I am having a lot of trouble trying to gain an understanding of painting forests. Dense forests and wooded type forests. It seems the second I start I am lost, I cant figure out where light should or shouldnt go, how to make plants still look like plants and how to still show depth amongst all the foliage.

Would anyone have any tips or tutorials that may help me gain a little more understanding of how to approach and draw these landscapes?

It would really be a great help Thanks!