The three green ash trees right out my front door are nearly nude now. The ash leaves give up earlier than most and go from green to ugly to the ground in a hurry early every fall.

Mine are store bought, grafted trees of the Marshall variety planted years ago and I just don’t know if that has any bearing on the early leaf drop. But it is getting close to fall color and leaf raking time for all non-evergreen trees.

Leaves turn from green to the fall hues because the green stuff goes away, not because red or yellow or brown suddenly moves in. The same natural chemical combo called chlorophyll that uses sunlight and carbon dioxide to create sugar and oxygen also makes leaves green. Chlorophyll green dominates all other color pigments as long as day length and temperature keep it active.

As sunlight gets weaker and shorter in time, chlorophyll gradually plays out for the year. The pigments that provide fall color were there all along, but now get a chance to show their stuff. And residual sugars left behind enhance some pigments, making them more vibrant.

Weather is the big variable that determines how nice fall color is going to be each year. The best fall color follows nicely-spaced spring and summer rains, sunny fall days and cool fall nights. A year like this one with weekslong dry spells in the summer followed by overdue tropical storm rain is not the best for good color change, but we’ll soon see.

By the way, the ideal conditions needed right now for leaf color are “warm” days with temperature highs in the 60s and nighttime lows from freezing up to about 50. We usually don’t get those kinds of temps here the first half of fall. That explains why places known for fall color touring are in New England states, the Appalachian Mountains and wooded slopes of Colorado. Around here, an occasional super colorful fall will get some of us driving country roads within 20 miles of the house.

Along our wooded roadsides the trees most dependable for fall color include the various hickories, red maple, dogwood and sweet gum. Black gum and beech trees are even more colorful but less numerous. Bald cypress is fairly constant with autumn rusty red color. The most colorful of the oaks are not real common in natural settings hereabouts, including scarlet oak and chestnut oak.

Based on weather again, some red oaks such as pin, willow and shumard can be very colorful. In manmade landscapes, certainly the gingko tree is a colorful one, along with crepe myrtle, Japanese maple, Chinese pistache and Bradford pear.

Back before I purposely chopped it down, there was a vine that covered up an oak trunk near the future house site and in right-weather years it would turn gorgeous blazing red in fall. It was poison ivy, which is listed in numerous books and online sites as one of the most colorful of plants in the fall.

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Terry Rector writes for the Warren County Soil and Water Conservation District, 601-636-7679 ext. 3.