Chances are, your lawn covers a pretty large part of your property. However, in many landscapes there are some spots where, for one reason or another, grass will not grow. (Most often there is too much shade.) One of the easiest ways to manage a bare soil area around trees is to plant some sort of ground cover. In our area, English Ivy, Asiatic Jasmine, or Hosta, for example, will grow in the heavily shaded areas with little care.
In areas other than around trees, there is a newer variety of St. Augustinegrass that has shown to be drought and shade tolerant which is the Amerishade St. Augustinegrass.