Ten Things You Can Do to Celebrate Arbor Day December 22, 2015 By Betty Munis 10. Learn how Arbor Day began. 9. Find out about Idaho’s state tree, the Western White Pine.. 8. Buy a forest license plate and support forest education programs. 7.Learn how paper is made and try it with your friends or family. 6. Proudly wear an official Idaho Arbor Day T-Shirt. 5. Learn about all the neat things we get from trees. 4. Learn how to identify trees and impress your friends. 3. Send an Arbor Day e-card to your friends and family. 2. Share your tree planting experience on IFPC’s Facebook page 1. Plant a Tree.