WASHINGTON – It’s rural America’s version of keeping up with the Joneses.
There’s a 80-acre section of farmland on the east side of Route 136 in central Illinois that dramatically illustrates the benefits of systematic farm drainage every time it rains. An unmistakable line is drawn along the property border with healthy crops on one side and large pools of standing water and severely damaged crops on the other.
“The neighbors are starting to notice,” said Dave Williamson, co-owner of Williamson Drainage of Bloomington, Ill. “The practice of systematically draining a farm of that size is starting to catch on more in this part of the country. It’s been more prevalent in other parts of the Midwest, but now people are starting to see results that go beyond just random site drainage.”
Spreading the news. The Plastics Pipe Institute is hoping to spread that message: Drainage and agriculture are inseparable sciences.
The institute has funded a published report that details hundreds of years of documented evidence that controlled agricultural drainage is vital to meet the current and future needs of our rapidly expanding population. It has posted the White Paper on its Web site at www.plasticpipe.org and also at www.cppa-info.org.
“This project is a compilation of virtually every published report on the effects of controlled agricultural drainage in the last half-century,” said Rich Gottwald, the institute’s executive director. “The result is a document addressing issues that will determine the sustainability of agriculture now and in the future.”
The white paper was written by Jeff Healy, president of Banning Engineering in Plainfield, Ind. Along with an extensive look at historical drainage practices, Healy identifies the main effects of drainage:
* Improvement of soil aeration to allow deeper and more extensive root development;
* Maintaining soil moisture at a controlled level means movement of farm vehicles over the land surface is not delayed due to the result of extreme weather conditions (consistent trafficability);
* Maintaining optimal soil temperature;
* Eliminating toxic substances and disease;
* Prevention of soil erosion and flooding;
* Improving crop yields;
* Increased water supply; and
* Salinity control.
Tale of the tape. In Illinois, Williamson credits the recent surge in popularity of yield monitors on combines for the recent emphasis on systematically draining farms of all sizes. One of his customers was shocked when he noticed that average corn yields on sections with the best soils were 60 bushels per acre lower than yields on lesser soils on his property.
“Our customer was getting bushel per acre averages of 174 last year on that farm, and he believed that to be a good crop yield,” Williamson said. “But now with yield maps and monitors, we can see that the A soils were contributing 146 of that and the B soils were yielding about 206.”
After eliminating factors such as stand pressure, weed pressure, fertility and insects, Williamson concluded that the “better” land was being improperly drained and recommended a systematic drainage system.
“You can get decent yields on undrained fields,” Williamson said. “But we don’t realize how much capacity our soil really has. A lot of farmers can do a lot better.”
Critics. Williamson and the institute both acknowledge the arguments of agriculture drainage critics. One point that continually surfaces is the nitrogen build-up into nitrites after an extended dry period. Some theorize that a heavy rain can flush those nitrites into the tile water.
Healy’s white paper offers a solution. Design new subsurface drainage systems or retrofit existing drainage systems to manage soil water and water table levels through controlled drainage or sub irrigation, lowering concentration of nitrate-N in shallow ground water. The cost of retrofitting existing systems for sub irrigation can be compared to the benefit of increased yields.
