Fall Colors in Appalachia

Most people in this region look forward to the fall more than any other season, despite this being the prologue to winter. Starting in September at the atlas or far end of Appalachia, color changes ripple down the spine to the coccyx at the southern extremity a month later, but the finest sights are in the north and at high elevations. Colorful sugar maples like it cool.

Fall colors in Appalachia

People have probably marveled at the spectacle ever since they first set eyes on it eons ago, and long before they wrote about it. I find it perfectly understandable if Native Americans believed fall beauty was the deliberate artistry of a Great Spirit who painted the trees, flowers and creatures for human pleasure, like the Huron story of a great bear’s blood dripping on the forest from heaven and other stories passed down in tradition and lore. More than anyone else, Charles Darwin deposed humans from the center and purpose of creation, but accommodated his feelings for natural beauty in an evolutionary perspective (‘There is grandeur in this view of life …’), which is surely true though we have paid a price by losing a naïve and supremely arresting joy out of mystery.

When the first people saw the Appalachian Mountains there were no trees because the land had been scraped by glaciers and it took centuries for forestland to replace retreating plants that were the first colonizers after the last Ice Age. We are lucky to live in an era when conditions favor trees with fall splendor, though probably one of the last generations to witness them as climate warming pushes back the season and trees struggle with summer heat. The change is not so much a loss to the tourist industry as to the human spirit.

This year’s weather has muted fall colors in Central Appalachia. The maples were almost denuded a month ago, although the oaks are still green and beeches golden-yellow.

Leaf color chemistry is molded by weather. For the most brilliant display, summers should have plenty of rain because drought triggers leaf abscission. Then, late summer should have warm, dry days and cool nights with little wind. Those conditions prevailed this year, save one—the nights stayed mild. We had our first frost on October 17, but it was slight and night temperatures were mostly above average. An Indian summer spoiled a painted fall.

The closer you look at leaf chemistry the more complicated it seems. This is surely a principle in science as, for example, whether physicists study elementary particles or the cosmos the closer their examination the deeper and further they are borne. Science mines nature, but we never get to the end of the seam. We celebrate this richness, but it must be frustrating for politicians who commission research because they hope complexity will turn into neat answers, yet at the end of a study the conclusions are often provisional and there are plenty of new questions.

Once upon a time, fall colors were regarded as consequences of healthy biochemistry yielding to organic decay. The fact of the matter is half opposite because they involve a rather active process. Some genes switch off while others turn on. Each leaf is more in command of its fate than left to the consideration of entropy. Of course, photosynthesis does shut down in the absence of enough sunshine or moisture, and, to add complexity, deciduous leaves are more responsive than evergreens. It’s a familiar story because a sun-loving pot plant left in a shady place when we go on vacation will be a pile of dry leaves and bare stems when we return. It is a protective mechanism for plants and deciduous trees in autumn to withdraw vital nutrients and minerals from leaves into their ‘body’ for storage until needed at the start of the new growing season when the sun breaks out.

When the green pigment disappears, the yellows and oranges that were present all along are revealed. Beech leaves go a step further when the pigments turn into brown tannins that we notice dangling on stems all winter. But the red and purple pigments of maples and gums are synthesized de novo shortly before their leaves fall.

These are anthocyanins, which are molecules that are abundant in ripe berries and grapes and lend red wine its virtuous reputation. They are beneficial for leaves too where they serve as sunscreens and antioxidants to protect valuable molecules synthesized in the summer from solar rays shortly before the fall. There is another theory that bright colors warn away pests, as if rouge leaves can tell insects they ought to buzz off to find a less vigorous tree. It doesn’t square with the widespread lack of receptors needed for seeing red.

Despite its brisk pace, I believe science will never end and its ambition will never find a final goal. That’s worth celebrating. Life would be boring, almost pointless, if everything was predictable and nothing was mysterious. Mystery is sacred.

Fortunately, there are still countless enigmas in nature to stimulate our curiosity, and keep scientists employed. In this post I can mention only one, though it is relevant here. I wonder why evolution hasn’t given all deciduous trees the same glorious reds and purples in the fall if those pigments are so beneficial. Isn’t natural selection supposed to steer genetics to an optimum fit for the environment? Europeans must be satisfied with their yellow fall leaves and no native reds at this season compared with the hot colors we enjoy most years in eastern North America and Asia. Are there any bright theories out there?

Autumn Leaves have Fallen

I remember leaves falling precipitously in Quebec during September when the sugar maples create a blazing mosaic of gold and ruby on forest floors.  But the first snow blots over the colors as it quietly descends layer on layer with few melts over the next months. But here in south-east Virginia fall doesn’t arrive until late October, and then comes on hesitantly, one tree species shedding after another until Christmas, and snow is a stranger.

bronte-poem

Fall is the first love of Quebecoises, but they have more passionate ardor for the first cold kiss of winter when their skis are brought down from attics to wax for the slopes and forest trails. Virginians love their long colorful season, although if you ask gardeners you might hear them groaning.

Lawns turn from greens to browns, and flower borders from dainty asters to crinkly blankets. It is the time to pull rakes out of garden sheds and turn on leaf blowers, which will roar for weeks around the neighborhoods. The red oaks keep their canopies until shortly before Christmas, and if I go outdoors after a windy night I have to tramp through leaves deep and crisp as cornflakes after a tremendous dump. Then the rake comes out again.

I estimate over 50 million leaves fall on our property. Only beech stays covered until spring buds nudge them off. Every species has its reason, except the human kind which has a perverse attitude to leaf fall.

Although the season is now long past, serried ranks of 40 gallon plastic bags still wait at the end of driveways to be carted off to the county dump. Trash to most people, they are bags of treasure to me.

The first neighbor looked puzzled when I asked for his bags, and then curled a smile. “Why sure. Go ahead and take my other trash and a dead animal too.” I didn’t ask others after that. I just threw their bags on the back of the truck, hoping they would be pleased to see an empty driveway.

The leaf thief
The leaf thief

I brought home 75 bags of dry leaves which, on average, weighed 40 lb (18 kg) for a total of some 3,000 lb or 1.5 short/ US tons (slightly less in Imperial tons). Wondering how many leaves I collected, I counted a sample of 1,000, which weighed about 1 lb. According to rough estimates, my haul rounded up to 3 million leaves, but that didn’t include the countless number I raked in the yard. According to an agronomic library used by the Druid’s Garden to estimate chemical composition, I brought home 1,500 lb carbon, 48 lb calcium, 30 lb nitrogen, 7 lb magnesium, and 3 lb each of sulfur, potassium, and phosphorus. Why, you might ask would a leaf millionaire want more? And what makes him a scavenger?

Taking away leaves has the same impact as cropping. It depletes the topsoil of precious minerals and removes carbon captured by trees during the warm months. Returning their goodness replenishes the soil by making chocolate humus. It avoids the need to buy chemical fertilizers to feed the ground and mulch to protect flower beds because dry leaves look attractive, and of course natural, in a woodland garden.

In the right places they are beneficial in every way, and over time they restore soil fertility where it was impoverished by hungry crops, like tobacco which was grown here as a former plantation. Leaves that are not spread around are pressed into leaf bins and baskets to make leaf mold, but they are placed far from tree roots that would try to suck out the nutrients. Black walnut is the only unwelcome species because every part contains toxic juglone.

If practical arguments leave you cold then consider picking a leaf for meditation. To paraphrase William Blake’s Auguries of Innocence: “To see a world in a bunch of leaves, And heaven in a green leaf…” Leaves capture carbon, exhale oxygen, transpire water, recycle minerals, provide food and shelter for the “little creatures who run the world” (E.O. Wilson), and of course they feed nations with nutritious chow and inspire us with color.

Next Post: My Hunt for a Hellbender

Glycerinate Fall Leaves

Here’s a cheapskate suggestion for decorating the table at Thanksgiving or giving at Christmas to people who have everything. Fall leaves!

While other families in the neighborhood are filling bags with leaves from their yard for collectors to cart away to the dump, I am spreading them evenly into the flower beds to save the cost of mulch, but I bring the most colorful and perfect specimens indoors.  Southern red oak, tulip poplar, dogwood, beech, and sweet gum—all changing through a spectrum of bright colors, and each keeping to its peculiar schedule.

Wouldn’t they look great in a bowl on the festive table if it was possible to stop them curling, cracking, and crumbling? It is, in the twinkling of an eye.

  • Dilute a bottle of glycerin (glycerol) from the pharmacy with tap water in the ratio 1:2
  • Pour the fluid into a tray for soaking the leaves
  • Flatten the leaves with a weight (like a matching tray)
  • Allow them to soak for a week or so
  • Pour off the fluid and dry the leaves on paper towels
  • Voila!Glycerinated fall leaves-small

The glycerin helps to preserve the leaves, and makes them supple. They should last until springtime when delicate, lime-green beech leaves attached to their branches can be gathered for glycerin treatment. That makes a cheerful decoration for the fireplace when it becomes vacant after the winter, and is a recipe I learned from a country gardener. Mum’s the word.

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