By Blake Jackson
While recent rains improved soil moisture for Pennsylvania corn planting, it also raises concerns about sidewall compaction. This compaction, caused by planters in moist clay soils, hinders root development and can hurt yields.
Corn, planted deeper than soybeans, suffers more due to needing more soil movement by openers. A simple "ball test" can indicate compaction risk: moist soil that easily forms a ball is susceptible.
Previously compacted soil from equipment traffic further increases the risk. Farmers might be tempted to increase downpressure on planters in such cases, but this worsens compaction.
Corn's initial root system is most affected. Compacted sidewalls prevent these roots from branching, creating a weak "2D" root system. This is especially damaging during dry periods, when the compacted soil becomes very hard for roots to penetrate.
While crown roots developing later can somewhat compensate, early growth suffers, potentially reducing yields and increasing pest/disease susceptibility. Stunted plants, drought sensitivity, and nutrient deficiencies are some consequences.
Planting at the optimal moisture level is key to reducing compaction. Healthy soil with good tilth, achieved through reduced tillage, increased organic matter, and cover crops, also helps.
Machinery adjustments like reducing downpressure on planter wheels and using spoked closing wheels to break up compacted sidewalls can further mitigate the risk.
Photo Credit: istock-chas53
Categories: Pennsylvania, Crops, Corn