Before midseason rolls into tasseling and pollination, make sure you’ve gathered all the information you need through scouting up to this point. That includes two important parameters that directly tie back to planter performance: stand counts and plant spacing checks.

Dan Quinn, Purdue Extension corn specialist, takes early and midseason observations on cornfields that are part of trials, and he encourages farmers to collect the same type of information. He says if you have information on how uniformly the stand emerged, final stand counts and spacing, you can make observations about planter performance and diagnose causes of less-than-stellar results.

Stand counts

“Many growers reach 95% stand compared to their seeding rate, and some today are considerably higher than 95% with advanced planter technology,” Quinn says. “If you’re not reaching 95%, then you may want to take a closer look at your planter to figure out why not.

“However, the whole point is, you don’t know how planter performance stacks up unless you take stand counts at several locations.”

Suppose you planted 32,000 seeds per acre. At 95%, final stand should be around 30,400 plants per acre. (Note that this example doesn’t account for germination losses.) If you dropped 32,000 seeds, but the stand is only 28,000 plants, then the planter only achieved 87.5% efficiency.

Related:How well will corn pollinate this year?

Track down the causes, Quinn says. Determine if seed was dropped and didn’t germinate or if it wasn’t dropped. If it didn’t germinate, was it placed too shallow or too deep? Or was there too little or too much down pressure on row units? Begin eliminating possibilities.

Plant spacing

Not as many people talk about plant spacing today. That’s not because it isn’t important, Quinn says. Instead, modern planters set correctly do an excellent job of spacing plants. And tests by Purdue and other universities over the past three decades drove home the message that plant spacing matters. Very poor spacing can result in yield losses approaching 5%.

TRACK THE CAUSE: If you have this much variation in plant spacing consistently across a field, return to your planter and figure out why. Poor spacing costs money.

How do you measure plant spacing? Simply grab a tape measure and begin recording distances in inches between plants down the row. Repeat this with several rows at several locations. Then average your numbers.

Programs are available to calculate standard deviation of error related to plant spacing. That’s a mathematical measure of how much spacing varies. The higher the standard deviation, the more variable the plant spacing. Values of 2 or less for standard deviation are desirable, Quinn says. If standard deviation on plant spacing approaches or exceeds 3, yield losses are possible.

“If plant stand counts or plant spacing numbers are way off, it pays to figure out why and correct it for next season,” Quinn says.

Across the rows:
How to describe 2024 corn crop? Variable

Variability is the watch word for corn across the Corn Belt this year, and the crop appears to be getting more variable all the time. Extreme heat and dryness in parts of the country and flooding elsewhere really increased variability over the last part of June.

Here are reports from different locations:

In Wisconsin. “Sometimes crop report summary data is all you need to know. Here are two key gleanings from the latest USDA weekly report for Wisconsin: First, topsoil moisture condition rated 0% very short, 0% short, 53% adequate and 47% surplus. Subsoil moisture condition rated 0% very short, 0% short, 62% adequate and 38% surplus. Second, the first cutting of alfalfa hay was 83% complete, 13 days behind last year and six days behind average.” — compiled by Fran O’Leary, editor of Wisconsin Agriculturalist

In Missouri. “Tar spot is here, and corn in my area is approaching R1, but it really varies in size from place to place. I have some replant acres that are only at V3. Long harvest to come!” — compiled by Mindy Ward, editor of Missouri Ruralist

In Nebraska. “Typical to the Cornhusker State, it is a tale of two extremes. Gov. Jim Pillen issued a state of emergency to help battle a raging wildfire in the dry Panhandle that has already claimed around 10,000 acres. At the same time, several rivers and streams in eastern Nebraska are swollen with excessive rain, with low-level flooding taking place, claiming crops along stricken watersheds. Traveling the eastern and east-central parts of Nebraska, it is difficult to find many low-lying fields that do not have standing water after this past weekend [June 23]. Corn that is not under water is doing well, growing fast, and many fields will be shoulder height or better by July 4. 

“The fact is crops are spread out. Early-planted corn and soybeans are right on schedule, but there are plenty of late-planted fields that need to catch up. 

“Pastures, in the wetter regions, have probably never looked better this time of year.” — compiled by Curt Arens, editor of Nebraska Farmer

In Iowa. “There is extreme flooding in 24 northwest counties; the rest of the state is not flooding but wet. I imagine it’s too early to know the full extent of damage but expect some total losses. Where not total losses, probably a lot of farmers are looking at their disease management programs now and late-season N applications.” — compiled by Gil Gullickson, editor of Wallaces Farmer

In Illinois. “On the day fields and towns were flooded in northwest Iowa and surrounding areas, our corn was rolling like pineapples. We got some rain later in the week.” — Holly Spangler, editor of Prairie Farmer

In Indiana. “On the day fields flooded in northwest Iowa, some of the corn in central Indiana was waist high and got a good drink over the weekend [July 23]. It looks good right now, but not all of Indiana has corn this tall or got the weekend rain.” — Tom J. Bechman, Farm Progress Midwest Crops editor