They are a good start on conifers. Would probably work at a much smaller scale. You're so close with that, I'd love to know how you got the noise so jagged. They would make delicious craggy mountains.

Instead of Clouds, I've been experimenting with Add Noise for forests. Start with a fairly small image. Add 3-15%(!) noise. Blur a little. Resize the image larger. Add more noise. A little more blur. Big up. Repeat to taste...

In greyscale, that can make a decent forest bumpmap. With gradient mapping it can also generate a good colormap.