It’s Autumn And The Leaves Are Changing Colors
Les Harrison is the Wakulla County Extension Director
One certainty with Mondays in autumn, about half the college football fans are uncomfortable with seeing certain color combinations. Luckily, nature provides area residents with many pleasant options not associated with the recently lost games.
Wakulla County currently has many wondrous colors in the leaves of plants and trees which indicate the autumn season at its best. The color and shade indicates the plant species and the season’s progression.
While there is still plenty of green being produced by pines and palms, other deciduous plants are displaying reds, yellows, purples and browns. Deciduous plants are those which lose their leaves in winter.
Leaves are green because of the chemical pigment chlorophyll, which is plentiful in summer and the dominant compound. This substance dictates the appearance of the leaf during the growing season, but the foliage’s chemistry is far more complex.
Chlorophyll is critical to plant’s health and growth during the warmer months. It is the chemical catalyst which converts energy from the sun and nutrients into sugars which the plant or tree uses.
Trees and plants produce and consume chlorophyll throughout the growing season. The robust green coloration is a sign that it is healthy and functioning to its fullest capacity.
As summer passes into fall, the cooler temperatures and waning hours of light each day cause plants to constrict their veins and lower the availability of chlorophyll. The plants vascular system which carries fluids into and out of the leaves is gradually closed off by a membrane layer at the base of each leaf.
As the seasonal transition progresses leaf veins will remain green as the other leaf tissues change color. The color and intensity depend on the species of tree or plant.
Carotenoids, which reveal their presence by orange and yellow hues, appear gradually.
Hickories and pecans, which are in the Carya genus, have distinctive yellow leaves.
The reds and purples come from another pigment group called anthocyanins which reside in the cells. This chemical compound develops in the sap of the leaves.
These pigments are not present in the leaf during much of the growing season, but are quickly produced in August and September. The amount and intensity of the reds and purples in leaves depends on a combination of environmental factors.
The breakdown of sugars, the intensity and duration of sunlight and the level at which phosphate declines in the leaf combine to produce a nearly infinite number of shade and hue possibilities.
The brightest colorations commonly occur when the fall days are bright and cool, and the nights are cold but not below freezing. Sweet gums, Florida maples and dogwoods all have red to maroon range leaves.
Both creeper and poison ivy are bright cherry during the waning days of autumn. Sometimes with the loss of leaves, it is difficult to tell the two species apart.
Unfortunately for anyone who physically contacts poison ivy leaves, red or green, they prove to be equally itchy.
While the season may change the color, the result, in this case are just as uncomfortable