A layer of wood mulch and compost at highway construction sites can reduce rain runoff and lessen erosion, according to research from the LSU AgCenter.

A three-year study, funded by the state Department of Environmental Quality, found that using the mulch/compost mixture significantly reduced sediments in surface water, said LSU AgCenter soil scientist David Weindorf.

“Combating soil erosion on highway rights-of-way requires novel, multidisciplinary approaches that evaluate the issue from vegetative, soil and engineering standpoints,” Weindorf said in a news release.

Rad construction often requires removing trees from the right-of-way, Weindorf said. The harvestable wood is gathered, and the rest usually is piled and burned.

But the waste wood could be ground into mulch and used on highway embankments.

The research showed that a 3-inch layer of mulch and compost is best, Greg Waldron, project manager at DEQ.