Back to Leopold Letter Spring 2005
By LAURA MILLER, Newsletter editor
Visitors to the Armstrong Research and Demonstration Farm in southwest Iowa are doing double-takes when they see the farm's new hoop barn.
The open-ended hoop barn has the familiar half-moon profile, created by a white polyvinyl tarp stretched over curved trusses that are attached to fixed side walls. But the structure is a lot bigger than most hoops -- 120 ft. long, 50 ft. wide and 26 ft. from peak to dirt-and-gravel floor. A vent for air circulation runs along the top ridge, and one side wall opens to an outside feed bunk covered by an overhang.
A look inside explains the differences. This hoop barn houses beef cattle - 120 feeder cattle in deep bedded cornstalks - not hogs, farm equipment or hay, the more typical uses for these structures.
It's also the site of a new research project that focuses on alternative production systems for beef. Data will be collected and analyzed over the next three years for a side-by-side comparison of feeding beef cattle at the research farm: in three pens underneath the hoop structure and a conventional open feedlot with a covered shelter.
The Leopold Center provided a $20,000 grant to help pay for construction of the hoop barn, completed in November 2004. And Hoop Group II, a re-design of the team of Iowa State University researchers that the Leopold Center brought together to study swine production in hoop barns, will direct the research.
Other partners include the Iowa Cattlemen's Foundation, the Wallace Foundation that owns the research farm, the U.S. Department of Agriculture, ISU Experiment Station, CoverAll Building Systems that adapted the structure for this project, and 21 southwest Iowa cattle feeders and agribusinesses who made personal donations.
Why the excitement? It's all about the environment.
Environmental benefits
Mark Honeyman is an animal science professor who oversees ISU's research farms and is a long-time proponent of alternative systems. He said hoop barns may be a cost effective way for beef producers to meet a growing number of regulations regarding manure management and treatment of feedlot runoff.
"You don't get rain inside a hoop, so the structure will greatly minimize runoff following a rainstorm," Honeyman said. "Think of it, a feedlot with minimal runoff. That alone could make a hoop barn more economical than conventional open feedlots, but we don't know yet."
Honeyman said they will be monitoring cattle performance and behavior, as well as the environment inside the hoop barn and runoff and soil quality in and around the barn.
"We'll follow the research model we developed when we began to study pigs and hoops in 1997," he added. "At the time, there was work with pigs in hoop barns in Canada, but we don't know of anyone in Iowa or anywhere else using hoops for fed cattle."
Shawn Shouse is an ISU Extension agriculture engineering field specialist at the Armstrong farm. He said the idea for a beef hoop barn has been discussed for several years.
"Environmental challenges are big ones for open feedlots and hoops are noticeably less expensive than other building styles, but we've always wondered if they would work for beef cattle," he said. "This system could provide the greatest advantage for small and midsize beef finishing operations."
The hoop barn opens to the north and south to take advantage of prevailing winds for natural ventilation and to minimize southern sun exposure during the summer. Although the hoop has an enclosure kit for the north end, they decided not to use it the first winter.
"We wanted to see how it would work with just a partial wind break, using bedding bales," Shouse said. "Snow got into the building at time but really wasn't a problem. We're more anxious to see how the animals do in summer months."
Design considerations
The feed bunk that runs along the east wall can be filled from the outside. Under the hoop next to the bunk is a 20-ft. concrete floor that is used when manure is scraped. The rest of the floor is covered with limestone screenings on top of a geotextile fabric.
Shouse said the hoop also presents unique management and labor concerns. Each 40-head pen requires about one large bale of cornstalks every week. The bedding, which absorbs the manure, is scraped from the area in front of the feed bunk to the back of the pens. It's also stockpiled outside and composted for land application later in the season.
He said construction costs were higher than expected but still compare favorably to other systems. He estimates the cost at about $300 per animal space, compared to approximately $500 per animal space for a total confinement system and $150-$200 per animal space for open feedlots. Manure handling for operations under 1,000 head add another $25 to $50 expense per animal space.
Mark Bentley feeds about 200 cattle west of Oakland and is one of the project's individual contributors.
"I really hope it works," Bentley said. "We'd like to expand but we're not sure we could meet all the environmental standards. This system could possibly eliminate some of those concerns."
Honeyman agreed, adding that the project is "a great example of leadership by the Leopold Center. The grant will help put choices on the menu for Iowa producers."
To visit the Armstrong farm, contact beef cattle manager Dallas Maxwell, dallasm@iastate.edu, (712) 769-2402.
About Hoop Group II
The Leopold Center began to explore hoop barns as an alternative production system for swine more than a decade ago. In 1997, the Center organized a team of Iowa State University researchers that became known as the Hoop Group and funded numerous projects conducted by the team.
Although the Center's direct financial support of the team ended in 2002, the Hoop Group has continued its work, in recent years with federal earmark funds acquired with the help of the Leopold Center. Some of the federal funds are being used for the beef cattle hoop barn project.
Working on the beef hoop project are:
Mark Honeyman, animal science
Steven Lonergan, animal science
Shawn Shouse, ISU Extension agricultural engineering field specialist
Back to Leopold Letter Spring 2005