Busy scenes can make for tough photography conditions...
One of the biggest mistakes you can make is looking to your wide-angle lens in a busy scene. In busy scenes, the more you include, the more visual clutter there is, making your image less appealing to the eye.
Typically, forests are very busy with trees, leaves, flowers, and even sunlight. In these situations, I turn to my telephoto lens and zoom in to my subject, eliminating visual clutter. I find that the best images are those with strong subjects where I can remove as much as possible from the scene.
Try it out next time you're shooting in the forest!