Planting and Managing Switchgrass for Forage, Wildlife, and Conservation
The upright growth provides wildlife some overhead cover for protection, quality nest sites, and free movement which facilitates food searching. In established stands, there is little disease problem and no insect pests. Since it is a perennial, properly managed switchgrass should never need to be replanted.
The link address is: http://www.ext.vt.edu/pubs/forage/418-013/418-013.html