Some time in the next month, a desire for fall will seize you. On a Saturday morning the humidity will clear out, a leaf outside your window will turn to lemon, and you'll hop in your car and head west: out Rte. 66 to Front Royal, down 211 to New Market, south on Rte. 29 to Culpeper, off on the little roads, down by rivers or up on Skyline Drive. I know you will, because I've seen the traffic jams in Gainesville.

I'll be there, too, mind you. But as a veteran fall-watcher, I warn you, such days can go flat. You'll find that you've come before the oak leaves reached their prime, or after the tulip poplars have all fallen, or that the maples are dull this year, or the sky overcast and the colors dark. Even when the view is splendid, you will be bored after 10 minutes. You'll stop to buy cider and bird baths, and go on home.

But seeing requires a discipline. It's no good waiting to be overwhelmed by the show. You have to be there for something. Hunting works well, I understand, but I could never stand the blood. Photography is expensive, painting is hard, canoeing is risky.

Try identifying the trees. Utterly useless in itself, this discipline will require you to look -- really look -- at the things you have come out to see. Besides, if you are ever going to learn trees, this is the season. A woods in summer is an impenetrable wall of green. But fall brings out individual colors and shapes that can be recognized at 60 mph. Though a walking pace is better.

Hickories, for instance, are the glory of Virginia Octobers. You will recognize them by their deep gold color that turns brown at the edges late in the season, but they are no less handsome for that. And by their shape: tall, thin and irregular, like Roman candles. Hickory is a tree for the margins of a classical landscape. Up close, the leaves are compound, like walnut and ash; each leaf is composed of a bunch of little leaves (say five to nine) arranged on a stalk. But you won't get confused. The ash leaves become overlaid with purple and orange, not at all like the hickories. And walnut trees drop their leaves abruptly in September, the walnuts left among the bare branches, like nubbly green tennis balls.

Hickories have a nut, too -- dark brown and not much bigger than an acorn, and not much better to eat. The most widespread local species is called "mockernut" hickory, presumably from disappointment. Squirrels like them. The husks last for years and litter the ground under a good-sized hickory.

Sugar maples turn early in the season, usually near the beginning of October, and a little later closer to the mountains. Though not as glorious here as in New England, sugar maples are marked by the intensity and translucence of their color: yellow, yellow and orange, or yellow and red, changing to a wash of watercolors before they fall. Red maples also turn in combinations of color, but their leaves are opaque, as if someone dabbed a brush of dense color here and there. The silver maples that blanket the suburbs are green through most of October, before their finely cut leaves turn to bright lemon.

For sheer brilliance of color, you can't beat tulip poplars. Don't confuse them with hickories. Poplars are the other huge yellow trees, but lighter and brighter, their shape altogether different with a wider bottom and, when they grow in the open, a perfect Gothic arch at the top. The leaves fall gradually, leaving behind a pointillist texture, 10,000 bright yellow dots on a dark ground. Slowly, the Gothic arch is revealed and, toward the end of October, husks of the tulip-shaped flowers, little circles of seed pods with wings, show themselves.

Then there are the lesser yellows. The beeches, though noble trees for size and form, turn an undistinguished yellow with brown along the edges. You know them by the smooth gray bark carved with initials. Sycamore leaves turn a yellow mixed with green, and are also best known by their bark, which flakes off in great patches, leaving white scars. The sassafras,a small native tree of mitten-shaped leaves and pungent twigs, turns mainly yellow. And a tree you may think is a maple because of its elegant, star-shaped leaf that turns yellow and purple is a sweetgum.

Some years, a deep winey purple seems to be the color of choice in the long Virginia autumn, as if the landscape were drenched in burgundy. This is the color of dogwoods, persimmons and mulberries, and lots of scrubby and straggly shrubs of the field and undergrowth. And it's the color of the ubiquitous sumac, the weed of open country that lifts up grape-like bunches of small, dark red seeds.

As October eases into November, richness seeps into the oaks, which are in no hurry to get on with the deciduous business. Different species of oak turn many different shades, some toward red, some toward bronze, a few just brown. But they all hang onto their leaves into November, and a few long enough to rattle in January winds.

There is a true red in Virginia. You find it on back roads, one tree at a time. You would never notice it in summer: small, shaped like a tree should be, but with leaves like long almonds. Its early October red is like fire. Travelers in cars exclaim, "What was that!" A sourwood tree is not much for lumber, not much for wildlife, not much for landscape. Autumn has its own hierarchies.

Autumn also has its seed pods. When leaves fail to identify themselves, sometimes grotesque ornaments that carry seeds will do instead. Black locusts sport thick bunches of long, narrow pods. Honey locusts are more bizarre, with huge banana-like pods that hang high in the air. If you can reach to gather a few -- watch out for thorns -- the seeds inside are a beautiful dark glossy brown and pleasant to the fingers. Locusts are legumes, like peas and beans. So is the catalpa, which carries the longest, skinniest pods of all, while its huge heart-shaped leaves simply drop without changing color.

The hornbeam, a bushy little tree that favors stream bottoms, reaches out over the water with strings of brown pods that look like tiny Japanese lanterns. And the misnamed Tree of Heaven is a weedy import that grows along roadsides, looking ridiculous shorn of everything but great popcorn balls of brown papery stuff by late October.

That's enough to make one trip a fall. If knowing trees helps you to see autumn, maybe you'll recognize them as old friends in spring. Seeing has no season.