MemberJune 3, 2023 at 8:47 pm::
Autumnal leaves in vibrant hues are a beautiful part of the season, but those leaves are also a vital part of keeping trees alive.
Trees that have leaves that change color in fall are deciduous. (Evergreen trees with needles, which stay green to continue the photosynthesis process through the winter, are coniferous.) Deciduous trees usually have large, broad leaves.
Most of the year, these leaves are green because of the chlorophyll they use to absorb energy from sunlight during photosynthesis. The leaves convert the energy into sugars to feed the tree.
As the season changes, temperatures drop and days get shorter. Trees get less direct sunlight, and the chlorophyll in the leaves breaks down.
The lack of chlorophyll reveals yellow and orange pigments that were already in the leaves but masked during the warmer months. Darker red leaves are the result of a chemical change: Sugars that can get trapped in the leaves produce new pigments (called anthocyanins) that weren’t part of the leaf in the growing season. Some trees, like oaks and dogwoods, are likely to produce red leaves.
- This reply was modified 3 months, 3 weeks ago by Darshita.