Fall Colors Starting to Show
We are starting to see splashes of color across southeastern Wisconsin. Some folks are worried that the colors will come too quickly, but the reality is October is the month for the vibrant colors to peak across Wisconsin.
While we experienced abnormally dry conditions this summer, the trees seem to be in pretty good shape and not too distressed. The rest of the state has enjoyed plenty of rainfall this year, so that shouldn't be an issue. The picture above is the expected peak of the color in October.
Please keep sending your fall pictures to [email protected] You can also upload your photos and videos to the Ready Weather App. In order to understand why we see the color change this time of the year, I pulled some information from the United States National Arboretum website.
"The process that starts the cascade of events that result in fall color is actually a growth process. In late summer or early autumn, the days begin to get shorter, and nights are longer. Like most plants, deciduous trees and shrubs are rather sensitive to length of the dark period each day. When nights reach a threshold value and are long enough, the cells near the juncture of the leaf and the stem divide rapidly, but they do not expand. This abscission layer is a corky layer of cells that slowly begins to block transport of materials such as carbohydrates from the leaf to the branch. It also blocks the flow of minerals from the roots into the leaves. Because the starting time of the whole process is dependent on night length, fall colors appear at about the same time each year in a given location, whether temperatures are cooler or warmer than normal.
During the growing season, chlorophyll is replaced constantly in the leaves. Chlorophyll breaks down with exposure to light in the same way that colored paper fades in sunlight. The leaves must manufacture new chlorophyll to replace chlorophyll that is lost in this way. In autumn, when the connection between the leaf and the rest of the plant begins to be blocked off, the production of chlorophyll slows and then stops. In a relatively short time period, the chlorophyll disappears completely."