"If you like your Fall colors intense and vibrant, you've come to the right place," said WW&W Fall foliage correspondent, the lovely and colorful Autumn Equinox. "And who doesn't?" she asked, "except for local fundamentalists who think our gorgeous color makes the leaves look like they're wearing makeup, a sin in their black-and-white world."
"They don't like it when the wind rustles through the trees either," WW&W wildlife correspondent Paris Hiltunen added dubiously, "because it makes the leaves look like they're dancing; even Mother Nature knows better than that, she likes waltzing to the Copper Country Anthem."
"Fortunately, they're a minority exception, an aberrant statistic," Autumn added, "most people are interested in how leaves change color. A green leaf is green because of the presence of a group of pigments known as chlorophylls," she continued, undaunted by dogma. "When they are abundant in the leaf's cells during the Spring and Summer growing season, the green color dominates and masks out the colors of other pigments present in the leaf."
The chlorophylls perform a vital function: they capture some of the sun's energy and utilize it to manufacture the plant's food, simple sugars produced from water and carbon dioxide are the basis of the plant's nourishment, the sole source of the carbohydrates needed for growth and development.
In their food manufacturing process, the chlorophylls break down and are continually used up. During the growing season, however, the plant replenishes the chlorophyll so the supply remains high and the leaves stay green.
"My influences both inside and outside the plant cause the chlorophylls to be replaced at a slower rate than they are used up. With the total supply gradually dwindling, the masking effect slowly fades away. Then other pigments present in the cells all during the leaf's life begin to show through. These are carotenoids, giving us colorations of yellow, brown, orange and hues in between."
The reds, purples and their blended combinations that decorate Fall foliage come through another group of cell pigments called anthocyanins, not present in the leaf throughout the growing season, but develop in late summer in the sap in the cells of the leaf. Their formation depends on the breakdown of sugars in the presence of bright light as the level of phosphate in the leaf is reduced.
During summer, phosphate is at a high level and has a vital role in the breakdown of sugars manufactured by chlorophyll. But all in all, phosphate along with the other chemicals and nutrients, move out of the leaf into the stem of the plant, changing the sugar-breakdown process, leading to production of anthocyanin pigments. The brighter the sunlight during this period, the greater the production of anthocyanins and the more brilliant the color display we see.
"When my days are sunny and cool with nippy nights, the brightest colorations usually develop," Autumn articulated. "Anthocyanins temporarily color the edges of some young leaves as they unfold from the buds in early Spring," added Autumn's twin sister, Verna Equinox, universally known as the 'Queen of green'. They also give the familiar color to cranberries, blueberries, cherries, strawberries, plums and apples."
"In sister Autumn's northern boreal forests they show up vividly in maples, oaks, sourwood, sweetgum, dogwood, tupelo, black gum and persimmon, often combining with the carotenoids' colors to produce the deeper orange, fiery reds and bronzes typical of many hardwood species, including the burning bush with flame-red of biblical proportions, which you'd think fundamentalists would appreciate."
Now that you know what makes our fall foliage so fabulous, you don't have to go far to see it in all its glory. For a color tour that takes the cake, take a WW&W CCCC, Copper Country Color Cruise, from Dollar Bay to Dreamland, take in the panoramic birds-eye view from the toppa Bumbletown Hill at the Keweenaw County line, or drive through the canopy of color along the Covered Road to Redridge and the northernmost stretch of US 41 to Copper Harbor. If you're feeling adventurous, take the scenic route Autumn and I travel, the Triple A Road backa L'Anse Vegas through the Huron Mountains from Big Eric's Bridge to Big Bay.
Jim can be reached 24/7/365 at jjunttila@ chartermi.net.