Home-buyers of tomorrow could find themselves walking across floors made from manure. Researchers at Michigan State University and the U.S. Department of Agriculture insist it's no cow pie in the sky dream. They say that fiber from processed and sterilized cow manure could take the place of sawdust in making fiberboard, which is used to make everything from furniture to flooring to store shelves.
And the resulting product smells just fine.
The researchers hope it could be part of the solution to the nation's 1.5-trillion- to 2-trillion pound annual farm waste disposal problem.
The concept has its skeptics.
"Is this something you're going to bring into the house?" asked Steve Fowler, an economist with the Composite Panel Association, a fiberboard-makers trade group based in Gaithersburg, Md.
Traditionally, farmers put manure to use by spreading it in their field as a natural fertilizer. But as dairy farms and other livestock operations have gotten larger and more specialized, they can find themselves with too little land for the manure they produce.
Furthermore, people who move into what used to be rural areas often fail to appreciate the odors than can come from manure.
"Farmers are having to put more and more money into dealing with manure," said Tim Zauche, a chemistry professor at the University of Wisconsin-Platteville. "This is a huge cost to farmers."
A dairy farm can spend $200 per cow per year to handle its manure, Zauche said.
Under pressure from regulators and the public, more large livestock operations are installing expensive manure treatment systems known as anaerobic digesters.
The digesters use heat to deodorize and sterilize manure, while capturing and using the methane gas it produces to generate electricity. The systems also separate phosphorus-laden liquid fertilizer from semisolid plant residue.
The solids have some known uses, such as for animal bedding and potting soil. Agricultural scientists would like to find more.
"We really need to think outside the box on what uses for manure are," said Wendy Powers, a professor of agriculture at Michigan State University.
Scientists at Michigan State in East Lansing and at the USDA's Forest Products Laboratory in Madison, Wis., are conducting tests on various types of fiberboard made with the "digester solids."
As with the wood-based original, the manure-based product is made by combining fibers with a chemical resin, then subjecting the mixture to heat and pressure.
So far, fiberboard made with digester solids seems to match or beat the quality of wood-based products.
"It appears that the fibers interlock with each other better than wood," said Charles Gould at Michigan State's College of Agriculture and Natural Resources. "We end up with, I think, a superior material."
Gould and Laurent Matuana, a forestry professor at Michigan State, are working on a final report on their pilot study of manure-based fiberboard, funded by a $5,000 grant from the Michigan Biomas Energy Program.
A draft of the report concludes that fiberboard panels made with processed manure "performed very well in mechanical tests, in many cases meeting or exceeding the standard requirements for particleboard."
In Wisconsin, the USDA forest products lab has just begun an 18-month, $30,000 study that will test the strength and endurance of the manure-based fiberboard and examine the economic practicality of using digested fiber to make building products.
One good thing about the manure-based fiber is cost, said Zauche, who is working as a consultant on the USDA lab's research project.
"Its cheaper than dirt," he said.
Whether that's enough to overcome the public's squeamishness about using a manure byproduct as a building product remains to be seen, said Craig Adair, spokesman for APA — The Engineered Wood Association, a Tacoma, Wash.-based group that represents the plywood industry.
"If nobody in industry has an interest, it will die," Adair said.