Pre-Harvest Corn Scouting for Stalk Integrity

Pre-harvest is one of the most important times of the growing season to scout corn fields. This allows growers to recognize potential issues, especially stalk integrity concerns, and be proactive to help mitigate harvest challenges. Many factors lead to standability problems such as weather, disease pressure, nutrient deficiencies, or a combination of factors.

The most common fundamental cause for standability issues is simply the physiological process of the plant re-allocating carbohydrates from the stalk to the ear during kernel fill. Under stressful conditions, such as nutrients loss, lack of rainfall during grain fill, or high disease pressure, corn products, particularly those with high yield potential, are at greater risk for stalk integrity concerns. Some corn products stand stronger than others after maturation, but it is important to carefully scout all products, particularly under challenging growing conditions (Figure 1).

Two easy ways to assess stalk strength are the push and pinch tests. For the push test place your hand above the ear and push the corn stalk sideways until the top of the plant touches the next corn row. When you release the plant, some will spring back to the original position, and some may remain leaned. If 10 percent or more of the plants are weak or stay in the leaned position after pushing, the field is at risk for lodging. To perform the pinch test, pinch the stalk between your fingers 6 to 12 inches above the ground. Weak stalks will feel hollow and are easy to collapse, while strong stalks will feel firm. Like the push test, 10 percent or more plants with weak stalks may indicate lodging risk.

Scouting prior to harvest and through the fall is one of the best ways to mitigate the risks associated with lodging. Regardless of what caused weakened stalks, it is important to identify issues as early as possible and adjust harvest plans to capture as much yield as possible.

Channel Agronomist
Baylee Jordan

1310_444726