An evocative nature poem. I can feel the river gurgling through rocks down the slope in the thick woods. "books in brooks and sermons in stones'" come to my mind when I read poetic reflections on the tranquil forest scene. Wind is free to blow with no blocks of concrete. Its howl is clear and loud. It rustles through trees leaving the leaves moving for long.
The river plunges forward to the rocky incline. Its final goodbye to the sojourner in the woods.

Imagery-
Images of nature are impressive. They appeal to eye, ear and the touch sense..
"The wind howls excitement for air."
wind and air are used for different contexts. So it is with the line "the river is calm and sound."

It flows well.

Write on!