NORFOLK, Va. — October is the first full month of fall, which means: cooler air and... pumpkin spice everywhere. Well, that, and the leaves are now changing.

Those changing colors decorate the skylines and the sidewalks but there's chemistry and not just weather behind it!

When it comes to the green in the leaves that we see most of the year, that's due to chlorophyll. That's the prominent chemical through much of the year and it causes the green to cover the other colors until chlorophyll production decreases.

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Carotene causes the orange pigments in the leaves and if that sounds familiar beta carotene is responsible for the carrot's orange color.

We hold xanthophyll accountable for the yellows that shine through in some leaves. It's also the culprit responsible for the colors in egg yolks and fall squashes, like spaghetti squash!

The red tint, however, doesn't develop until the seasons change while the other colors are simply overshadowed most of the year by the green hues.

You can check out this map, which shows predictions for peak fall foliage across the country.

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