination worked best.

Surprisingly, the one-inch depth came up last and tended to not look as well all season. Germination was slower and more erratic. Jeff Phillips, Tippecanoe Extension ag educator., speculates that the worked soil dried out and the one-inch corn didn't germinate until it rained about a week later. The deeper depths probably got an earlier start.

What the plot did take the distinction for was likely being some of the wettest corn harvested this late in the season this area. Moisture contents ran in the 15 to 16% range. Most corn ahs come out of the field at 12% or below lately, with one report putting moisture as low as 10% coming out of he field,.

"Any other year that would seem dry," Phillips notes. Moisture content and test weight were measured on each individual plot. Test weights tended to run in the 57 pound per acre range. This year, most farmers have not had to dry corn through a dryer. Some have dried it with aeration this year.

Phillips will soon analyze the date. He is also analyzing data from stand placing measurements to check for standard deviation. That is to determine accuracy of the planter itself at the various settings.

More talk has sprung up about tension on planter units being correct lately. That's why changes in adjustment in tension of row units was included as a factor.

The seed for this test was furnished by 1st Choice Seeds.