By Mahdi Al-Kaisi, Department of Agronomy
With most of our corn and soybean planting completed or on its way to completion, it's time to think about the soil. Fields at this time are most vulnerable to soil erosion because of degraded crop residue cover during soil preparation by tillage, and the crop canopy is not yet present to protect the soil. Even fields with a relatively flat to moderate slope have shown some significant erosion during the past week's rain events. This is especially apparent in areas of the field where waterways can be very valuable in reducing soil erosion. It is time well spent to evaluate and take an inventory of your field for proper grass waterways placement and for repairing the existing grass waterways and buffer strips.
Springtime rain can come hard and fast as we experienced last week, causing substantial soil erosion. Field observations at this time can provide some insight on how to manage your field and protect your soil and water quality. The soil profiles in most of Iowa are now filled to capacity with water. Therefore, the amount of rain we receive can exceed the soil storage capacity, especially since plant water use is very low at this time of the year. Maintenance of grass waterways is essential to maximize the benefits and effectiveness of such practices in reducing soil erosion.
These conservation practices (i.e., buffer-strips, grass waterways, etc.) are critical for protecting soil quality and sustaining crop productivity. Also, the relationship between water quality and soil erosion cannot be over-emphasized; soil erosion and loss of top soil can have a huge impact on yield. Therefore, implementation of conservation practices can be significant in controlling soil erosion, and improving soil and water quality.
Areas in the field such as this indicate a need for a grass waterway.
Mahdi Al-Kaisi is an associate professor in agronomy with research and extension responsibilities in soil management and environmental soil science. He can be reached at email@example.com or (515) 294-8304.