Bunker silos covered with plastic and tires could soon be a thing of the past. In their place could be an edible cover currently under investigation at the University of Illinois.

Although the first formula didn’t meet expectations, a new modified formula looks promising. The cover— a combination of salt, ground wheat and tap water sealed with wax—protects the silage from spoilage and is easy to apply.

When fed to heifers at a rate of 2.5 percent total diet dry matter, it did not affect intake, says Larry Berger, one of the study’s authors. “The animals consumed it readily,” he adds. Although more work is needed before this technique can be applied on-farm, the use of an edible cover may be cost-effective. Berger estimates the net cost to be 10 to 12 cents per square foot of silage for the ingredients. The other added benefit of an edible cover is that it eliminates the need to dispose of the used plastic.