Thirteen-year-old Alex Corning, a two-time champion pony jumper, is on her way to becoming a real horsewoman.

Photo by Randy Tunnell.

Several images stand out in my memory of last year''s Pebble Beach Equestrian Classics: a water-smooth rider in the Jumper Derby; a Kennedyesque clan eviscerating their rider''s performance, and then hushing as that flushed, worried young man rode up on his lathered mount; and a gaggle of girls about 10 years old in their breeches and black riding helmets, one of whom led a pony with a green ribbon on its bridle.

The girls stopped in front of us and leaned on the rail in the sun to watch the Derby jumpers, giggling and chattering. They were tan and golden, tiny and quick. As they talked they tried on the affectations of older girls, standing with hips stuck out to one side, their heads cocked in miniature parodies of sassy adolescence. Shortly some sixth sense called them and they left behind the dull, immobile grownups in their sunglasses to seek certain excitement in some other part of the grounds.

Meanwhile, the women they will become took their turns around the ring, urging their expensive horses over the double oxers, setting their jaws and whapping their mounts when the horses veered and refused the jumps. Almost without exception the riders were coldly beautiful, with hard faces and absolute focus. Girlhood horse-craziness had sobered into a tough business. The animals were now partners to be negotiated with, not pets to be spoiled.

Watching them will their horses over the fences, I was reminded that in the executing of any dream, the dreamer is changed. The stars fall, the blossoms drop. Work and striving take their toll.

But there is a moment before the course is set, when play is just beginning to be tinged with work, that is new and green and wide open. Alex Corning inhabits this moment.

At 13, she is the quintessential child on the brink-already tall, a featherweight with a light dusting of freckles and limpid blue eyes. She is wearing a dark blue sweatshirt, breeches and riding boots. She moves her narrow body through space via the slightly awkward gait that is the hallmark of nice, quiet girls who are taller than their peers. An enormous riding helmet completes the impression that somehow, in her in-betweenness, she is not quite of this earth.

Walking beside her at the end of a set of slim dark reins is a dainty 9-year-old Morgan mare. The pony turns her head from side to side and works her mouth as if talking to herself. Slowly the two walk toward the arena in the early afternoon that is only now rousing itself from a Pebble Beach fog.

Alex does not waste words. But in a genuinely polite way, she answers questions about Pixie, whom she leased three years ago and later bought.

"She was a carriage pony," Alex says. "She had to do hunters at first, but she was too fast and now she does jumpers."

In the hunter classes, horses are judged for style and form as they canter around the ring and jump fences. Alex explains that in hunters, "everything has to be perfect-lead changes, everything. And also the judges don''t really like Morgans. They don''t think they move so well."

This has not lessened Alex''s opinion of Pixie. Her mother, who also rode as a girl, says she saw Pixie and knew she had to have her. "She''s got a great heart," Alex says, scratching her pony''s neck. "She''s so cute and nice, and she has great ground manners. I wish Morgans got taller. I would keep on riding them."

The problem is that not only will Alex undoubtedly grow taller herself, eventually requiring a bigger horse, but she will also grow braver and more skilled. The jumper classes, with their height and speed requirements, have worked their way into her blood.

"You get timed... it''s just better. You have more fun," she explains with a private smile and a mild shrug. One day, she would like to make the big jumps of the Grand Prix.

But Pixie, who stands 14''1 hands (or 55 inches at the shoulder), won''t be the one to carry Alex over the Grand Prix gates. Those horses are eight, 10, even 12 inches taller than Pixie. Alex and Pixie regularly jump 3''3" fences, and once at a Christmas party competition at Pebble Beach they cleared a 4-footer to win the contest. But that''s a long way from the 5- and 6-foot gates of the sport''s crowning achievement. Even if, as Alex claims, Pixie can jump higher than 4 feet.

One of the many unfathomable things about Alex is how a light touch-light voice, light step, light hand-can leap past passivity and into the realm of mastery. Alex seems to be harboring a hidden vein of flint, because she and Pixie are very good at jumping. They are the two-time Grand Champions of the Pebble Beach Equestrian Classics Pony Jumpers division. Alex relays this information with about as much self-conscious pride-or self-conscious modesty, for that matter-as she would if she were reciting her family''s daily dinner routine.

"Every year I do pony jumpers, and every time I also win Grand Champion or Champion," she says. She adds that this week she is waiting on a phone call to find out if she and Pixie made the USA Equestrian Pony Jumper Finals in Lexington, Ky. If they did, they''ll be loading Pixie into a trailer or a plane the first week in August, just before Alex returns to school at Santa Catalina and her mother goes back to work teaching elementary school language arts in Salinas.

At the empty arena, Alex swings up into the saddle and starts off on Pixie. In the next paddock girls are gossiping about what someone they know did last night, or slowly cantering their horses through the deep talcum-soft dirt. From a distance they look poised on life-size rocking horses. The music-box melody of "Für Elise" plays over the tinny PA system.

Even after five years of riding, Alex is not allowed to jump without an instructor present. She walks Pixie, then nudges her into a trot. The mare''s short mane bounces with her gait, her head pops up and her ears swivel as if she is waiting for a command to do something more exciting. When she breaks into a canter her head comes back down and her neck arches in proper show horse form. It looks like Pixie is doing it of her own accord, but horses don''t do that naturally. Alex is making this happen, applying subtle pressure with her wrists and legs to make Pixie do her bidding.

Alex sits tall in her seat, talking to her mare, watching where she wants to go next, according to the dictates of the equestrian arts: chart your path with your eyes and your horse will follow it. As they round a corner of the arena I catch a startling glimpse of Alex. She is wearing a familiar expression on her small, childlike face: her features are still, and her gaze is locked on something just ahead, just beyond the visible, on the next few moments and the many years in the future. She is absolutely focused.