What symbol does the author use in the first line and what is the meaning of that line?

Updike's poem uses the first stanza as a type of exposition to help the reader gradually obtain the feel of the story being told.  The symbol of the road that runs "past the high school lot" allows the reader to understand that along said path, something great once existed.  We get the impression that the town is small, and rural, indicating that like many small towns, local legends loom large and that local sports dominate the town's psyche.  This symbol of the road past the high school helps to set the stage for Flick Webb's story and his narrative.  The symbol of Pearl Avenue running free and then being cut off quite suddenly is also of note, as it might help to illuminate Flick Webb's own dreams and his own stature. The third line continues this first line image with the notion of "before it has a chance," which could be another apt way to describe Flick Webb's hopes and dreams.  In this first line symbol, Updike links small town geography to small town mythology.