By glow of the tail-light I stumbled back of the car and stood by the heap, a doe, a recent killing. (5-6)
A car, most likely, killed the doe. Now, the scene is illuminated by the unnatural "tail-light" from the speaker's car. We start to see the car as representative of man and the damage he inflicts on the natural world—how he casts an ominous red glow over the natural landscape.
The car aimed ahead its lowered parking lights; under the hood purred the steady engine. I stood in the glare of the warm exhaust turning red. (13-15)
The car aims its own lights ahead, like heavy lidded eyes, the engine purrs "under the hood," steady like a beating heart in a human chest, the "warm exhaust" like breath in the cold, night air. Suddenly, the car seems different. The personification makes the car seem part of the natural world—a living, breathing thing.
around our group I could hear the wilderness listen. (16)
From this description, we really get the sense that the group (speaker, doe, fawn, personified car) is surrounded by nature. In fact, if we think about the scene, the group is literally surrounded: trees, animals, mountains, rivers are all around. Not only is nature everywhere, it is listening. Stafford's word choice, "I could hear the wilderness listen [our emphasis]," adds a sense of judgment—it's like the speaker can feel nature waiting to see if he will do the right thing or not.