Articles

J

Kortright Centre's Forestry Pamphlets, authored by a forest scientist. These will be published when permission is secured.

Fall Colouration: Nature's Paintbrush, Part One: The Basics

Colours in the leaves are caused by presence of the following chemicals
   

GreenChlorophyl

Produces sugars from water, air (CO2) and sunlight.
Breaks down in fall and reveals other colours.

YellowXanthophyl

Hidden by chlorophyl - revealed in fall

OrangeCarotine

Hidden by chlorophyl - revealed in fall

RedAnthocyanineProduced during late summer and fall
BrownTanninAlways in leaf - notable in oak etc. Can inhibit leaf fall

The Article: PDF format. If problems, contact me. (Dialup will take a while to download . The MSword file is much larger)

Fall Colouration: Nature's Paintbrush, Part Two: The Inside Story

This pamphlet wil be an in-depth look at what happens in the tree from spring to winter, causing leaf colouration and eventual leaf fall. Reference to the location of various Canadian communities, related to sun angle and day length will also be covered.