Trees are Easy!

You know what I mean. Trees  are up and down with bushy leaves all around.

But rocks on the other hand are tricky. They are gray, brown, and many colors in between. Plus they have shadows and are not all round!
Many times we line them up like a herd of turtles, or outline them like a circle then color them in.

Use many colors to make your rock. You can let them pick up the darks first. Then add the high lights. Look close and you will see the rock has many sides and you must pick your light source. Then add the lights.

Now lets keep our brushes wet and the rocks gray.