By Blake Jackson
The decision to harvest corn stover from fields is a delicate balancing act, influenced by factors like livestock feed and bedding needs, soil health, and nutrient management goals. While corn stover provides valuable nutrients, its removal can negatively impact soil health.
Harvesting corn stover removes essential nutrients like phosphorus (P2O5) and potassium (K2O) from the field. These nutrients are crucial for subsequent crops, and their loss can be significant.
For example, removing a ton of 15% moisture stover can deplete the soil of 4.6 pounds of P2O5 and 32 pounds of K2O. Considering current fertilizer prices, the economic value of this loss is substantial.
Beyond phosphorus and potassium, corn stover also contains nitrogen, sulfur, and various micronutrients. While their economic value is less clear due to their tendency to leach through the soil, they are vital for soil health.
Harvesting corn stover can have short-term benefits, such as increased nitrogen availability due to reduced soil compaction.
However, frequent removal can deplete soil nitrogen over time, potentially reducing yields. Soil testing is essential to monitor nutrient levels in fields where stover harvest is common.
Grazing corn stalks is a less nutrient-depleting option compared to mechanical harvesting, as livestock return nutrients to the soil through their waste.
While leaving corn stover in the field offers numerous benefits, such as reduced soil erosion, it can also harbor disease-causing pathogens and insects.
Fields with a history of diseases like tar spot or ear and stalk roots may benefit from removing crop residue to prevent their spread. Additionally, leftover plant residue can provide shelter for insects like the western bean cutworm, potentially increasing their survival rates.
Therefore, the decision to harvest or leave corn stover should be based on careful consideration of various factors, including soil health, nutrient needs, pest management, and the specific conditions of your farm.
Photo Credit: gettyimages-chrisboswell
Categories: Wisconsin, Crops, Corn