by Peter Lowe, Native Landscape Manager
On these crisp October mornings when I leave for work I begin my trek in darkness with the soft glow of moonlight descending behind me. As I reach the practically empty stretch of state route 161 I am greeted by the rising sun and the revelation of color change taking place in the treetops this time of year. On this particularly dreary Wednesday morning, I was listening to NPR when the host interviewed an expert in climate change and how it can negatively affect fall color change and in return the tourism in areas that depend on seasonal change. The expert went on to say how we won’t lose our fall colors but the colors themselves will possibly be dimmer or not as diverse or more monochromatic in terms of values of yellow or red. This brief news blurb had me day dreaming about all things fall – from candy corn and Halloween costumes to pumpkin spiced coffee on a foggy morning. As always, my mind often drifts to deciphering how things work – and the reason behind fall color was not spared.
The greatest displays of fall color can be seen when we have warm, sunny days combined with cool, crisp nights. Were we to experience below freezing temperatures, our color display would dull and end abruptly. The change created in our foliage is influenced by so many factors that no two falls are alike. From spring rains to cloudy Septembers it all determines the WOW factor.
The one constant in every autumn is the length of days. The fall process begins June 21 with the summer solstice, the longest day of the year. The shorter days and longer nights are a signal to stems to being shutting down transportation of nutrients to and from the leaves and ultimately blocking those routes with a corky layer of cells. This triggers the decreased production of chlorophyll, the green color in leaves. Unknown to many, chlorophyll hides carotenoids or the yellow pigment that is always present in leaves. As the leaves begin to shut down sugars get trapped within the leaves and begin to breakdown giving way to anthocyanins, the red pigments in leaves. These pigments are not present year-round and only show up in a select number of species. There are many theories behind the seasonal color change, but scientists have yet to discover its true reason. Me, I would like to think that it is nature’s way of paying it forward. Fall is so much more than just a biological occurrence. It is a time of year that inspires us more than many of us would like to admit.
Autumn often gets a bad reputation because it brings in winter. Winter is perceived to be a cold, dead season. That is why fall is such an encouraging and motivating time of year, life is never more appreciated or held in higher regard then in the face of death. As the leaves change color and wither away poets, artist, authors, families, young love, and those with a song in their hearts are inspired to take the bull by the horns.
So I challenge you reader, push distraction aside and step outside to take in the dazzling displays of carotenoids and anthocyanins… while they last.