Any form of tillage and cover crops seems to be a contradiction at first glance, but strip-tillage paired with cover crops could have potential to help farmers improve water and nutrient management to increase both yields and profitability.
This is especially true for full tillage producers interested in seeking the benefits of cover crops, without sacrificing some of the flexibility created by spring tillage to create a suitable seedbed prepared as soon as possible.
Although Southern Illinois topography is generally too rolling to utilize strip-tillage without concern for increasing erosion, the strategy of precision planted cover crops seem to have a good potential fit with strip-tillage on flatter regions of the state where nutrient management issues related to nitrogen (N) loss through drainage tile is a concern.
The term “nutrient management” often spurs attention to plant use efficiency related to applied fertilizer inputs. However, it is important to remember that applied fertilizer is just part of the equation, especially where N is concerned, so it is important to consider the complete nutrient cycle across the rotation to make the best production decisions.
“The term “nutrient management” often spurs attention to plant use efficiency related to applied fertilizer inputs. However, it is important to remember that applied fertilizer is just part of the equation, especially where N is concerned, so consider the complete nutrient cycle across the rotation to make the best production decisions…”
And that could lead to another opportunity with cover crops to add N to the system when needed and also to hold excess N, subject to loss after the summer crops are harvested. Although N loss is commonly attributed to excess fertilizer application (which is possible), recent research by Lowell Gentry, principal ag research specialist at the University of Illinois, funded by the Nutrient Research and Education Council (NREC) has found that tile N loss is sometimes greater following soybeans (where no N fertilizer was applied) than corn.
This is due to the low carbon-nitrogen ratio in the soybean stubble that breaks down fairly quickly releasing plant nutrients not removed in the seed at harvest. Mineralization is also a contributing factor to N loss and warmer winters are conducive to this being a great contributing factor to overall N loss.
So, if we have the potential to lose N from our fields that was not applied as a fertilizer input, how do we capitalize on that to keep it in play for the cash crop? Enter cover crops.
While length of growing season, winter weather conditions and other factors have a great influence on the cover crop options available in a given area, there are options in about every case that would add value to a cropping system, and used in conjunction with strip-tillage, where appropriate, would seem to hold potential for increasing overall efficiency in many cases.