Okay, so I took the various bits of advice: I designed a textured tree brush from aerial photos of swamp trees, I added a tiny splash of color, especially to the water to make it read better, and I fleshed out the details a bit more. It's not perfect yet, but I think I'll call this one done and move on to the next project.
Thank you all for your advice. I really appreciate it
I apologize for the size being on the small side. Photobucket seems to be shrinking my work down to an acceptable size.