Ok.. Here is one more video update. This shows the real power of masks, so pay careful attention. Watch it several times if you want. Of course.... In this case, I just picked some textures semi randomly, so they are not what I would use in a final image.

What this means is that once you have have your layers set up, you can make pretty much any changes needed, color, etc and only the part the mask says to show will be visible in the image. Compare this to directly painting your image using the Clone tool and "painting" the pattern onto the image. This could take quite a lot of time, depending on how much of the image you need to cover with the texture, then changing the opacity, and painting a bit more, wash-rinse-repeat. Quite a bit more work eh???

Next time, I will be going back to the original image for the final touch ups which will include adding a 50% gray layer set to overlay and using the burn tool to add some shadows to the creek and a bit to the underside of the "trees" to give them a bit more depth.