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Why Leaves Change Colors
October 26, 2009
Here we are, the last week of October.
Time sure flies when you're having fun.
I know time speeds up as we get older, or so it seems.
As most of you know, we took a quick get away to northern Michigan last weekend to look at some fall colors and to enjoy some of God's creations.
The pictures in this letter were taken from our visit up north.
Above you will see Point Betsie Lighthouse and a view of Lake Michigan from that vantage point.
Also, are a couple of pictures of Sleeping Bear Dunes National Lakeshore.
And of course, my two favorite girls (Karen and Yolanda) on the dunes over look more than 450 feet above the Big Lake.
While standing there, you can actually see the curvature of earth along the lake.
The same goes for fall colors as well.
The weather was chilly and windy, but we did have some morning sunshine.
Sunshine is needed to show off the fall colors.
Colors were patchy, but there were several jaw dropping panoramic views from time to time.
Okay so I'm not a professional photographer, you'll cut me a break wont you?
All in all, it was an enjoyable time and we were impressed by the volume of people that were enjoying nature as well.
Back at home.................
We were blessed with a short Indian summer this past week.
Yes indeed, we managed to hit the 60's a couple of days and then back to reality.
Gloomy rainy days.................
I'm not a fan of gloom, but we can always use the rain.
The warmer dry days did allow me to get a few more chores taken care of.
Dark-eyed juncos have arrived in force.
I don't mean a couple, I mean several of them all at once.
I still have a visiting White-crowned sparrow hanging around for now.
It too shall head further south soon.
Flocks of robins continue to enjoy the fall feasts.
Even in the north country, you may see a few that brave the winter.
The local air-space would give the most experienced air-traffic controller nightmares.
Flocks of Canada geese are everywhere and flying in different directions as they practice formations and calling.
Maybe you have noticed how the local families are growing into larger flocks.
Now, toss in several ducks and a few Mute swans, several smaller birds and the sky is one wild place.
Sometimes the ducks and or geese fly so close to each other, you can see and hear when the wings collide.
As with the robins, many of these waterfowl never make the trip south.
As long as there is food and open water, many waterfowl will stay close to home.
A couple of things for your to do list.
If you haven't yet, check your birdbath heater and get it set up.
A cracked birdbath from ice expansion is not a good way to start your day.
Be sure to get your young trees wrapped too.
Sun scald can ruin a young or newly planted tree.
More on that next week.
Fall starts in late September and ends in late December.
For many of us however, "this time of year" is what we consider to be fall.
This time of year is the changing of the guard, so to speak.
Days continue to grow shorter and cooler.
Gardens are pretty well done growing for most of us
Fall clean up continues and of course, the colors that fall offers us.
Like the grand Grand Finally of a fireworks display, Nature offers us one last hurrah.
The end of another wonderful growing season.
A reminder to us all, that God is indeed in control.
You don't think all of these wonderful orchestrated events just happens do you?
Call it evolution by design (still creation).
Or call it what it is.............................
Like everything, it is to well orginized and planned out to just happen.
But, why and how does it happen?
Leaves changing colors that is.
I wrote about this last year, but it is well worth another mention.
Besides, we have several new readers.
Sit back and enjoy reading why leaves change colors.
If you are blessed enough to live in one of those parts of the world where ' Nature ' has one last fling before settling down into winter's sleep.
Count Your Blessings.
In those special places, as days shorten and temperatures become crisp, the quiet greens of summer foliage is transformed into the vivid autumn palette of reds, oranges, golds, and browns before the leaves fall off the trees.
On special years when conditions are right, the colors are truly breathtaking.
They have been spectacular this year.
How does autumn color happen?
As a child, I didn't care why they changed colors and parents and teachers would give a half correct answers.
As a Naturalist, I continue to grow more curious as to why certain things happen.
Fortunately, several have gone before us to study and research things.
Researchers and schools with all sorts of cool equipment and labs where they can research why leaves change colors and so on.
For years, scientists have worked to understand the changes that happen to trees and shrubs in the autumn.
Although we don't know all the details, we do know enough to explain the basics and help you to enjoy more fully ' Nature's ' multicolored autumn farewell.
Three factors influence autumn leaf color.
Leaf pigments, length of night, and weather, but not quite in the way we think.
The timing of color change and leaf fall are primarily regulated by the calendar, that is, the increasing length of night.
None of the other environmental influences...........temperature, rainfall, food supply, and so on-are as unvarying as the steadily increasing length of night during autumn.
As days grow shorter, and nights grow longer and cooler, biochemical processes in the leaf begin to paint the landscape with Autumn's palette.
Where do autumn colors come from?
A color palette needs pigments, and there are three types of pigments that are involved in autumn color.
Chlorophyll, which gives leaves their basic green color.
It is necessary for photosynthesis, the chemical reaction that enables plants to use sunlight to manufacture sugars for their food.
Trees in the temperate zones store these sugars for their winter dormant period.
Carotenoids, which produce yellow, orange, and brown colors in such things as corn, carrots, and daffodils, as well as rutabagas, buttercups, and bananas.
Anthocyanins, which give color to such familiar things as cranberries, red apples, concord grapes, blueberries, cherries, strawberries, and plums.
They are water soluble and appear in the watery liquid of leaf cells.
(Some birds rely on these colors for their bright feathers.)
Both chlorophyll and carotenoids are present in the chloroplasts of leaf cells throughout the growing season.
Most anthocyanins are produced in the autumn, in response to bright light and excess plant sugars within leaf cells.
During the growing season, chlorophyll is continually being produced and broken down and leaves appear green.
As night length increases in the autumn, chlorophyll production slows down and then stops and eventually all the chlorophyll is destroyed.
The carotenoids and anthocyanins that are present in the leaf are then unmasked and show their colors.
The timing of the color change also varies by species.
Sourwood in southern forests can become vividly colorful in late summer while all other species are still vigorously green.
Many species of oaks put on their colors long after other species have already shed their leaves.
These differences in timing among species seem to be genetically inherited, for a particular species at the same latitude will show the same coloration in the cool temperatures of high mountain elevations at about the same time as it does in warmer lowlands.
How does weather affect autumn color?
The amount and brilliance of the colors that develop in any particular autumn season are related to weather conditions that occur before and during the time the chlorophyll in the leaves is dwindling.
Temperature and moisture are the main influences.
A succession of warm, sunny days and cool, crisp but not freezing nights seems to bring about the most spectacular color displays.
During these days, lots of sugars are produced in the leaf but the cool nights and the gradual closing of veins going into the leaf prevent these sugars from moving out.
Under these conditions, lots of sugar and lots of light, spur production of the brilliant anthocyanin pigments, which tint reds, purples, and crimson of Sugar maples, Sweetgums, Ash and other species.
When conditions vary, colors will vary.
Because carotenoids are always present in leaves, the yellow and gold colors of Aspen and Black maple, remain fairly constant from year to year.
The amount of moisture in the soil also affects autumn colors.
Like the weather, soil moisture varies greatly from year to year.
The countless combinations of these two highly variable factors assure that no two autumns can be exactly alike.
A late spring, or a severe summer drought, can delay the onset of fall color by a few weeks.
A warm period during fall will also lower the intensity of autumn colors.
A warm wet spring, favorable summer weather, and warm sunny fall days with cool nights should produce the most brilliant autumn colors.
What does all this do for the tree?
Winter is a certainty that all vegetation in the temperate zones must face each year.
Perennial plants, including trees, must have some sort of protection to survive freezing temperatures and other harsh wintertime influences.
Stems, twigs, and buds are equipped to survive extreme cold so that they can reawaken when spring heralds the start of another growing season.
Tender leaf tissues, however, would freeze in winter, so plants must either toughen up and protect their leaves or dispose of them.
The evergreens-pines, spruces, cedars, firs, and so on-are able to survive winter because they were created to be tough.
Their needle-like or scale-like foliage is covered with a heavy wax coating and the fluid inside their cells contains substances that resist freezing.
The foliage of evergreens can safely withstand all but the severest winter conditions, such as those in the Arctic.
Evergreen needles survive for some years but eventually fall because of old age.
White pine shed year old needles, while some spruce etc. drop 2 or 3 year old needles.
The leaves of broadleaved plants, on the other hand, are tender and vulnerable to damage.
These leaves are typically broad and thin and are not protected by any thick coverings.
The fluid in cells of these leaves is usually a thin, watery sap that freezes readily.
This means that the cells could not survive winter where temperatures fall below freezing.
Tissues unable to overwinter must be sealed off and shed to ensure the plant's continued survival. Thus leaf fall precedes each winter in the temperate zones.
What happens to all those fallen leaves?
Needles and leaves that fall are not wasted.
They decompose and restock the soil with nutrients and make up part of the spongy humus layer of the forest floor that absorbs and holds rainfall.
Fallen leaves also become food for numerous soil organisms vital to the forest ecosystem.
Again, all part of ' Nature's ' Master Plan.
It is quite easy to see the benefit to the tree of its annual leaf fall, but the advantage to the entire forest is more subtle.
It could well be that the forest could no more survive without its annual replenishment from leaves than the individual tree could survive without shedding these leaves.
The many beautiful interrelationships in the forest community leave us with myriad fascinating puzzles still to solve.
Certain colors of leaves are characteristic of particular species of trees.
Some people plan their landscaping to go with the colors of fall foliage.
You may enjoy the warm colors of yellows, oranges and reds.
Or, you may lean toward the cool shades of Burgundy and purples.
Here is a basic list of trees and colors they can offer.
Oaks turn red, brown, or russet.
Hickories turn golden bronze.
Dogwood turns purplish red.
Beech turns light tan.
Red maple turns brilliant scarlet.
Sugar maple turns orange-red.
Black maple turns glowing yellow.
Sourwood and Black tupelo turn crimson.
Aspen, birch, and yellow-poplar turn golden yellow.
Leaves of some species such as the elms simply shrivel up and fall off, exhibiting little color other than brown.
Well, it's time to fly for now.
I hope you enjoyed learning a bit on leaves.
Before I go, here is your positive though for the week.
Life leaps like a geyser for those willing to drill through the rock of inertia.
This is very well said.
I believe what the author of this quote is saying is this............
a geyser builds up pressure until it has to release its steam and hot water, and release it with force.
Inertia, a physical body that persists in a state of rest until acted upon by an external force.
You are the external force working on an inert object (life) and life is the geyser.
While many people sit there waiting for life to happen, it passes them by.
They miss the grand opportunities that God had planned for them.
Get out there in dig in the rock and toil until you find life's joys and plans for you.
"Plan your work and work your plan."
Anything worth wanting or having is worth working for.
Planning for and heading toward you goals may require more education.
Maybe you will have to relocate.
If you allow fears and negative thoughts to get in your way,
You prove the fears right.
You prove to others that they were right, when they said you couldn't do it.
By moving forward, you continue to beat down the mountains that stand in front of you.
You will become an unstoppable force
Soon, the LIFE you want and planned for will gush out like a geyser.
Look out world, here you come.
An unstoppable force of good.
Now that is worth a huge smile.
Never allow another person say "you can't", "impossible", "you will fail."
You "CAN" "when you believe, it becomes possible"
"When you fail, fail forward"
Pick yourself up and press forward.
Start today by sharing your smiles.
You will live life to its fullest.
Go out and grab it, it wont come to you.
Until next time my friend.
"Treat the earth well:
It was not given to you by your parents,
It was loaned to you by your children.
We do not inherit the Earth from our
Ancestors, we borrow it from our Children."
Ancient Indian Proverb
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