Across the country, farmers are busy with spring preparations. If they’re not planting yet, they’re getting ready to by tuning up the planter, swapping out parts and installing tile. Many farmers use tillage to dry out the ground in the spring, but obviously that’s not a go-to practice for no-tillers.
Tile drainage has become a popular option, despite the cost of installing it, which can be in then hundreds of dollars per acre. The use of tile is associated with improved drainage, reduced soil erosion and higher yields but it’s also sometimes blamed for higher levels of nutrient runoff in waterways.
A new study by Karen Ryberg, a researcher at the U.S. Geological Survey, shows it may also be responsible for higher waterway concentrations of the herbicide atrazine and the compound it breaks down into, deethylatrazine (DEA).
Regulations in the 1990s called for lower application rates of atrazine on crops and use of the herbicide has decreased over time, though it is still the second-most applied herbicide in the U.S., after glyphosate, according to Ryberg.
Ryberg’s research turned up an unexpected find. Since those new regulations went into effect, levels of DEA in waterways have actually gone up instead of mirroring the decreased usage of atrazine.
The research shows that DEA is more soluble in water than atrazine, meaning it moves more easily through ground water and into streams. An increase in the use of tile facilitates that movement from field to stream, which can explain the rise in DEA levels in waterways.
In a summary of the study, the American Society of Agronomy concludes that “there may be more challenges with atrazine levels in the future. As farmers anticipate climate change and wetter field conditions, more tile drains may be needed in order to grow crops in adequate soil conditions.”
Other options exist for dealing with excess moisture, including saturated riparian buffers and wetlands, which can filter runoff, and controlled drainage systems, which can help manage the water table on the farm, reducing runoff into local waterways. These systems are especially useful for those areas that are wet during certain times during the year but dry during others.
Managing the water table could be a very powerful alternative to the flood/drought cycle experienced in many areas.
If the wet weather of the last couple of years persists, farmers will be faced with a greater need for efficient drainage as well as increased pressure to reduce water-quality impacts to local watersheds.
Installing tile is a first step, but the implications of stopping there need to be considered. Yes, there are costs involved in beefing up a drainage system, but those costs may pay for themselves in more consistent yields, reduced soil erosion and healthier waterways.
No-tillers are certainly ahead of the game with tiling and other solutions like buffer strips, though in tough economic times like we’re in now, it may seem like an unnecessary luxury.
What’s your approach to the drainage game? Are you adding tile to your operation, or even taking the next step to incorporate riparian buffers or controlled drainage? Tell us about it in the comments section below.