Monday, October 15, 2012

The Mystery of Autumn... The Facts May Just Surprise You

 There's a mystery to be solved...
 and Scientists are still working to figure it out.

Why do the green leaves of Summer  
transform into blazing hues of  
Red, Yellows and Orange 
in Autumn?

You may think you know the answer.
And actually, you may know some of the facts.

But there are other facts that may just surprise you.

You may already know...

Plants use chlorophyll and sunlight to make their food.
The chlorophyll is what makes the leaves green.
 As plants stop making food in the Fall 
the green chlorophyll disappears. 

As the chlorophyll fades away,
the red and orange and gold of Autumn appears.

The vibrant colors were always there, 
but were hidden by the green of the chlorophyll. 

The cooler temperatures 
and shorter days of Autumn
signal the leaves to begin the change.

But did you know... 

Yellow leaves undergo one sort of color changing process 
and Red leaves another?

Scientists have discovered 
something very different goes on in red leaves. 

As their chlorophyll drops,  
they would also turn yellow if not for the sudden rapid production
of a brand new red pigment called anthocyanin.

Anthocyanin was not previously present in the leaves.

This surprising new revelation has scientists wondering...
"Why would a leaf with only a week or so longer to live 
bother producing an entirely new pigment?"

Anthocyanin may serve as a protective pigment 
that helps trees in nutrient-poor or stressed places 
maximize the nutrients they can draw from the leaves 
before they are dropped to the ground.

So, where every drop of nutrient counts the most...
like perhaps on some nutrient-poor hillsides of North Carolina...
red is the color of autumn.

Another theory for explaining red leaves 
is that they are the result of 35 million years 
of trees battling insects looking for places to get a last meal 
and lay their eggs in the fall. 

Red leaves are harder for some insects to see, 
 so they tend to go for the yellow leaves.

Want to know more?

Here's a great website 
where I gathered much of the information I've shared...
it is fascinating.


  1. I had read this explanation for the shifting leaf colors somewhere in the past, and was trying to remember the story behind the mystery just recently. Thanks for the reminder. It is really quite fascinating that plants and trees have so cleverly adapted to the changing of the seasons.

  2. This is so interesting! Anthocyanin pigments are such hot news. I love all these unanswered questions! 

  3. Isn't it fun to learn something new?

  4. Fascinating, thank you for the interesting information.  I think I look from now on in a different way to the colouring leaves.
    Regards, Janneeke 

  5. Very interesting Carolyn, but I still like the "painted by fairies" theory the best!

  6. Oh I've not heard that theory before... lovely! Yes I agree.

  7. Here the scrub oak turns orange... the first Autumn color on the mountain above us.

  8. I agree, Donna. I actually came away with questions as well... so much more to be learned. The link was fabulous... especially interesting about the east west versus the north south mountains.

  9. It is so very fascinating, Carolyn. And it fascinates me even more when bizarre color combinations and variegated colors appear on the same tree, plant, or bush. I just drove across a good portion of my state today and the Oaks were incredibly lovely. I wish I could have stopped right off the interstate several times--it was stunning!

  10. Donna@Gardens Eye ViewJanuary 9, 2013 at 7:50 PM

    What's even more fascinating is there are only certain trees that produce this red pigment and others that do not at all...and then what about the orange color that comes from the red many questions... fascinating Carolyn

  11. So glad you enjoyed it, Cat. I never imagined that in Texas the trees don't change color in the Fall.

  12. Hermoso tu blog y muy interesante la información sobre el cambio de color de las hojas en otoño!! Un abrazo grande desde Argentina.

  13. Thank you for visiting! Hugs right back to you!    

    Translation: "Beautiful your blog and very interesting information about changing color of leaves in autumn! A big hug from Argentina."

  14. So interesting, Carolyn.  Thanks for sharing.  I love the thought of the colors being masked by the chlorophyll...I can imagine I have fall going on with the rest of the country!  The colors are in there...just masked!


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