With the global need for grain continuing to rise, increasing corn yields to meet demand is imperative. Fortunately, there continue to be improvements with planter technology that can help.
For about 20 years now we’ve been talking about how corn plants need to emerge at the same time so each plant has an equal opportunity to thrive. When plants right next to each other come up at the same time, we find a consistency in the height where the ear can be found on the corn plant, as well as an approximately equal size of one ear compared to the next. Recently farmers like Randy Dowdy and David Hula have been preaching this message to farmers, as even emergence has helped these two produce world-record yields.
If you are a farmer, one of the ways you can see how your planter is performing is by pulling the ears off 1/1000th of an acre in each row, then laying out the ears on a tarp just how they were pulled in the field. Here’s an example from our farm:
We pulled 24 rows because we have a 24-row planter. We then weighed everything out to get approximate grain bushels per acre, subtracting the cobs, of course.
The highest yield in a particular row was 230 bushels per acre. The lowest was 166. Since pulling all these ears takes a lot of time, we didn’t replicate it throughout the field, but as we walked the field checking ears, we do not believe we had quite as much inconsistency in the worst rows as what appears in this picture. Nevertheless, the key question here is, “Why?”
Why were certain rows worse than others? With a planting population of roughly 33,000 plants per acre and a standard corn germination percentage of 95, why didn’t 95% of the plants come up in each row? For the plants that did come up, why were some of them behind the others?
With modern planters there are more controls and adjustments than ever before, so here are three key things we look at on our farm. First, do we have the best technology on our planter? With recent advancements in things like down-pressure controls and closing wheels, we make at least some change almost every year.
Second, is every single moving part in great working order every day? With a 24-row planter, this is a lot more work than when we used to run an 8-row planter when I was a kid. That’s three times as many rows, but with all the gadgets we have on the planter today, in total there are probably ten times as many things to look at.
Lastly, nothing beats checking how the planting is done by digging in the soil. For us, we plant corn in dramatically different soil types, moisture conditions, fertility levels, residue content, and tillage situations. That means we need to make adjustments from field to field and day to day. Ultimately what we’re after is consistent seed depth (around 2.25” most of the time), consistent seed spacing (an equal distance from one plant to the next in each row), and consistent seed-to-soil contact. We need to make sure each seed has soil firmly pressed around it so it has the best chance to germinate quickly.
Increasing yield is the goal of every corn farmer, and the first step is making sure the planter does the best job it possibly can.