It’s the universal changing of time. If nothing else is certain in life, the leaf changes are.
Believe it or not, many of those vibrant colors are always there! They’re just covered up by the green pigment called chlorophyll. That green comes from the food-making process in the leaf and it’s what keeps it alive.
When the days start getting shorter, it sends a signal to the leaf to stop making chlorophyll.
As that green breaks down, it then reveals the other colors underneath. Each color comes from its own type of pigment. The brilliance of the color comes from the type of weather we had recently and the soil moisture.
Those vibrant leaves fall off in a very particular way. When the days get shorter, the vessels that carry water to the leaf are closed off, and a layer of cells start to grow at the stem of the leaf. These cells serve to slowly cut the leaf from the plant without leaving an open wound. As the leaves fall, the plant goes dormant, saving its energy to grow leaves again in the spring.
But once those leaves fall, don’t blow them into the street. Once they’re wet, they can be as slick as ice. It takes a car over three times the stopping distance on a road with wet leaves than if the road were clear and dry.
And speaking of moving those leaves. Have you ever felt exhausted after raking? It’s not just the act of raking, it’s the weight of the leaves. The average number of leaves on a mature oak tree is 200,000. It takes 360 dry leaves to make one pound. One tree has on average 550 pounds of leaves. If you add rain, wet leaves will weigh four times that.
So the next time you say you racked a ton of leaves, you’re not exaggerating! Because that’s exactly what the leaves from one tree can weigh after rain, just over a ton.