It’s that time of year again, when our gardens are aflutter with leaves falling (and falling and falling), blanketing our beds with brilliant shades of yellow, orange and red.
Ever wonder why leaves fall?
Many don’t realize that it’s basically a tree’s way of protecting itself from a bunch of freeloaders! You see, once colder temperatures begin to arrive, a deciduous tree starts producing an abundance of bumpy ‘abscission’ cells whose purpose is to literally shove the leaf off of the branch. These cells continue to form along the thin line where the very end of the leaf’s stem attaches to the tree, slowly building up and pushing the leaf farther and farther from the branch. Once enough of the cells accumulate, the slightest breeze then carries the leaf to its final resting spot.
So why do deciduous trees do this in the first place?
Well, since a leaf’s primary purpose is to provide food for the tree, when the tree begins to go dormant it simply doesn’t need the leaf’s services any longer.
And the last thing the tree needs is to expend its precious conserved energy by continuing to support a half-dead ‘freeloader’!
***Now that you know why leaves fall, do you ever wonder why leave turn the colors they do? Check out my article over on Fiskar’s site to read why!
6 Comments
You’re lucky to have so much fall color! I can’t wait for our orchard to mature a little. The most brilliant color we have at the moment is the peach tree, but living in the middle of a mixed evergreen forest, our predominant fall color is…well…green! 😛
Yes, well according to Kermit green is a pretty good color, too! 🙂 You’re right, though. We always have so much more fall color than folks realize – from the Pistache, Gingko, Crepe Myrtle, Japanese Maples and Ornamental Pears it’s really quite beautiful up here in Northern California!
I have been spreading tons of leaves that end up in my carport onto a space that was created when we terraced one corner of the garden. I still don’t know what I am going to plant there, but there is a great lasagna garden going with layers of hay, loam builder and leaves. Some fave beans were seeded for nitrogen fixation and in the spring I will have some great top soil to use.
I wish more people would realized the power of dead leaves instead of throwing them away.
I need to go out with camera before it is too late.
Good for you, Laura! You’ll have the world’s best soil in that area once you decide what to plant. Lasagna gardening is the best, isn’t it? I can’t wait to hear what you decide to plant!
I used to teach this to my students each fall about the leaf drop and the changing of the colors. It was always a surprise to the parents who had never known this. I don’t think anyone had every told me this until I was an adult.
Eileen
Your students were very lucky that you took the time to teach them all about the science behind nature, Eileen. I never knew why leaves fell either until much later in life.