This is a re-do. I tried to write a post from my iPad and failed, so am trying again on the PC.
Once again I missed my opportunity to photograph the exceptional fall color on display on the North Shore of Lake Superior, but fortunately, a nature photographer friend who lives up there has posted his photos this week. And are they ever dramatic! Please go to Paul Sundberg’s website to see his amazing photos of fall color in northern Minnesota.
Meanwhile, in southern Minnesota, the trees have suddenly (as in, over the week-end) popped into blazing color. It makes you just want to stay outdoors all day. I love Indian Summer.
Warm days and cool nights force the trees to break down their chlorophyll, unmasking all the xanthophyll and carotene photo pigments in the leaves, which produce the yellow, orange, and red colors. I wrote more about the chemistry of the color change last fall — (“you know it’s fall when…”).
Back Yard Biology 