Published on Tuesday, February 6, 2018
Better Late Than Never?
Every year, Beck’s Practical Farm Research (PFR)® team evaluates, and then discusses, planting dates for corn. What is the ideal planting date for your region? Based on management practices including water management and tillage, can you get into the field during that timeframe?
When we listen to winners from the NCGA yield contest, one of the first things they tell us is we need consistency in emergence. One goal in PFR this year was to evaluate differences in emergence and determine how they impacted yield.
Let’s Talk Regional Differences
Typically, we see the best planting window at our Ohio PFR site in mid- to late April, as our yield potential starts to decrease when we plant in early June.
As we look at these different planting dates, it makes us question how much a delay in emergence really impacts yield.
Taking 12-hour Emergence Notes?
In 2017, we monitored emergence in both the planting dates that fell in the best planting window (mid-late April) and worst planting window (early June) for Ohio. The first plant that emerged was flagged, and we continued to flag plants every 12 hours until a full 17 ft. 5 in. section (full area for stand count) had emerged. These flagged plants were then monitored throughout the growing season. At the end of the season, these plants were hand harvested, shelled, and weighed and yield was then calculated to a per acre basis.
We first observed that full emergence of a plant stand took much longer with the April 26 planting date when compared to the June 15 planting date. This was no surprise given the particularly cool, wet spell that hit the area only two days after planting on April 26. Most of the plants had emerged within five days of planting while a few plants did not emerge until 13 days after the first plant emerged. In the case of the June planting date, all plants had emerged two days following the first emerged. The yield drag we observed with a 24-hour delay in emergence was over four times in June what it was in April.
Why is there such a stark contrast in emergence between the two dates? We suspect that these differences are due largely to GDU accumulation. When looking at the accumulation of GDUs in the five days following planting, only 64 GDUs were accumulated following the April planting date while 178 were accumulated in the five days following the June planting date.
When we evaluate these numbers, a few take home messages come to mind. First and foremost, the timing of emergence does matter. A uniform emergence can increase overall yield potential in a field.
Second, emergence is going to matter even more for late-season planting. We tend to rush to get the seed in the field during late planting or even replant situations but getting our planting depth and planter settings where we want them will be most critical later in the season to ensure a more uniform emergence in our stand, thus optimizing yield.
To view our regional results of the corn planting date study, click on the links below:
Author: Alex Knight
Categories: PFR, PFR Reports
Tags: corn, Emergence, PFR, PFR Report, Planting Date