Why Leaves Change Color in the Fall

Why Leaves Change Color in the Fall

Autumn is my favorite season – crisp, fresh, and full of promise. I want to wear plaid, sharpen pencils, and buy a new journal.

Each year I eagerly anticipate leisurely walks among the brilliantly colored foliage that dots my local landscape.

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Birches,Betula spp., and tulip poplars, Liriodendron tulipifera, are awash in yellow.

Maples, Acer spp., staghorn sumac, Rhus typhina, and Virginia creeper, Parthenocissus quinquefolia, turn a fiery scarlet. 

And the multihued orange, purple, red, and yellowoakleaf hydrangeas, Hydrangea quercifolia, are rivaled only by the equally diverse hues of sassafras.

Over the years there have been many truly dazzling displays, but sometimes the palette is more muted. I wondered if I really knew why, so I explored the life cycle of a leaf.

In this article, I’ll tell you what I learned about why leaves change in the fall. You may be surprised to discover that even scientists don’t fully comprehend the phenomenon.

Here are the topics we’ll cover together:

Let’s get started.

Woody perennial shrubs, trees, and vines that drop their leaves are described as deciduous, as opposed to evergreen.

Green foliage looks green because it contains a pigment called chlorophyll that doesn’t absorb green light.

During a plant’s life, it absorbs carbon dioxide and water and transforms them into food via photosynthesis.

Photosynthesis is a two-step process that takes place inside chloroplasts, microscopic organelles or structures within the cell walls of plants. The first phase is light-dependent. The second phase, or the Calvin cycle, is