Why Leaves Change Color in the Fall

September 30, 2019

On the first day of fall, it’s only appropriate that we write about spectacular autumn foliage. More specifically, we thought it would be good to discuss why leaves change color this time of year. Keep reading to learn more from the experts at Pro Tree Service in Chicago!

Let’s revisit your middle school science class for a moment. According to ScienceDaily, chlorophyll is a green pigment found in plants, algae, and cyanobacteria. You might remember that chlorophyll plays an essential role in the process of photosynthesis, which allows plants to absorb energy from light. 

So how does chlorophyll factor into the changing of leaves? Well, as summer comes to a close and temperatures start to become more fall-like, the chlorophyll in the leaves begins to break down. This is when we see the various color pigments, including red, orange, and yellow. Interestingly, the colors are most vibrant when the end of summer is dry, and the beginning of autumn consists of bright sunny days and cool nights.

Here’s an explanation of the four main leaf colors you’ll see this fall.

Green – Chlorophyll  

As aforementioned, this pigment is responsible for helping trees turn sunlight into food. Outside of the fall months, chlorophyll is the dominant color seen in most leaves until it fades away. We should also mention that trees turn to stored sugars to survive the winter once they stop producing food.

Red – Anthocyanin

Nothing says autumn like the beautiful red leaves found on Red Maples, Red Sumacs, and Scarlet Oaks. While other leaf colors exist in the leaf itself, anthocyanins are produced as the chlorophyll breaks down. The Swamp Chestnut Oak is another common anthocyanin worth checking out this fall.

Orange – Carotene 

You might know carotene as the chemical responsible for giving carrots their orange coloring. Yet many Chicago residents don’t realize that carotene also plays a major role in the changing of leaf color. Those who have a Super Maple in their yard are able to see carotene in action every autumn.

Yellow – Xanthophyll

Fall wouldn’t be the same without bursts of xanthophyll in beeches, ashes, aspens, birches, and oaks. Xanthophyll isn’t just limited to trees, though, as the chemical also contributes its yellow color to autumn corn and squash. 


Fall is a time to watch football, consume pumpkin-spiced everything, and, of course, enjoy the colorful foliage. But just because summer is officially over doesn’t mean you can stop paying attention to your trees for the foreseeable future. As we detailed in our fall tree care checklist, autumn provides the perfect opportunity to fertilize, hydrate, and plant.

At Pro Tree Service, we understand that trees require year-round maintenance. Whereas other local tree care companies only operate during the summer, we provide dependable tree care whenever you need it. 

Let’s take a closer look at how Pro Tree Service can be of assistance this fall.

Tree Removal

Many Chicago homeowners will attempt to remove their trees over the next few months. Unfortunately, a number of these people will incur injuries or damage their properties as a result. Here at Pro Tree Service, we suggest leaving this incredibly physical task in the hands of an experienced, well-equipped team.

Pro Tree Service has been Chicago’s choice for tree removal since 1989. Whether your tree is showing signs of aging or was recently damaged in a storm, you can count on Pro Tree for efficient, stress-free removal. Our full-service tree removal includes the removal of all logs, branches, and major debris.

Tree Trimming/Pruning

Let’s be clear: there’s no need for homeowners to trim and prune their trees on a regular basis. As we’ve discussed at length in previous posts, the constant removal of limbs and branches can shorten the life of some trees. This is where it’s best to defer to the skilled team at Pro Tree Service. The combination of our experience and having the right tools for the job allows us to keep your tree healthy and aesthetically pleasing. Learn more about our tree trimming expertise today! 

Don’t make the mistake of hiring just anyone to take on your tree care this fall! Contact Pro Tree Service today to request an estimate.

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