American Society for Horticulture Science Dec. 29, 2010, press release:
Twenty-two grass species were included in a study conducted in the greenhouse at the Skogley Turf Research Center of the University of Rhode Island and in additional roadside trials on the shoulder of a nearby state highway.
Roadside embankments are generally constructed of subsoil and gravel, over which 2 to 6 inches of topsoil is spread. The subsoils are very stony with coarse-textured loamy sand between the rocks; topsoil ranges from medium textured silt to sand.
Combined results of the greenhouse and roadside trials showed Little Bluestem, Purple Lovegrass, and tall fescue to be the best choices for anchoring roadside slopes.
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