There Is No Light Like That Which Shines

When the sun crosses that celestial plane to shine its favor on the Southern hemisphere, the pecan trees in my orchards are finishing their annual race. Their work is largely done. Inside their green shucks, the pecan kernels packed tightly within the shells are fully developed and are ripening. The fruit of our earliest variety, ‘Pawnee’ have already ripened to the point that the kernels are releasing ethylene gas, stimulating the shucks to split along their four sutures, freeing the nut from the shuck’s grasp.

               As the days shorten the leaves of the trees feel their age. We like to keep the trees healthy season-long so that the leaves will remain green and healthy for as long as possible into the fall. It is usually November before leaves in the orchard begin to change in bulk. Lower and shaded leaves are the first to turn. They do the least amount of work for the tree, shaded as they are, and are of less value. Even leaves exposed to full sun have lost about 40% of their photosynthetic capacity by now. The loss of just a few lower leaves at this time of year is of no more importance than our trimmed fingernails or the hair shorn from our heads. Pawnee, being a variety with one parent (Starking Hardy Giant) adapted to the northern part of the tree’s range, tends to lose its leaves earlier in the fall than varieties with a more Southern origin. But all living things take certain traits from each parent. For Pawnee, it’s southern inheritance is its early ripening date and narrow leaf and limb angles, allowing the tree a more upright appearance.

               The aging out of leaves on a tree is termed “senescence”, a process which happens to us all as the cycling of our cells slows, and the cells stop dividing but remain metabolically active. It is all a part of getting old. In trees like pecan, complex molecules in the leaves are broken down into more basic ones and are resorbed by the tree, wasting as little as possible and salvaging what it can for use the following year.

               But life, including the salvaging of resources for another year, always comes at a cost. The resorbtion of sugars and amino acids back into the tree’s perennial tissues requires energy. This means that the leaf still has work to do. But chlorophyll, perhaps the most magical substance on earth, being that pigment that turns sunlight into energy, is beginning to degrade. It can’t keep up with its work. The leaf becomes vulnerable to ultraviolet light, to pests and diseases still prowling around. This is when other pigments lying concealed beneath the dominance of chlorophyll appear and pick up the slack, giving the tree just enough of a boost of energy to resorb those resources, sustaining the leaves as long as possible into old age and providing stores for the future.

               There are several pigments that take up the baton from chlorophyll and run. These include carotenoids, tannins, and anthocyanins. The carotenoids give leaves their yellow and orange colors. They are present season-long but are overpowered in our eyes by the green pigment of chlorophyll. Behind the scenes they are working together with chlorophyll to absorb sunlight and assume this role to a lesser extent but more fully in chlorophyll’s absence. When we have dry falls without much rain, the yellow of the carotenoids found in pecan leaves is on full display for an extended period as entire orchards turn gold and the leaves drip slowly from the trees, allowing for maximum resorbtion of resources back into roots, trunks, and branches. When this occurs, there is no light like that of an orchard in November.

Tannins are also present in the leaf. They are considered a waste product of certain plant processes but tannins serve as a defense mechanism against pathogens or pests and microbes that might feed on the leaves. Also present throughout the growing season, tannins become visible only after the chlorophyll fades. Tannins often have a greater visible presence in wet autumns or later in the fall as rainfall favors physical damage of the leaf, disease infection, and more rapid breakdown of the leaves as the tannins oxidize.

The brilliant shades of red, purple, and crimson found in many hardwood trees come from anthocyanin. It is a less reliable pigment. The more sunlight a leaf is exposed to, the more sugar is accumulated in the leaf, and the more anthocyanins are produced. This leads to the red color of leaves found in some oaks and maples. Pecans also produce anthocyanins but rather than retaining them in their leaves, pecan concentrates anthocyanins in the seed coat of the kernel and in the shell, lending pecan nuts their high antioxidant content.

Each of these pigments, though hidden from the passing eye for much of the year, are always behind the scenes, doing their jobs. Only when the chlorophyll fades in the process of aging and senescence do these other pigments show themselves.

As the years pass, I become more interested in the process of aging. I am not yet elderly but I have enough years on me to think about such things. The way the body slows and vision degrades. Like the turning of leaves in the orchard, these are signs of change.  I used to give no thought to the changing of the seasons because when you are young, you take for granted that there will always be another summer. Later you realize that the seasons, like the years, are numbered. This has led me to try and slow down as much as I can to look around and appreciate each season for what it is.

Winter is the time of dormancy, of rest. Spring brings new life. Summer, here in the south can be long and insufferable but, that is when the good stuff happens. The soil is warm, the trees are fruiting, the land is breathing, and life is full.  Autumn, for me has always been a time of reflection. Looking at it as the tree does, autumn also becomes a time of preparation and a time of renewal in another way.

Like the chlorophyll that masks the presence of those other pigments that play such important roles, the summer of our lives often conceals from us the things we too often place in the background. We recognize their importance but as we go about the job of training and working and chasing goals, it is easy for these vital components of our lives, the true foundation on which the rest of it is built, to be overshadowed in our own minds, at least for a season.

The chisel of life and time that molds and shapes us into the people we become shaves away all the surplus, all the BS, the pettiness, arrogance, and pride we think we need while in pursuit of goals. If we pay attention to the lessons it teaches, life will sculpt us down to reveal the true self that was hidden in all that ambition. We let go of the things that don’t matter. The outer layers peel away, the surface degrades and we begin to recognize the people and things underneath that have been hidden within us all this time, picking up our slack. The things that do matter. The things that nourish and endure to sustain us into old age. If the layers are peeled down deep enough, maybe we too will have the opportunity to become one of those hidden, nourishing pigments for someone else. Along the way we may even find that investment in others nourishes us as well. Our hidden pigments include that spirit that forms the voice in our hearts, the people closest to us, family and friends. There are also ideas, ways of seeing, and words from texts and books long written down. And like the golden leaves of a dry fall, there is no light like that which shines from them all.