Incorporating some wood such as roots, logs or stumps softens the rock and adds to the illusion. Place these next so they
can be blended in with smaller rock and gravel. Situate them in positions where water would naturaly wedge them in.
Last of all add the small rock or gravel that represents the water. Cover the bottoms of the larger rock and stumps to
make them look like they have been there for some time with grvel being deposited & building around them.