Farming is rooted in dirt, you might say, but sometimes the humble material from which life springs is overlooked as producers, researchers and consumers focus on other aspects of agriculture. Among an increasing number of farmers and ranchers, however, soil health is gaining renewed attention.
A Fresh Look at Old Practices
At Square Peg Farm near Forest Grove, Chris Roehm and his wife, Amy Benson, raise certified organic lettuce, peas, spinach, tomatoes, potatoes, peppers, onions and squash. They also raise a few hogs, but are transitioning to beef cattle.
Roehm worked as an engineer before deciding in 2003 to make a go of the 40-acre family farm. He and his wife follow three primary practices to ensure soil health: cover cropping, rotational grazing by the hogs and cattle, and rotational vegetable plantings.
“The main reason I’m concerned about soil health is because it makes it a lot easier to grow good vegetables,” Roehm says. “With healthy soil, you have less compaction, less insect pressure, less weed pressure and better tasting vegetables.”
The couple typically grows annual vegetables on a 5-acre section of the property for three years, then plants it with cover crops. The former veggie area becomes grazing land for the hogs or cattle for four or five years, while another 5-acre parcel hosts the vegetable production. Roehm says the method works well and he is “definitely sold on it.”
“It’s definitely not something we invented,” he says. “To a large extent it’s an old-school approach.” Many Oregon farms have been using these fundamental techniques for generations. Oregon produces many of the cover crop seeds that are used across the country.
“I do think once you start doing practices like this with an eye to improving soil health, it leads you down the road of pursuing that goal more completely,” Roehm says.
Managing for Healthy Soils
“We don’t call it dirt, that’s a soil scientist joke,” says Cory Owens, a USDA Natural Resources Conservation Service (NRCS) employee in Portland. Owens is the agency’s state soil scientist for Oregon.
The NRCS was born in the aftermath of the drought and erosion of the Dust Bowl in the 1930s. Since then, NRCS has worked with farmers, ranchers and other landowners on conservation projects. In 2012 and 2013, the NRCS launched a national soil health effort, Owens says.
With it came growing recognition of soil’s role in life itself. Soil cleans water and cycles nutrients. As an “engineering medium,” it holds up houses and provides a place for plants to grow, Owens notes.
In Oregon, soil classifications are also a primary factor in land-use decisions and preventing urban sprawl. In general, state law steers commercial and residential development away from prime supports the state’s vineyards, Christmas tree farms and more. Owens says current perspectives and management practices align with two primary goals: feed and protect the soil.
To feed the soil, remember “diversity above for diversity below,” she says, and “keep a living root year round.” Soil is a living organism, she says, and needs “robust and diverse” vegetation present to stay healthy.
To protect the soil, keep it covered and minimize disturbance, she adds. Cover crops are good for the first, while such things as the amount of livestock grazing and “mindful tillage” take care of the second.
“Soil is an ecosystem in its own right,” Owens says. “Treat it as an ecosystem. As a land manager, you are in control of that structure.”