I know, I know it’s so that we better utilize the diminishing light, so school children are not invisible to the buses that gather them up each morning, so that I can see the hand at the end of my arm letting my chicken out each morning before I set off for my day, but I don’t like it.
I miss seeing my trees change.
I know the science behind the magic that dances fuchsia across the edges of my witch hazel’s foliage like a child playing with lipstick, but I prefer to enjoy the unfolding color craziness as if watching someone transforming my yard each day with a drunken paintbrush flinging paint. I watch the Nyssa sylvatica dance a scarlet exhibition of release as the wind stretches leaves from horizontal branches like splayed fingers. Look, there’s a viburnum with a somewhat heart shaped leaf which is still green, but which has had its veins crimsoned as if to show its each beating breath. This is the most extraordinary of metamorphosis, a poetry of color and transformation, and this year has been the most spectacular show we’ve seen in as long as I can remember. And I want to see it happen.
Luckily I work at a place where I am surrounded by trees. And this year the Japanese Maples at Marders as giving a master class in the science of fall foliage.
There are three factors that influence the way, the rate and the intensity of foliage changes as it kisses goodbye each year, and although I would like to attribute it to witchcraft or wizardry, it really is simple chemistry.
The first factor is the shortening of the light due to the longer nights of fall. These shorter days, this limited light, and the cooler temperature that accompany the season’s longer, darker evenings, tell the trees that winter is coming and it’s time to slow down the production of food.
The trees are not changing colors, that’s actually a misnomer, instead they are actually stripping away parts of themselves to reveal what has always been there, but has been invisible to our eyes.
The pigments, the second factor in fall’s rainbow dance, the colors we associate with fall have actually been there all along; it’s just that for most of the year they are camouflaged by the leaf’s chlorophyll. Chlorophyll, a chemical cousin of hemoglobin, is the vehicle that transforms sunlight into sugars to feed my trees. The sugar that will keep my trees alive while they stand naked in my yard through the long winter darkness. During the rest of the year, the green of chlorophyll overpowers the carotenoid pigments that leaves contain as well. Carotenoids are primarily yellow and orange – the guts of a carrot or a butternut squash, and they too contribute to photosynthesis. They’re also the reason the palms of my hands turned orange the year I had a yam for breakfast everyday!
In the fall, as the nights lengthen and cool, chlorophyll production starts to slow, and then comes to a stop -- as the leaves realize there’s no more need to gorge on the sun. As they realize they are sated with sugars, eventually all the chlorophyll in a leaf disappears and it’s inner carotenoids are revealed.
Both carotenoids and chlorophyll are always present in leaves, but in the fall there are other phytochemicals produced called anthocyanins. Triggered into production by those huge stores of leaf sugar, these pigments present themselves as red, purple or blue depending upon the ph of plant.
(Thus in another application, the alchemy of hydrangeas morphing pink or blue based on the addition or subtraction of lime or sulfur.)
Anthocyanins are the blueberry stains on children’s lips and the kiss of plum juice and bruise of Concord grape skins. They are light-attenuators, and protect the leaves against sunburn. The combination of anthocyanins and carotenoids is species specific so as the chlorophyll robe of each leaf is dropped, the negligee of each tree is revealed. Clethra and ginkgos are golden; the burning bush is an obvious red. One of my varieties of crape myrtle turns a luscious, fudge rich maroon, while another is clear, vivid vermillion. Within a species there is incredible variation, as expressed so brilliantly each year in six different color that garb the enormous Japanese maples that embrace my father’s house on the corner of Palmer Terrace and Main.
What makes each year different, and what has made this year so spectacular however, has been the weather, specifically the temperature and the rain. All these warm days with cool, cold, but not freezing nights have triggered enormous sugar production during the day, but with the cool nights constricting the veins of the plants and preventing the sugars from leaving the leaves, there is a larger than normal production of the anthocyanins. Add in our cool summer, which allowed the soil to stay moist from spring through fall and we have the makings of a magnificent display.
A display which I am missing each evening when I get home.
Fortunately at Marders there’s a gathering of Japanese Maples (that’s my official horticultural term -- like a pod of whales, or an exhalation of larks) that are so spectacularly colored it’s like we cheated and stole chunks of the sunset we watch each night as the darkness descends and tied them to the bare branches of the trees.I cannot capture the colors on my cell phone of either the changing sky or the trees.
I get close but the camera keeps adjusting to compensate.
And in some ways that’s actually a gift.
It makes me watch each and every sunset.
To really look at all the variations of each leaf of each tree.
It forces me to truly see.
Paige Patterson has only one chicken left who is so traumatized by the disappearance of her sisters one by one that she no longer lays eggs. Sigh.
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