Battle for the Belt: Season 2, Episode 28 - Corn Harvest Considerations

Episode 28 of Battle for the Belt is now available: https://www.youtube.com/watch?v=MwjSjglBDYs

In Episode 28, we are in the field with Dr. Osler Ortez to cover more information on corn harvest considerations, including corn ear orientation and test weight.

As we embark on corn harvest, besides considering stalk quality and standability, another issue to keep an eye on is “droopy ears” (Figure 1). Droopy ears along with stalk lodging can occur because of late season drought stress and cannibalization in the plant (plants removing carbohydrates from the leaves, stalk, and roots to the developing ear). This can lead to premature black layer and reduced yields.

Additionally, if crop stress is present, test weight will be affected as well. Ears with low test weight reflect sub-optimum conditions during the second half of the reproductive stages (R3-milk to R6-maturity). From R3 to R6, moisture in the grain is going down, while dry matter accumulation is going up. Approximately 40-45% of grain weight is gained during the first half of the dent stage (R5) alone. By physiological maturity (R6), kernels have no milk line and have reached maximum dry matter accumulation.

Refer to this article for more information on corn stalk quality, droopy ears, and test weight: https://agcrops.osu.edu/newsletter/corn-newsletter/2024-31/dry-conditions-corn-stalk-quality-concerns

What’s happening in the field?
This past week at the Western location, planting date one and two were affected by the hurricane rains with pods exhibiting shattering and sprouting inside of the pod (Figure 2).

 The seeds imbibed the water and began to dry down, however, the seeds that sprouted are beginning to rot in the pod. This primarily affected plants on the earliest planting dates (March and April). The May to June planted soybeans were not affected as they were not as dry at the time of the rain. All planting dates are at R8 (full maturity), except for planting date five which is at R7 (beginning maturity) and still drying down (Figure 3).

The corn at this location had planting date one through four at R6 and all four of those planting dates were harvested. Planting date five was the only one that had standability issues after the storm and was the only one that suffered from wind lodging and was still at R5 (dent) (Figure 4).

The Northwest location has all planting dates of soybeans at R8 except for planting date five which is still at R6 (full seed). The first two planting dates of soybeans were harvested. In the corn the first two planting dates are at R6, while planting dates three four and five are all at different stages of R5.

The soybeans at the Wooster location are all at R8 except for planting date five which is still drying down at R7. The corn is at similar stages to the Northwest location with the first two planting dates at R6 and planting dates three, four, and five at R5.

The final planting dates at these more northern locations are a few weeks before black layer can be accomplished from a growing degree day standpoint.

The summary of locations, last week’s weather, planting dates, GDDs and stages is presented in Table 1.