IOWA CITY, Iowa — Two Iowa State University (ISU) extension specialists have been studying the possible economic feasibility of growing double-crop field peas as the state’s third alternative crop to be used for swine rations.

“Farmers are continually searching for a third crop to complement the corn-soybean rotation,” wrote Johnson County-based Crop Specialist Jim Fawcett and Washington County-based Swine Specialist Tom Miller about their preliminary findings in designated research fields in southeast Iowa.

“Field peas can be substituted for most of the soybean meal in swine rations and is more economical than soybean meal, so there is a huge potential market for field peas in Iowa,” Fawcett and Miller wrote.

The two ISU extension specialists also concluded that since field peas are a short season crop, which can be fed directly on the farm, they would make double cropping a real possibility and yield potential profits.

“There have been some recent reports out of Illinois of some success in planting field peas in the summer after a winter wheat harvest,” Fawcett and Miller added.

Funded by a 2-year, $50,000 special ecology initiative project grant by ISU’s Leopold Center for Sustainable Agriculture, a three-year, $100,000 grant through Sustainable Agriculture and Research Education (SARE) in Washington, D.C. and a USDA grant to supplement the Leopold Center’s three-year funding, Fawcett and Miller would be overseeing the project through 2008.

Fawcett and Miller said their research consisted of a small-plot crop rotation trial located on ISU’s Research Farm in nearby Crawfordsville, Iowa, which consisted of three crop rotations of corn-soybean, cornfield peas and soybeans and corn-soybean-winter wheat and field peas, and a large-scale, double-cropping trial located on newly purchased land.

In addition, two field pea varieties, Eclipse and WFP-0097, were grown in rotation 2, as well as three field pea varieties, Eclipse, WFP-0097 and Admiral, and three pea planting dates (July 11, 18 and 28) were used in rotation 3, with all treatments replicated four times in a randomized, complete block design, Fawcett and Miller said in their report.

According to Fawcett and Miller, who have been working with three area farmers on test plots at the Crawfordsville Research Farm, the project currently includes winter peas, followed by soybean and spring peas planted after wheat.

“We had a preliminary trial with summer planted peas after winter wheat in 2004,” Fawcett said. “The peas were planted too late and did not mature before the fall frost. More extensive trials were conducted in 2005 with spring peas, followed by double-cropped soybeans and summer planted peas after winter wheat. A large-scale swine feeding trial was also recently completed.”

Fawcett said the idea for field peas possibly becoming an alternative third crop in Iowa came about because there was interest among Washington County pork producers in feeding peas in place of soybean meal because it is cheaper and does not have to be processed off of the farm.

“Shaun Greiner in Washington County and Brad Dvorsky in Johnson County planted about 15 acres each of peas in July following a winter wheat harvest,” Fawcett said. “(But) yields were poor because of the heat and drought in the summer of 2005.”

In fact, Greiner initiated the concept for the project two years ago, Miller said.

“Jim and I were approached in the spring/summer of 2004 about the possibility if this would be a feasible crop for Iowa,” he said. “We applied for a mini-SARE grant to look at producing peas following wheat in a double-crop situation.”

In a large-scale trial, Fawcett said 75 acres of peas were planted in mid-March 2005 in Louisa County, harvested in late June, followed by double-cropped soybeans planted on July 1. The pea yields also ranged from about 30 to 55 bushels per acre, depending on soil type and soil fertility, and the double-cropped soybeans yielded 26 bushels per acre.

Moreover, yields of summer-planted peas averaged about 14 bushels per acre in small plots on the Crawfordsville in 2005. Fawcett said results of the feeding trial haven’t been summarized, but the first feeding trial compared rations containing two different pea varieties to the standard ration containing soybean meal.

Fawcett said winter peas were also planted late last fall at the Crawfordsville Research Farm to see if they had potential in Iowa.

“At the research farm, three planting dates and three varieties of summer planted peas (after winter wheat) are being investigated,” he said. “Yields of the spring planted peas were 52 bushels per acre in the small plots, but the double cropped soybeans had a poor yield, partly because of harvest problems with the combine.”

More recently, Miller said he and Fawcett completed a feed trial in Washington County where peas raised in southeast Iowa were fed in a 1,200 head grow finish building.

“Pigs were divided into six groups with two different varieties of peas fed as well as a corn-soy diet for the control,” he said. “Results are currently being tabulated.”

The historic Amana Farms in Iowa County will also plant spring peas this year as part of the trial, Fawcett added.

This farm news was published in the March 15, 2006 issue of Farm World.