The description of McLendon's house is brought up in most discussions of this story. So here it is:
It was trim and fresh as a birdcage and almost as small, with its clean, green and white paint. (5.1)
This line gives us license to think of McLendon and his wife as caged birds. Their house might look neat and clean on the outside, but inside violence and fear stalk the rooms. If McLendon's home is a microcosmic representation of Jefferson, we can extend the symbolic power of the birdcage analogy to the whole town. Even though there are definitely hierarchies of power, with people like Will Mayes at the bottom of the hierarchy, everyone in Jefferson is caged within the heat and dust, of prejudice and hypocritical modes of behavior.