By Jack MacRae The burgundy leaves of sumac fill the Fox Valley’s fall woods.  The hue comes from the pigment anthocyanin and is greatly influenced by the weather.  Here is how: Cool nights (below 45f) inhibit the tree’s chlorophyll production.  Without chlorophyll, sugars accumulate in the leaves.  Increased sugar leads to a rise in anthocyanin in the leaf.  The more … Read more