It's likely referring to a cottonwood tree.
Here's why:
* White: Cottonwood trees produce fluffy white seeds that look like snow when they're released in the morning.
* Red: The bark of mature cottonwood trees is a reddish-brown color, which might be associated with the afternoon sun.
* Green: The leaves of cottonwood trees are a vibrant green, which is the standard color during the day.
* Black: The darkness of night could be interpreted as the absence of the tree's color.
Let me know if you'd like to try another riddle!
