In "A White Heron" the story opens in the woods among shadows. Why did the author make that choice in the story? Explain how the shadows operate...

The first line contains a paradox of symbolism. There are shadows and a sunset that still "glimmered faintly." So, there is the foreboding image of the shadows juxtaposed with the hopeful image of the glimmering sun. The first paragraph ends with Sylvia taking her cow deeper into the dark woods: another foreboding image. Together, they follow the "shady-wood road." These images of shade do not suggest that the forest itself is evil, but they do suggest something dark to come. 

But that initial paradox sets up a few more. Sylvia is intimidated by the Hunter at first, but they do become friends. She did not understand how he could kill the birds he spoke so fondly of. But he is charming and Sylvia is enamored. "She had never seen anybody so charming and delightful; the woman's heart, asleep in the child, was vaguely thrilled by a dream of love." She wants to help him but does not want to let the heron be killed: She is conflicted. 

Another paradox appears regarding the symbolism of the shadows: 

She was not often in the woods so late as this, and it made her feel as if she were a part of the gray shadows and the moving leaves. She was just thinking how long it seemed since she first came to the farm a year ago, and wondering if everything went on in the noisy town just the same as when she was there, the thought of the great red-faced boy who used to chase and frighten her made her hurry along the path to escape from the shadow of the trees. 

She feels at home in the shadows and is also afraid of them. It just depends upon the circumstances and her state of mind. Here, the shadows symbolize both comfort and fear. This contributes to the theme of Sylvia's conflicted feelings for the hunter. At the end of the story, she continues to feel conflicted: 

Were the birds better friends than their hunter might have been, -- who can tell? 

The paradoxical symbolism of shadows mirrors her conflicted feelings for the hunter. Inevitably, she chooses to save the heron, thus showing her affinity for the woods and the forest creatures. (Her name, "Sylvia" resembles "sylvan" which means having an association with woods and/or the forest.) Note, in that paragraph illustrating the paradox of the shadows, that she is comforted by the shadows when she is alone in the forest but is scared when she feels chased by another person.