Outdoor Radio: The Phenology Of Fall

Oct 21, 2015

We all learned the basics of how and why leaves change color in the fall. But on this edition of Outdoor Radio, we take a deeper look at the chemistry of foliage.

Biologists Sara Zahendra and Kent McFarland are tromping through the snow to study the leaves with Joshua Halman, a Forest Health Specialist with the Vermont Department Of Forest, Parks and Recreation. Halman explains the phenology behind the yellows, oranges and reds that we see as the trees transition into winter.

The department has been monitoring Vermont's trees for 25 years, recording the color change and leaf drop in various places around the state. Halman says the work has documented the impact of climate change.

"Seen over this time, the peak color and the main time for leaf drop has actually become later,” Halman explains. “What we're seeing since we started recording our fall phenology data, that on the average, foliage is peaking about eight days later in that 25 year period."

You can find more information at the Vermont Deptartment of Forest, Parks and Recreation's Forest Health Monitoring page, and on the VCE blog, Turn Red or You're Dead

Check out the Vermont Center for EcoStudies for their complete "Field Guide to October," and their piece, "Abscission and Marcescence in the Woods."

Broadcast on October 22, 2015 and October 23, 2015

Outdoor Radio is a monthly feature produced in collaboration with the Vermont Center for EcoStudies in Norwich Vermont. The program is made possible by the VPR Journalism Fund.