CSI: Corn Stand Investigation or Crop Stand Investigation

BY Dairyland Seed Agronomy Team

A few years back there was a TV station airing the show CSI: Crime Scene Investigation. For most agronomists, science and biology are of great interest. Additionally, we are intrigued by the way crops perform and the reasons behind that performance.

One of the agronomic activities we find fascinating is walking fields just after emergence. We are looking for missing corn seedlings or perhaps it’s a damaged plant. As a crop producer, it may not be as satisfying, but your Dairyland Seed professional enjoys the challenge of finding out why and what happened to the missing, sick, dead, or dying plant. It is extremely difficult to evaluate why there was a skip in the row in October so just after planting is an ideal time to give those Red Wings or Wolverine boots a workout.

You’ll need a few items: a shovel or trowel (this time of year the smaller trowel is sufficient), pocketknife, tape measure, a hula hoop for drilled beans, a good reference like the Purdue Corn and Soybean Field Guide and something for recording information such as good old paper and pencil, or an iPad or smartphone with Corteva’s Granular app. The techno version lets you record where a certain issue is identified by identifying the exact position through GPS the coordinates. I like to walk a W or V pattern through the field, but field dimensions and shape change that. The important thing is to try to reach all the major growing environments within that field -- clay knobs, poorly drained areas, old weedy patches etc.

Comparing roots and planting

What to look for? We want to know: Was it a seed quality issue? A planter issue? Insect or disease? Some of these things we can control or minimize; others, well, we just can’t.

First off, we will want to know if a seed was actually there. If not, and there is a high frequency of missing seed, then we need to take a trip to the tool shed and take a peek at the planter. If there is a seed present, then we want to do the real CSI type stuff. Examine the seed or seedling and determine its demise. Was it a murderous insect consuming the life right out of the plant or a rotten plant disease? Or perhaps it was planting depth or soil conditions. I always get a little concerned when I can see a seed slot weeks after planting. Typically, that tells me it was a “little” wet at planting. Just remember the sins of planting last all year long. So, make a mistake early in the season and you live with the consequences.

Black cutworm

From an insect standpoint, common pests that attack seeds or seedlings to look for are seed corn maggots, wireworms, white grubs, and black cutworms. Many of these are controlled or suppressed through seed treatments and seed traits. From a pathological standpoint, we need to be concerned about seedling blights, especially during cold wet periods.

Black cutworm hiding in soil and damaged plant

In summary, time spent walking fields at and soon after emergence may well identify a problem that can be corrected. If it is something that cannot be fixed this year, it may provide valuable information for next year’s crop.

I strongly recommend recording this information so that you can better analyze this year’s issues and begin now to plan for improvement for next year. Most importantly, if there are issues you cannot figure out, contact your local Dairyland Seed representative.