How Prairie Plants Help Restore Farmland Soil
The world’s soil is in trouble, even in the fertile Midwest. Some experts warn that if degradation continues unchecked, topsoil could be gone in 60 years. That has implications for agriculture and the broader environment.
Farmers feel the pressure of feeding a growing global population and protecting the soil necessary to do that—all while operating a viable business. Their interests and needs don’t always align with the research endeavors of ecologists focused on biodiversity. But a project in Iowa brought Iowa State University ecologist Lisa Schulte Moore and cattleman Seth Watkins together.
Schulte Moore and her colleagues had been experimenting with how to restore native prairie landscapes in a state where the dominant land use today is agriculture.
“Are there ways that we can take advantage of this historically predominant, native ecosystem of Iowa, not only to benefit our natural areas but to benefit agriculture itself?” Schulte Moore asked herself. To find out, she worked with the Neal Smith National Wildlife Refuge in Prairie City, Iowa, and planted strips of prairie alongside crops. The project is called “Science-based Trials of Row Crops Integrated with Prairie Strips,” or STRIPs.
In the experiments, the tall grasses with their deep roots did just what the researchers hoped.
“I'm a nerdy scientist, but I've worked on lots of different projects in lots of different areas,” Schulte Moore said. “The data that we have associated with the STRIPS experiment, from a scientific perspective, I consider it absolutely beautiful.”
Nitrogen runoff, phosphorus runoff and sediment loss all went down by 90 percent in the trials. Those are three of the biggest scourges for farmers. The research team felt they had something that at least some farmers would be willing to try.
“They want to do it because they can recognize that they need to do more to preserve their own soils, which is the source of their profitability,” Schulte Moore said. Some also share the ecologists’ interest in seeing more birds and insects on the land.
When Schulte Moore went looking for some farmers to plant prairie strips, Doug Davenport, a district conservationist for the Natural Resources Conservation Service in southwest Iowa, thought of Watkins.
“I’ve worked with him for years and he’s the kind of person that would like to try new things and give it a shot,” Davenport said.
Last winter, Schulte Moore and some other members of the STRIPs team visited one of Watkins’ fields in Taylor County, Iowa, and helped him survey the area and determine the best position and size for the five prairie strips that he put in early this summer.
Watkins already had a few acres of prairie on one of his pastures and said he’d seen the value of mixed tall grasses and flowers. He credits them with clearing a pond that had become cloudy from sediment and likely had high nutrient levels as well. When he removed the cedar trees and scrub brush from the patch of prairie, the native grasses took off. He fenced the now-clear pond and began piping clean drinking water from it to his cattle.
“Cattle that drink clean water, their calves weigh about 50 pounds more at weaning,” Watkins said, “than cattle that are just wandering right out into a pond and mucking it up.”
Watkins expects the new prairie strips to take about three years to fully establish themselves and overtake the weeds that are currently growing on that ground. He said adding prairie strips to his existing conservation measures, which include waterways and wetlands, will further his plans for attracting more wildlife and waterfowl. At the clear pond, Watkins knelt down to identify frogs in the water.
“When we start working on these projects, this is what we’re after,” he said, standing and gesturing widely at the landscape and noting the birds and butterflies. “It goes back to that theory of making people start to recognize our natural resources as an asset.”
Watkins said he finds too often the natural landscape drops from people’s minds as they focus on gaining as much profit as possible from cultivating it.
Throughout his neighborhood, Watkins pointed to straight rows of bright green corn cascading down steep hills. The vista saddens him. In the past few years, he said he’s watched many farmers sell their cattle and convert pastureland to more lucrative row crops.
“I’ll be the first to admit, I don’t have nearly the profit per acre right now that a lot of my neighbors have,” Watkins said. “I will lay odds that over 20 years or 50 years, I can beat them. That’s my thinking. And I know that, unfortunately, long-term thinking is not the norm any more.”
But like many farmers, Watkins is mindful of the projected need to feed 9 billion people by 2050. That will be impossible without soil. On his farm, swaths of prairie may be part of the solution.
This is the first of a two-part report on innovative ways to revive the soil. Click here to see part one on how grazing practices are used to improve soil.