A very important chapter as far as the forest in the novel is concerned is Chapter Sixteen, and it relates the symbolism of the forest specifically to the characters and their own situations. Consider the following description of the forest:
It straggled onward into the mystery of the primeval forest. This hemmed it in so narrowly, and stood so black and dense on either side, and imposed such imperfect glimpses of the sky above, that, to Hester’s mind, it imaged not amiss the moral wilderness in which she had so long been wandering.
Note the way that the setting parallels so specifically the actual situation of Hester in the shame and rejection she has faced as a result of her adultery. The woods seem to symbolise a place of mystery and are rather paradoxical. They at once represent freedom and inhibition, but at the same time confinement an entrapment.
This impression of the forest is deepened through the following presentation of the woods:
All these giant trees and boulders of granite seemed intent on making a mystery of the course of this small brook; fearing, perhaps, that, with its never-ceasing loquacity, it should whisper tales out of the heart of the heart of the old forest whence it flowed, or mirror its revelations on the smooth surface of the pool.
Note the use of personification to establish the forest as a magical place, and as a place that has its own secrets. We are left wondering what secrets the forest has and why it is that the forest should be so interested in Arthur and Hester.
Again and again such quotes present the forest as being in contrast with the town, which is devoid of mystery and where people live their lives according to a set of rules and laws created by men. There are rules and laws in the forest, but they are of nature, and very different and much more mysterious.