Mission impossible: Reinvent this field
Don Biehle waited a long time to convert a piece of land the Southeastern Purdue Agricultural Center acquired a few years ago into useful land. The SEPAC superintendent planned to install pattern drainage in zones with water control structures, establish wetland habitat around the irregular borders of the wooded field and restore a wetland. But the project scheduled for August 2009 was scrubbed when Mother Nature dumped several inches of rain on the farm near Butlerville.
Fast-forward to this July. SEPAC and the Indiana Land Improvement Contractors Association planned a field day to demonstrate various tiling options. This time rains skirted SEPAC, letting workers get down to business under good conditions. In two days they laid the groundwork for a field and wildlife setting that can be used either for farmland or agronomic and natural resource-related research. The project also serves as a model of how a field can be improved.
• SEPAC field is converted to productive farmland.
• Thirty-foot tile spacing, while not typical, is an option.
• Turning irregular edges into wildlife habitat and wetlands adds value.
“We’ve done similar field days and projects at the Davis Ag Center near Farmland and the Northeast Purdue Ag Center near Columbia City,” says Steve Hawkins, assistant director of Purdue University’s outlying farms. “We bid the projects out. With LICA getting the bids and agreeing to do it as field days, it’s a win-win for everyone. Biehle just had to wait an extra year for his turn.”
“The field we wanted to improve is nearly level and consists of mostly level, poorly drained Clermont soil,” Biehle explains. Natives know it as gray flats. It was once thought impossible to drain, but Eileen Kadivko and other researchers have a 26-year-old drainage project under way that proves it can be drained — if there are outlets.
“We have plenty of outlets in this field,” Biehle says. “We’re constructing a wetland on one side, once it’s dry enough to work there. It will be an outlet, too. There will be a water control structure tied to it so we can regulate water levels in the wetland.”
One problem with the irregular, tree-lined borders was that it wasn’t economical to grow crops there, between trees shading and sucking up moisture, and wildlife nibbling crops. “We elected to reconstruct the field with regular borders for tiling purposes,” Biehle says. “That’s what we’ll farm. We weren’t making money on the outsides anyway. We’re converting about 8 acres from crops to wildlife habitat.”
Biehle and his crew chose 30-foot spacing for laterals feeding a main. “The recommendation wouldn’t be for spacing that close,” he observes. “But it matches up well with equipment size in case we do research here.”
Various types of trenchers operated in the field. Some still use lasers to get the grade correct. Others operate off of RTK GPS and autoguidance. In either case, the laterals still have to be connected to the main by hand.
Various contractors also demonstrated options for closing the trench. Clark Excavating, New Castle, used a rear-mounted tool to roll dirt back in on both sides. Then a separate machine finished bringing those mounds of dirt together over the tile line.
Laying the patterned system out in zones gives Biehle and his crew flexibility in how to manage the field. Three of the zones are connected to water control structures. That allows them to raise or lower the water level. If they want to keep nitrates out of tile lines this winter, they can close off flow.
“We’re not totally sure how we’re going to utilize this field yet,” Biehle says. “But it certainly is an improvement. The acres we farm will be more productive, and we have flexibility to measure tile flow, or do other studies here.”
SEPAC tile design plan
This article published in the September, 2010 edition of INDIANA PRAIRIE FARMER.