I saw an interesting video How to create realistic looking trees.
To create the background and the environment I need to create trees. As I understand it, we can create in different ways. This video uses an interesting way to create realistic trees.
I created an intellect map that helped me understand what trees I need. It really helps me find references. By the way, pay attention to the great site with lots of photos!
Here's what I got:
Now that I know this approach, I can create any type of tree with the details I need.