Marc Abrams, professor of forest ecology and physiology at Penn State, has some great news. With the predicted mild drought and relatively low temperatures, trees in the Commonwealth of Pennsylvania are set to look spectacular as their colors change in the next few weeks. Professor Abrams has studied the changing of the seasons and how it impacts the color and intensity of the changing of the leaves for the past twenty years. He has this to say about the colors this year:
This is an unusual year because there doesn’t seem to be anything to worry about that could negatively affect the foliage. Every other year there was always something that could dampen the colors in the display, but this year there is nothing on my radar. There are no widespread, great stressors of trees, and we have had adequate moisture across the state through the growing season.
I don’t know about you, but my favorite time of the year is when the leaves turn. The air is filled with that aromatic, sweet smell of leaves before the skies over Happy Valley become gray and windy. In fact, the only time I wish I had a car up at school is during this time of year where I could be out on the roads around State College enjoying the scenery.
For those of you with scientific inclinations, here is Penn State Live’s explanation about why the colors in the leaves change:
Cooler temperatures signal deciduous trees to stop producing chlorophyll, the green pigment responsible for photosynthesis, Abrams explained. Photosynthesis is the way plants trap light energy and convert it to sugars and starches, the food and building materials for plants. As the chlorophyll breaks down and disappears, it unmasks other leaf pigments. It’s these other pigments — called xanthophylls and carotenes — that create the glowing yellows and oranges seen in the leaves of yellow poplar, hickory, sycamore, honey locust, birch, beech and certain maples. After chlorophyll production stops, trees also produce another pigment in their leaves called anthocyanin. The anthocyanins create the brilliant reds seen in red maple, sassafras, sumac and black gum.