Sunday, October 16, 2011
Fall Leaves Fall...
Autumn is sublime. The days shorten, which lengthens the mood filled night. The air grows crisp allowing us to enjoy the pleasure of a cozy sweater. We are allowed to bear witness as nature passes into a form of hibernation for the winter months to come. For a couple of months out of the year, we are able to witness what I find to be nature at it's most beautiful. Gaia produces her palate and colors the trees in an array of vibrant and muted shades. She plays us the meditative melody of Autumn breezes swirling chaotically around and through branches and leaves, making the gradually changing flora whisper against each other. Autumn is about sipping a piping mug of cocoa while watching the leaves dance their way gracefully to the ground. Autumn is about throwing on a warm jacket and scarf, strolling along quiet paths while listening to the dull crunch of leaves under your feet, and feeling the soft breath of the wind play over you. Many forms of life may be preparing for winter slumber, but it is during this time that I feel the most alive. I love these Autumn months, and I am so glad they are finally here.
As many people do in various places, Autumn drives are a kind of ritual. Hopping in the car on an autumnal Sunday, and heading out in search of lands more bucolic to see the changing Autumn leaves. At least I think the traditional day for leaf viewing trips is Sunday. I haven't broached the subject yet here in the homestead, but I believe I can safely say that a Sunday drive won't happen any time soon. It's football season. Personally, I don't care much for the sport (I dig hockey), but me thinks an Autumn leaf viewing drive will have to take place during the week. I could venture out on my own to look at leaves, but what would be the fun in that? A day will be scheduled, pictures will be snapped, and then pictures will be posted. Stay tuned...
Since I have been blathering about Autumn's leaves, I feel the need to get a little botanical and add a section on why leaves change color during the Fall. Going back a bit to the Science Classes of my youth, the leaf changing process starts with a process you might have heard of (*grin*) called Photosynthesis. In case some memories need refreshing, Photosynthesis is a chemical process that happens in plants. Water, carbon dioxide, and sunlight are used to create 'food' for the producing organism, usually in the form of sugars. The waste product? Oxygen, which is pretty important to us humans. Now for the green portion of the equation...Chlorophyll. It is vitally important in Photosynthesis, as it is the key component in obtaining energy from light. There is a wealth of extremely detailed information on Photosynthesis and it's many nuances, but I am going to keep my explanation short and sweet to get back to the main focus here.
As you know, Spring and Summer are rife with greenery. The reason for that is the days are longer, so there is more sunlight during an average day. That sunlight is what keeps the leaves green due to the dominant presence of Chlorophyll, which over powers and masks other colors from being produced.
Then at the end of September, Autumn officially starts and we see the days shorten. Shorter days = less sunlight. As the days shorten, there is less and less Chlorophyll. Simultaneously, as the Chlorophyll is decomposing (a process that is at a constant which causes the green leaf color to fade) there is a surge in sugar production. The higher concentration of sugars causes an increase in the production of Anthocyanin pigments. A leaf that contains primarily Anthocyanins will appear red in color. (Ex: Maple leaves commonly turn red due to high levels of glucose trapped in the leaves.)
Another pigment that can be found in some leaves is called a Carotenoid. Carotenoids are not dependent on light, so production doesn't diminish due to the shortening of days. These leaves can be yellow, orange, or red. However, most Carotenoids are found in yellow leaves.
If a leaf has a high concentration of both Anthocyanin and Carotenoid pigments, it will most likely be red.
There are leaves that may have an absence of the two pigments, which allows other chemicals to work their magic. For example, Oak leaves create a high amount of tannins as a waste product. Those tannins produce a brown color.
As we all know, with the shorter days of Autumn comes cooler temperatures. Temperature can effect chemical reaction rates, but the main part of the 'leaf color change' equation is daylight. If an Autumn is filled with mostly sunny Fall days, then you will see more bright colors like reds and oranges. If an Autumn is filled with overcast days, you will see more browns and yellows. This concludes today's lesson...there will not be a quiz. (*grin*)
While I was doing my usual snooping around on the 'net', I found a cool site that caters to people who like to view Autumn leaves. The site has a list of "foliage cams" with live feeds from Canada to North Carolina. If you are a "Leaf Peeper" (that's what they call people who like to view Autumn leaves...sounds kind of pervy) and want to check out leaves in other places, then this is the site for you. Just click on this link.
Happy leaf looking!