Depending on where you are located across the country, acres can be left fallow for many different reasons including crop failure from hail, saturated soil conditions and rotational management in arid climates where limited precipitation may not allow continuous cropping management. Regardless of the reason for fallowing acres, there are a few key considerations that should be addressed when planting a crop in the following season.
Weed management is a core pillar of all cropping systems and is extremely important when managing and planting into fallow acres. Uncontrolled weed populations during a fallow season can lead to considerable yield loss for the following crop cycle due to increased weed seed banks, which can cause nutrient deficiencies and valuable soil moisture removal in arid climates. Additionally, fields with uncontrolled grass pressures, ragweed, waterhemp and volunteer corn can play host to the corn rootworm beetle whose hatched larvae the following year can impact corn products when a corn rootworm trait is not normally planted. A spring burndown herbicide program may need to be considered when evaluating weed pressures prior to planting. Herbicide labels for plant-back restrictions should be followed to help limit the potential for crop injury.
Another core pillar of cropping systems is soil fertility which should be considered when planting into fallow acres. Depending on local conditions, residual nitrogen that should be available in the soil profile may have been lost due to saturated conditions leading to denitrification and leaching. Understanding nutrient availability in the profile should be done prior to planting through soil sampling; management and applications decisions should be adjusted accordingly to results and yield goals. Mycorrhizal fungi colonization plays an import role in overall soil health and acts as an extension of crop root systems which aid in nutrient and water uptake. Fallow periods can cause a reduction in colonization due to the absence of a host crop as well as saturated soil conditions that hinder development. Corn is especially susceptible to reduction which can lead to fallow syndrome which is observed as purpling of young corn seedlings, signifying phosphorus (P) deficiency. Often, soil tests may show that adequate P levels are in the soil and this purpling is due to a buildup of anthocyanin in the leaf tissue of corn seedlings. However, a banded application of P with the corn planter is a good practice to help ensure P is available to enhance corn seedling growth and development.
Many factors should be considered when planting into fallow fields; decisions and outcomes can vary by crop. Working with your local Channel Seedsman and Channel support team can help position and manage the best product for each situation.