PENNSYLVANIA, USA — The most colorful time of the year is just a few weeks away, as more and more leaves change from green to yellow, red, orange, and more.
Last year, I spoke to Dr. Christopher Hardy, a biology professor and curator of the Millersville University Herbarium, to talk about why leaves change color. I caught up with him again this week to discuss how this year's weather might affect our October colors. You'll read quotes from both discussions below.
The reason the trees go through this process is pretty simple.
"Over the years, plants have adapted themselves to sense when the days are getting shorter and the nights are getting longer, because what's going to follow that are the snow and ices," Dr. Hardy said. "They want to lose their leaves before that comes."
It's truly an act of self-preservation through evolution.
"If they get caught with an early snow or ice, those leaves provide a lot of surface area," Dr. Hardy said. "All that snow and ice is gonna weigh down the branches considerably."
The reduction of the amount of daylight is the primary catalyst for why trees lose their leaves. But, it can also be affected by other factors, especially temperature and drought.
"Dryness is something that stresses plants," he said. "Leaves are a big liability when it comes to water loss."
But, what affects the specific colors that we see?
Turns out, as long as we don't have a drastic drought in the summer with close-to-usual temperatures, most of the year only plays a minor factor. However, late August and September prove crucial.
"If we have some cooler temperatures and drier weather as we approach the fall, then that will accelerate leaf drop," Dr. Hardy said.
Late August and early September had immense amounts of rainfall hit the area in a short amount of time. Turns out, though, more-than-average rainfall doesn't affect our trees as much as not enough.
"Leaves are expensive when it comes to water," Dr. Hardy said. "They lose a lot of water through their surface area. In this case, we had plenty of rain. I would expect the plants to be happy to maintain their colors in that sense."
The FOX43 Weather Team would love to see every and all fall foliage pictures you can take throughout the month. Send them to us with the new "Near Me" feature on the FOX43 app. Your photos will not only stay on the app and be able to be identified to your township, street, even your neighborhood, but we may even use them on-air and online as well.
Until next time,
-Chief Meteorologist Bradon Long