This tutorial has a variety of ways to create pieces of a landscape such as trees, waterfalls, mountains and rocks. It is meant to be used as a supplement for students to create their own landscape using the flat shape style in Adobe Illustrator. I use the artwork from an artist named Hemanta Sing. I have been unable to find his original posts, but you can follow my Pinterest Board to see what I show my students https://www.pinterest.com/krosskreations/illustrator-landscapes/
Students can use this to figure out some basics and then enhance them to make it fit their ideas.