LEXINGTON n To Tim Lindenbaum, the 250-acre rolling, wooded farm along the Mackinaw River represents one big Petri dish.
The Lexington farmer and The Nature Conservancy outreach coordinator hopes the experiment may one day yield solutions to soil erosion and water runoff which benefit the world.
While the goal may seem lofty, Lindenbaum and Maria Lemke, Nature Conservancy aquatic ecologist, believe it's attainable. Their work on the Franklin demonstration farm, as well as a paired wetlands study near Colfax and Anchor, aims to determine which land and water conservation practices along the Mackinaw River work best in terms of economics and public benefit.
"The Nature Conservancy doesn't own any land. We partner with private landowners. We show farmers how to use existing programs for funding and technical assistance," said Lemke, based in Petersburg. "Up until now, there's not been a lot of evaluation of processes. It's expensive to monitor, and it takes years to do. You also need continued funding."
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In the early 1990s, The Nature Conservancy became interested in the Mackinaw River and the 750,000 acres of farmland which drain into it. The nonprofit, natural resource preservation group saw the Mackinaw as a jewel in Illinois' surface water crown.
Lemke said the river system contains 25 percent of the state's highest quality stream segments. It also provides habitat to highly diverse animal and plant populations. Several endangered species thrive in the river system.
Because the watershed draining into the river contains so much land, The Nature Conservancy officials decided to focus on one, small portion to find the most effective water and soil quality practices. That work gets done on the experimental farm and the Colfax/Anchor study encompassing 20,000 acres.
The John Franklin family of Lexington became a partner with The Nature Conservancy three years ago. Lindenbaum rents the farm, growing corn and soybeans on a portion of the land. Most of the demonstration farm contains wooded and grassed acreage along the river.
Last fall, a series of experimental, tile-fed wetlands, along with floodplain wetlands draining surface and tile water, were built with cost-share funds provided through the federal Environmental Quality Incentives Program and Conservation Reserve Program.
"A big chunk of the work was paid for n probably 60 to 75 percent n through the programs. They have a unique situation in trying to tie in soil, water, animals and plants," said Kent Bohnhoff, McLean County Natural Resources Conservation Service district conservationist. "They had different objectives than most producers. They looked at the whole situation rather than just cropland. For the last 100 years, we've tried to drain wet areas and make them productive."
Bohnhoff and his staff helped design most of the demonstration farm practices. They further signed a contract with the Franklins and helped secure funding to complete construction work. He noted the Franklins receive annual rental payment for CRP acreage taken out of crop production.
The two experimental, upland wetlands each contain three sections. The first drains 3 percent of the land draining into the farm. The second drains 6 percent, and the third drains 9 percent.
"We're testing how large a wetland needs to be in order to be affordable and effective. We don't want to build wetlands larger than we need," said Lemke, noting wetlands provide areas for runoff water to settle and deposit soil sediment and nutrients before entering rivers, streams and lakes.
A monitoring system accompanies the experimental wetlands. Water samples get automatically collected at timed intervals or according to volume of water flowing through the monitoring system. Lindenbaum and Lemke will eventually know how much water enters and leaves the wetland in addition to the amount of nutrients and soil sediment contained in the water. The duo hopes to have concrete data in about five years.
"Farmers want to see how something works. That's the great part of the demonstration farm. We can show them how to farm around a wetland. We can help them sign up for programs to help fund the practices," said Lindenbaum, who plans to invite the public to the farm later this spring or summer.
A host of data concerning effectiveness of grass waterways, buffer strips along the river and conservation tillage practices in improving soil and water quality already exists. Lemke and Lindenbaum collected data from 2000 to 2005 from the paired wetlands study on Bray and Frog Alley creeks funded by the W.R. Kellogg Foundation.
Lindenbaum only contacted farmland owners in the Bray Creek wetland. Frog Alley served as a control wetland where no new practices were encouraged. Lindenbaum said landowners decided to increase their conservation efforts based on economics. Many of the landowners now receive government payment for using conservation practices.
Grass waterway acreage surrounding Bray Creek increased from 5 acres to 30 acres, while buffer strip acreage increased from 20 acres to 120 acres. Strip-till acreage increased from 2 percent to 12 percent. The practice involves planting crops in narrow, tilled strips while the surrounding soil remains protected from erosion by crop residue.
The increase in those practices prompted nitrate levels to drop 20 to 30 percent lower in Bray Creek compared to Frog Alley. However, Lemke said nitrate levels still sometimes exceeded 10 parts per million. Environmental Protection Agency standards require drinking water to contain less than 10 ppm.
That finding led Lemke and Lindenbaum to Phase II. In addition to studying wetland size and function, the extended project involves a subirrigation system installed last fall on Larry Durbin's farm near Colfax. The system involves 3-inch tile laid every 15 feet.
Excess water drains into a holding pond. A 4-cylinder, 50-horsepower diesel pump can push water from the holding pond back into the field when dry soil conditions develop. If the holding pond would overflow because of torrential rains, it drains into a wetland before reaching streams.
"We need to know which practices work best economically and environmentally," said Lemke. "Then we can scale this up to the entire Mackinaw watershed, and to the Illinois River and the upper Mississippi River. We also have partners interested in Brazil and China. These practices are not only good for the individual landowners but also for the surrounding communities. They may be able to save money on dredging costs as well as water treatment."
The ultimate goal remains reducing the nitrogen runoff by 30 percent to the Gulf of Mexico. Scientists believe runoff of agrichemicals, and nitrogen specifically, contributes to hypoxia, or the Gulf's dead zone. Hypoxia is an oxygen deficiency which can contribute to death of marine life.
"There's no question we can make a difference worldwide. One challenge of environmental/farm programs is that we don't actually know if they're making a difference," said Michael Reuter, Nature Conservancy Great Rivers Partnership director. "These are global decisions at play. We intend to arm decision makers throughout the world with good information."
