Here's why:
* Metaphor: A figure of speech that compares two unlike things directly, without using words like "like" or "as."
* In the sentence: "Pine needles" are being compared to a "gentle brown carpet." These are two very different things, but the sentence implies that the pine needles are similar to a carpet in terms of their color, texture, and covering the ground.
Let me know if you'd like to explore other literary terms!