12.13: A Case Study, Darrell Parks

Manhattan, Kansas

Even if Darrell Parks didn’t like working with hogs, he would still raise them on his 275-acre farm in the Flint Hills of Kansas, if only for the manure that makes up a key part of his soil fertility program. Each year, Parks’ farm raises and finishes about 500 hogs from 40 sows, while also producing corn, milo, wheat, soybeans and alfalfa. He sells his hogs to the Organic Valley cooperative and as pork cuts at a local farmers’ market.

Parks spot-treats his land with hog manure to help areas needing extra fertility. He likes how targeting problem areas with thicker applications of manure corrects soil micronutrient deficiencies. “Manure from the hogs doesn't supply all my fertility needs, but with cover crops and organic fertility additions that are more available now I have been able to maintain decent yields,” says Parks, who received a grant from USDA’s Sustainable Agriculture Research and Education (SARE) program to hone his use of manure on cropland. He was successful in that endeavor, and his cropland has been certified organic since 1996.

Parks’ crops are raised mainly in two rotations. In one rotation, alfalfa is grown for three years, followed by a year each of corn and soybeans before returning to alfalfa. In the other, he plants Austrian winter peas in the late fall following wheat harvest. The peas, incorporated in the spring, are followed with a cash crop of milo or soybeans prior to a fall- or spring-planted wheat crop.

To ensure a sufficient nutrient supply for his wheat crops, Parks typically treats his wheat fields with liquid manure at a rate of approximately 660 gallons per acre. He collects this manure in a concrete pit adjacent to a building where sows are housed for brief periods during breeding or when being sold. The liquid manure, for which he does not typically obtain a nutrient analysis, “catches a lot of rainfall and is fairly dilute—[essentially] high-powered water,” he says. “I avoid wet conditions when spreading and try to hit the wheat in March or April during a dry period on a still day, before [the wheat] is too big.”

Parks sometimes lets older sows out to pasture on some of his fields, where they spread their own manure. He cautions, however, against pasturing young pigs on alfalfa. “You’d think they’d balance their ration better,” he says, “but they don’t—they overeat.”

For most of their lives, Parks’ hogs are raised on half of a 10-acre field. He plants the remaining five acres to corn. Once the corn is harvested, he moves the hogs and their pens over to the “clean ground” of corn stubble. “Going back and forth like this seems to work well in keeping the worms down,” he says. And he notes that the 50–60 pounds of N per acre put down with the hogs’ manure helps grow “some pretty good corn” in that field each year.

Parks notes that his tillage regime, on which he is dependent for weed control in his organic system, makes maintaining and improving his soil organic matter content especially challenging. That’s why he remains committed to integrating the use of both animal and “green” manures on his farm.

Striving for economic sustainability, Parks is constantly weighing the pros and cons of becoming more self-sufficient by raising his own feed for the hogs versus taking advantage of the price premiums for organic grains.

“It’s a hard decision,” he says. “Right now, if I cut down on hogs, maybe it would be better economically. But if I get out [of raising hogs entirely], it’s not easy to get back in.”

For now, he is betting that over the longer term, he’s better off keeping his hogs. “A lot of people don’t like the idea of how pigs are raised” within a conventional operation, he says. “We’re meeting [the demand of] a niche market in its infancy that is sure to grow.”