OUTDOORS: CHANGE OF COLOR ONE OF NATURE'S IRONIES

Leaves are their most bedazzling in death.

It's ironic that we most appreciate the foliage of deciduous trees -- those that shed their leaves each year -- when that foliage is perishing. It's when the leaves are on their last legs, however, that they best exhibit nature's paintbrush with a gaudy display of colors ranging from smoldering golds to riotous reds.

Leaves aren't really green, actually. Most of the year, we see green, but that's a tint job like so much Lady Clairol. It's really chlorophyll that's green, and chlorophyll is the stuff that dominates the look of foliage while the leaves are doing the vital, everyday work of photosynthesis -- soaking up energy from the sun and turning it into food to feed the trees.

We enjoy the benefits of photosynthesis, for the process absorbs carbon dioxide from the air and gives off oxygen, the object of our respiration. Without green vegetation making the stuff, in short order we'd be sucking wind in vain.

Anyhow, chlorophyll is a pigment that is present during photosynthesis. It masks the other colors that are present in leaves. When the period of cold weather dormancy approaches, however, chlorophyll breaks down, curtailing photosynthesis. The trees then begin to lose their masking green makeup and the other pigments start showing through.

The result: autumn colors.

Sadly, the transition between the green of summer and the dirt brown of winter is a relatively quick one. By mid-November, it's pretty much a done deal. The short while between mid-October and the brown-out is one of the finest shows nature produces.

Ideal conditions for the maximum of fall colors are warm days and cool, crisp nights. Those elements allow more sugars to be trapped in leaves, and these produce more of the brilliant shades that are most appreciated, the reds oranges, purples and golds.

Some species of trees are more prone to be show-offs during the autumn. Sugar maples, red maples, sweet gums and dogwoods can be particularly wild with and array of the reds, oranges, purples and golds.

One doesn't have to be a botanical expert to pick out a sumac, a shrubby little tree, from a half mile away. Right about now, sumac leaves are blood red and stand out like a beacon among limbed neighbors along roadways and fields.

Hickories likewise stick out like towering sore thumbs along timbered hillsides. Mixed in with still-green oaks, the hickories -- shagbarks, shellbarks, pignuts and mockernuts -- are a flaming yellow gold. A squirrel hunter who seeks a nice hickory under which to perch doesn't have much of a chore picking one out right about now. The oaks, which are rather modest on color display, are stubborn. They cling to their green far longer than many species.

Some, like the green ash, are more anxious to get it over. The ashes typically will have their leaves turn pale yellow, brown up, then drop to the ground before the average oak tree makes a color move at all. By the time oaks start seriously turning, the ashes already are as naked as jay birds.

The tree candidate for most disappointing might have to be the silver maple. It hints at a color effort, the leaves starting to go yellowish, then it gives up and starts ditching the foliage, which quickly goes to dull grayish brown. If trees had personality, silver maples would be dull and short on conversation.

A year-after-year favorite? The sweet gum, a tree with flair. You never know, but it's going to give you something nice in color when the chlorophyll bugs out. Maybe shocking red, maybe tangerine, perhaps deep grape -- and possibly all those hues and more at the same time.

Trees may be enduring the death of their foliage, but before the bleak days of winer, we can appreciate those species who go through the transition with style.

Steve Vantreese is outdoors editor of The Paducah Sun.