Agriculture and Forestry

Saving Soils by Planting Prairie: Benefits of Perennials

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August 12, 2016

“Two hundred years ago, farmers plowed up the prairie because they didn’t consider it valuable. . . or couldn’t eat it. Now we’re asking them to plant it.”

That’s how Lisa Schulte Moore, an Iowa State professor, describes current efforts to promote planting perennials among farmers. Perennial prairie provides a variety of benefits, including reduced soil erosion, lower nutrient runoff, and healthier soils. Perennial root systems are long and last through the year, allowing them to hold soil in place and slow potential runoff. Despite these benefits, many farmers are reluctant to start planting, but interest is growing.

 

Protecting Fertile Soils

Some researchers believe that Iowa farmers will have to plant perennials before long to keep the soil from eroding away completely. Rick Cruse, a researcher at Iowa State, says that the thickness of the topsoil has gone from being 14 inches, 150 years ago, to now only six inches.

Tim Smith, a farmer who has planted three acres of perennial prairie on his farm, expressed concern over the future of Iowa’s soils. “Can we keep going this way for another 150 years? I don’t think so.”

Cruse says that the loss in topsoil is translating to losses in profits for farmers. Adding up the economic losses from soil erosion, he says that, “you quickly surpass a billion dollars of annual lost revenue.”

The perennial prairie is the reason that Iowa has such fertile soil at all, says Schulte Moore. She says that “we’re killing” the thing that has been vital to agricultural production.

 

Nutrient Runoff: Point or Non-Point?

Excess nutrients from chemical fertilizers run off from farms, polluting waterways. This nutrient runoff can cause algal blooms that suffocate aquatic life and create human health problems, especially for infants, when found in drinking water. The Gulf of Mexico “dead zone,” which affects an area larger than Connecticut, forms each summer largely as a result of this nutrient pollution. The dead zone causes big losses for the fishing and tourism industries around the Gulf.

The Des Moines water utility has taken unprecedented steps to fight nutrient runoff by suing three upstate agricultural counties over the pollution in the Raccoon River, a main source of drinking water for residents. Currently, Des Moines Water Works is paying to remove the pollution from upstream at a cost of $1 million each year. As nutrient pollution is expected to increase, the utility also plans to build a new $80 million facility to handle the higher loads.

“We view it as a violation of the Clean Water Act,” said Bill Stowe, Des Moines Water Works’ chief executive and general manager.

Agricultural runoff is currently treated as a non-point source of pollution, which is not regulated in surface water under the Clean Water Act. However, Des Moines Water Works argues that the nutrient pollution from drainage districts is affecting ground water and should be regulated as point-source pollution. Stowe argues, “They're a point-source polluter like a factory or a city stormwater system or a wastewater plant.”

The agricultural counties disagree. John Torbert, executive director of the Iowa Drainage District Association, said, “It would be like suing the highway because cars travel the highway and cause pollution.” The outcome of the lawsuit could have big implications for how the United States regulates agricultural runoff in the future.

 

Progressing with Perennial Prairie

The STRIPS program—Science-based Trials of Row-Crops Integrated with Prairie Strips—promotes strategically planting smaller strips of perennial prairie in with traditional crops. The STRIPS research has shown that converting 10 percent of traditional row crop acreage to perennials can lead to a 95 percent reduction in erosion and an 85 percent reduction in nutrient loss, a huge improvement. Now, the program needs additional funds to incentivize more farmers.

Several federal programs can help farmers establish perennials on their lands. One example is the Biomass Crop Assistance Program (BCAP), which aims to help farmers grow crops to be used for bioenergy. BCAP, a Farm Bill program by USDA, may cover up to 75 percent of the costs of establishing a perennial crop.

Another program is EQIP (Environmental Quality Incentives Program), run through the Natural Resources Conservation Service (NRCS) at USDA. EQIP provides assistance and funding to farmers who implement conservation practices on their lands. Planting perennials is just one conservation practice covered in the program.

Iowa farmer Tim Smith received funding from the NRCS to plant strips of perennials, but he says, “…you go to another county, and it might be a whole different discussion. They say, ‘Do this, and you don’t do that.’ You don’t get a consistent answer in every office.”

At the state level, Iowa has a voluntary program in place aimed at reducing nutrient runoff from farms. For many farmers in the state, keeping efforts voluntary is key. Cedar Rapids Mayor Ron Corbett said, “If we don’t want judges deciding from the bench water policy for Iowa, and we really don’t want the EPA coming in and telling farmers what to do, the best way is to take the initiative on ourselves.”

 

Author: Rebecca Chillrud

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