Climate Corner: Climate change affects leaf-peeping, too
Oct 9, 2021
I remember shuffling as a child through the rainbow of fallen leaves as I walked past City Park to my fifth-grade class at Park School. I would pick up the prettiest ones on my way home and my mother would help me identify them. She loves botany; the study of flowers and trees intrigues her. She became my resident specialist encouraging me to collect those radiant gems in the fall.
Today, as we consider fall leaf-peeping time, I find the leaves do not have the same vibrant colors of my childhood. Maybe it’s because I am looking through adult eyes, or maybe it is because climate change has been an enemy to our trees. So, you ask, how in the world does climate change have anything to do with the fall colors?
A paper released from the Department of Biology at Appalachian State University shared a list of ten environmental factors that can be the reason for the loss of our so much enjoyed fall colors.
1. Higher temperatures cause changes in the sugars during the photosynthesis process in all of our plants including our trees. This sugar is needed for color development.
2. Climate change is causing changes in the amount of precipitation and even the timing of rain, snow and sleet. As we consider the deciduous trees that provide the color we so enjoy, the changes in precipitation patterns will continue to cause harm to them. Many of us in this region have seen an increase in spring rain and an increase in August droughts; both can have deleterious effects on leaf color.
3. Humidity levels are changing because of temperature and precipitation.
4. Changes in the cloud cover can affect the amount of light striking plants, including trees. And as you know from your high school biology class, light is an important factor in the food production process in plants called photosynthesis.
5. Increases in the growing season which change the behavior of leaves as they grow in the spring and change in the fall. According to NASA the frost-free season or growing season may increase by eight weeks by the end of the century!
6. As agriculture practices, such as the use of fertilizer, pesticides and hog production, etc., continue, the release of nitrogen into ecosystems will continue to rise as well. These nitrogen emissions contribute to acidic deposits and acid rain.
7. Nutrients are leached out of soils by continued acidic deposits. Many of these acidic deposits are a result of the use of fossil fuels. According to the U.S. Forest Service, “In sensitive ecosystems, these acidic compounds can acidify soil, surface waters, affecting nutrient cycling and impacting the ecosystem services provided by forests.”
8. Some tree species are migrating north to escape heat. According to the U.S. Forest Service, data show that 70 percent of tree species are migrating. “This ‘range movement’ northward occurs when more seeds germinate and seedlings thrive at the northern edge or higher elevations of the species’ range than at the southern edge or lower elevations.” This migration is why so many of us go to the mountains to do our tree peeping.
9. We are losing some tree species in certain geographical locations because they cannot migrate nor can they survive the environmental changes.
10. And, finally, as species migrate, we will see changes in tree competition because some species migrate causing competition while invasive species and even more and newer pests will increase.
As I am researching and writing for this article, I find my nostalgia increasing. My sadness about the diminishing beauty of something I have treasured all my life may be because of the romantic nature of my memory or because of the environment. I believe it is a bit of both. The glimmer of hope is, that in the trees and forests we could find a partial answer to our problem by the use of reforestation. But, that’s another story for another time. In the meantime, I hope you can find those gold, red, and yellow nuggets in your neighborhood this fall. Enjoy!
Nenna Davis, B.S Zoology/Botany; MA, Organizational Communication