I love the changing seasons of Wisconsin. The fall leaves have always made me happy. I know that the season means Thanksgiving is coming. Turkey dinner. Pumpkin bars. Beautiful fall colors.
The season brings fun things like hockey, shopping, baking and time with family.
I did a little research on why leaves change color. Tim had told me about it, and I looked online.
Three pigments are involved: chlorophyll (green), Carotenoids (yellow, orange and brown), and Anthocyanins (red). The chlorophyll and carotenoids are there during the growing season. Anthocyanons are made in fall. They respond to bright light and excess sugars in the leaf cells.
Chlorophyll is produced all summer long, but slows down and eventually stops as the night length increases kn the fall. Then we see the carotenoids and anthocyanins show through!
Temperature and moisture during the summer months are the main influence. Warm and sunny days followed by nights that are cool but not freezing produce the best colors! Sugars are produced in the leaves on days like this. At night there is a gradual closing of the veins in the leaves. This causes the sugars to not be able to move out. Plenty of sugars and bright light make bright anthocyanins!
The moisture in the soil also affects the colors. A late spring or drought will delay fall colors by a few weeks, while a warm wet spring, good summer weather, and warm and sunny fall days with cool nights bring out the best fall colors.
The first picture was taken from the office I work in. The tree is at Holy Apostles church across the street. The other three are along the Root River Parkway in Milwaukee County.
Happy fall y’all! 🙂