Phenology is the study of timing in nature, whether it's crocuses emerging in the spring, leaves falling from trees, or Canada geese heading south for the winter.
And it's tricky business for fall foliage...

Read more in the below and check out photos of Arizona at www.AcrossArizonaTours.com

Will climate change lead to later fall foliage?

By David Sharp, Associated Press

PORTLAND, Maine (AP) — Clocks may not be the only thing falling back: That signature autumn change in leaf colors may be drifting further down the calendar...

http://www.indystar.com/usatoday/article/50775258?odyssey=mod%7Cnewswell%7Ctext%7CLiving%7Cp