BnW is not for that pic.
The Greens offer contrast the picture needed. It may have worked well if there was a bit of snow in the pic then there would be great contrast but currently there are too many tones of grey.
However, if a person were stalking up the creek away from camera in the mid 1/3 of the pic BnW may work… Good use of leading lines mixed with framing to make the viewers eyes wander and wonder what is up the creek.