TERREBONNE — An Appaloosa gelding named Joker took 2 minutes and 20 seconds earlier this month to find a carefully hidden volunteer in a 13-acre, semi-wooded field near Terrebonne.

Jefferson County Sheriff Jim Adkins watched, astonished, as Joker and rider George Ehmer, 66, of Milton-Freewater, nosed out the hidden volunteer.

It was a dramatic and spectacular demonstration of what practioners call “equine air-scenting.” The event was organized by a loosely knit Central Oregon group that hopes to use horses in the role of bloodhounds during backcountry searches.

“They’ve definitely got my attention,” Adkins said. “That was a pretty difficult search because the wind kept changing on us. That horse just went right over there and zigged and zagged and zoomed right in.”

Horsewoman Kate Beardsley, of Redmond, arranged the search demonstration with Laurie Adams of Camp Sherman. They are assembling a team of a dozen air-scent trained horses and riders that they hope eventually will be deployed around the Northwest when hunters, hikers and others go missing.

“A lot of people don’t know that horses do this at all,” said Beardsley. “Laurie and I are focused on saving lives.”

The ranch-raised Beardsley, 47, said a horse’s olfactory receptors rival those of a tracking dog. As a horse trainer, professional horse packer and founder of a nonprofit horse rescue called Mustangs to the Rescue, Beardsley owns two horses schooled in air-scent techniques and has helped organize air-scent clinics here for six years.

While little-known, the concept has been around awhile.

“I call it the lost art,” says horse trainer Terry Nowacki of Argyle, Minn., who began reviving the techniques about 11 years ago. “It is the best-kept secret in the horse world.”

Theodore Roosevelt was aware of what horses’ noses can do, and hired a hunting guide in the 1880s that “followed his horse’s nose to buffalo,” according to Roosevelt biographer Edmund Morris.

Four decades earlier, a mustang called Sacramento repeatedly saved explorer Col. John Fremont’s life by scenting enemies along the trail, wrote frontier historian Glenn Vernam. Texas folklorist J. Frank Dobie also wrote of horses with exceptional noses in his 1952 book, “The Mustangs.”

Tracking dogs can outperform horses in thick underbrush, said Nowacki, 57. But horses often hold the advantage because airborne scent rises, and horses stand taller than dogs, he said.

Nowacki has written two books, the “Air Scenting Horse,” and, “Equine Language and Communication Journal.” Nowacki has a website, Equine Detection Services, and hosts four or five clinics a year on equine air-scenting around the nation, including one in Terrebonne in early June.

“This is so natural for a horse,” Beardsley said. “Horses smell everything, and they tell everyone around them what they smell.”