Is subsoiling a part of your farm routine? Do you swear by it or swear at the thought of it? While the ideal time to subsoil is after the fall harvest, delays sometimes occur. Late harvests or inclement weather can push subsoiling back to January. Well, it is January, so the question remains: will you be subsoiling or not?
Depending on where you live and the type of soil you have, subsoiling with a low disturbance tool can benefit you greatly. For example, if you have soil that is compacted by heavy machinery or naturally compacts on its own (such as silty or clay loam soil), subsoiling at 12-18 inches deep (as oppposed to 6-8 inches deep) will allow aeration of roots and more potential for water movement. This can also mean more nutrients and minerals accessed and available for optimum seed growth, improving crop yields.
Subsoiling can help alleviate the formation of a tight layer of soil known as a plow pan. Having soil of this consistency prevents water from accessing deep roots. The result is top soil that appears wet when the soil beneath the plow pan is actually dry and thirsting for moisture. Sideways root growth can occur due to this type of compaction, resulting in damage and premature crop death and/or failure of crops to thrive.
Much like everything else, subsoiling has both advantages and disadvantages. Subsoiling is environmentally friendly because it allows farmers to utilize no-till thus conserving water. It also improves soil quality and reduces the compaction that could lead to tunneling roots in addition to stopping the preventing of water from reaching depths necessary for optimum growth. These benefits do not come without work, however, and subsoiling is a task that requires the application of horsepower to complete, more so than chisel plowing or no-till. This raises the cost of production but that can be taken in stride at the end of the day when your yield is greater. Yield increases of 3 bu/acre on Sharkey clay and 25.2bu/acre on Earle clay have been reported.
The key to knowing whether or not to subsoil lies in knowing your soil. Certain types of soil will benefit more than others, and it is up to you to decide if your soil is one of them. If you have compaction issues, it might be worthwhile to attempt subsoiling in moderation to see if your yield increases or decreases before you undertake the time and expense of subsoiling of your entire property. You may find yourself pleasantly surprised by the results or you may be glad you only did a portion of your property, giving you a learning experience which can prove invaluable with either outcome.