Well, I was supposed to do this in conjunction with last weeks assignment. However I wasn't reading ahead, so I will just do it this week.
Look at a tree and it's shape. Look at the part the leaves play in making the shape you see and look at the part the trunk and branches play in making the structure you see. Look for patterns made where the foliage is dense or light. Look for dark and light and other color changes that come about on the leaves.
Look at a tree for one hour in the week. Write every specific thing you see about that tree. Make a list of other things that you think are related in structure to a tree.
If anyone is following these with me, send me your drawing and I will post it. See you next week.