The physiology of deciduous trees (start time: 11:09 ) For many people living in places with four distinct seasons, such as here in Colorado, a favorite pastime at this midpoint in autumn is watching the faded leaves fall from their branches, and listening to the crackling sound while raking up the dried leaves. In this week’s How On Earth show, we explore questions like, Why do the leaves of aspen, ash and other deciduous trees “change” color in the fall?  (Spoiler alert: They actually reveal their true colors.) Why do they shed their leaves every fall? And what happens to the naked trees in the winter? Host Susan Moran interviews Dr. Stephanie Mayer, a senior instructor emerita in the Department of Ecology and Evolutionary Biology at the University of Colorado Boulder.

-Resources for winter watering:

Colorado State University Extension

Denver Botanic Garden

-Resources for citizen science opportunities:

The National Phenology Network

Host/ Show Producer: Susan Moran

Cohost/Engineer: Joel Parker

Executive Producer: Beth Bennett

Headline Contributors: Lorraine Healy, Max Hebebrand, Shelley Schlender

Listen to the show here: