Happy Fall, Ya’ll: Autumnal Equinox

MADISON, Wis. (CIVIC MEDIA) – The fall brings about changes in temperature, leaves and sunlight as Mother Nature paints the landscape pretty this season, with some spots already changing colors.

On Monday, Sept. 22, the seasons officially shift. It’s called the Autumnal Equinox. The event occurs when the Earth is perfectly tilted to give us equal hours of daylight and darkness. I’m sure you’ve noticed it’s darker for longer in the morning now and the sun is setting earlier, too. Shorter days happen fast. In just the month of September, we lose almost an hour and a half of daylight. That’s also why the leaves are starting to change colors now.

Trees are sensitive to changes in their environment. The sunlight triggers the tree to produce chlorophyll, which is how it makes energy and why the leaves are green. It’s a process called photosynthesis. So, in summer, we simply have more hours of sun available. Now, that’s being pulled away. Just like how our moods can decline with less light, so too does the foliage. 

With vibrant reds, oranges and yellows that pop, it’s no wonder people color-chase in our Northwoods. Travel Wisconsin has an updated map of places and percentages the leaves are changing. It also forecasts a peak date, so you can set up your travel and road-trips plans ahead of time.

Red leaves are usually on maples or oaks. They have anthocyanins that turns them to that color. It’s also found in blueberries and cranberries, giving them that color. Carotenoids flare the orange, like a carrot, and Xanthophylls produces the yellow leaves on Aspen and Poplar trees. It’s also found in things like corn and papayas. 

As the veins from the leaf start to close off for winter, the juice retreats into the branch and shuts the door, covering our forests and landscapes. The DNR says that it’s actually beneficial – it keeps the soil filled with nutrients as they decompose. 

Wisconsin high winds and heavy rain can easily knock the leaves off the trees, as we all know. The weather type plays a huge part of the color change and timeframe. The National Weather Service says a drought or an early frost could make the leaves fall off of the trees before they’ve even had time to change colors.

Currently, the state is not in a drought, and above average high temperatures have snuck in recently. The most stunning leaf displays follow a period of warm days filled with sunshine and cool nights for the veins to narrow and trap the sugars.

For meteorologists, the Autumn season actually started on Labor Day, Sept. 1. They abide by a different schedule because it’s easier to keep track of records and changes on a three-month basis rather than on an Earth axis that wobbles. Peak is expected the second week of October up north, with central Wisconsin to follow and southern parts of the state closing out the month splashed in nature’s beauty.