What's happening in nature this week?
Over the past week, we’ve been noticing the leaves changing color as our annual fall foliage display begins. But why do leaves change color this time of year?
As you may know, leaves use sunlight to produce energy (as sugar) for trees through a process called photosynthesis. The sunlight is absorbed by a chemical called chlorophyll in the leaves. Chlorophyll gives leaves their green color.
As the nights get longer and there is less sunlight for the leaves to absorb, the tree begins to sever its connection with its leaves. Chlorophyll remaining in the leaves continues to make sugar, but that sugar gets trapped in the leaves and forms anthocyanin, which produces red and purple colors.
Meanwhile, the chlorophyll in the leaves breaks down, so their green color begins to fade. Carotenoids, orange and yellow colors that are always present in the leaves, but hidden by the green chlorophyll, begin to show through. The different blends of chlorophyll, carotenoids, and anthocyanin give each leaf its unique fall coloration.
Although we might wish for the vivid colors to last, eventually all of these pigments break down, leaving behind only tannins, which give leaves their brownish color.
East Rock Park
Each week we will share a kid-friendly hike or other outdoor adventure.
This week, East Rock Park offers an easy stroll with wonderful views of the fall foliage and across New Haven!
About this series
In this time of virtual learning and social distancing, we seek to support teachers and families in getting outside in safe and healthy ways. We hope this series provides content and activities to help your students or your family engage in nature-based learning, whether you are learning in person or virtually.
Some of the funding we rely on to keep Nature Notes free comes from the Robert F. Schumann Foundation and The Claire C. Bennitt Watershed Fund, established by the South Central CT Regional Water Authority.
