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Karissa Mechler sings only when she’s up in a tree more than four stories off the ground. She’s singing a lot these days.

Mechler is a fledgling professional arborist. And a rookie competitive tree climber, too. Last month, in her first-ever tournament, Mechler earned the right to represent the Mid-Atlantic region at the International Tree Climbing Championship, to be held in June in Nashville.

That’s a quick ascent for Mechler, 22. She got seriously into trees just last year, long after a cousin in the field began telling her how much she’d love his work. She didn’t believe him, for good reason.

“I’m afraid of heights,” says Mechler, a Wheaton resident. “When I was a kid, I climbed a red maple in my front yard all the time, but that was maybe 10 feet off the ground, not like the trees [the cousin] climbed for work. I figured this isn’t a job for somebody who’s afraid of heights.”

Yet Mechler finally succumbed to her kin’s lobbying effort and took a job with the Care of Trees, an Illinois-based consulting firm with offices in eight states. She now works out of the company’s, er, branch office in Annapolis. And, though she still goes wobbly whenever she’s way up in the air, she loves it.

Mechler spent her first several months on the ground, doing landlocked tasks to support co-workers up in the trees. But soon enough, she had climbed up the company’s ladder and into the trees and had learned how to use the ropes and saws well enough to complete tasks such as pruning dying branches—“widow makers,” in arborist parlance—and other deadwood from decades-old living skyscrapers. She found herself accomplishing these tasks at heights of up to 100 feet.

And, almost unconsciously, she found herself singing while doing them.

“I could handle anything up to 40 feet,” she says. “But anytime I had to climb higher than that, because of my fear of heights, I realized I would start singing nursery rhymes to myself. I guess I was trying to calm myself down. And it was working.”

Mechler realized that she wasn’t the only tree climber with worries.

“Everybody gets scared climbing trees,” she says. “That comes from knowing you can fall and you can die. I know that sounds kind of blunt, but that’s really what you’re thinking when you’re up in a tree 90 feet or even higher. That’s something everybody knows.”

Mechler says safety concerns probably have something to do with her falling head over heels in love with white-oak trees (“They’re big and strong and even the deadwood can hold you,” she says) and learning to detest poplars (“They’re tall and weak. I hate ’em”).

Given the results of a study by South Dakota State University using data collected from the U.S. Occupational Safety and Health Administration, tree climbers should be scared. The researchers found that arborist is the fifth-most-dangerous profession in the United States, with fatalities occurring at a rate of 41 per 100,000 workers, or more than 10 times the national average. (For comparison: The study found that police officers and firefighters lose 12 per 100,000 in their line of work.)

Hence the singing. Mechler’s go-to pacifier tune is “This Old Man,” the “knickknack paddywhack” song, which has lyrics that make no sense to anybody over the age of 5. Given her confessed phobia, her quick jump into competitive tree-climbing, just a year into the profession, seems equally nonsensical. She admits she didn’t have high hopes going into her debut competition, sponsored by the Mid-Atlantic Chapter of the International Society of Arboriculture and held April 9 at the University of Mary Washington in Fredericksburg, Va.

“I was going for fun,” she says. “I didn’t mean to win.”

As it worked out, Mechler’s path to the international championships wasn’t all that congested. Only one other female competitor entered the regional: Melissa Lawler, the 2004 champ. (The men’s field had 35 competitors.) The competition had five phases: the belayed speed climb, a timed event that has climbers following a rope in slalom fashion 60 feet up a tree; the footlock climb, another speed event, which has them climbing up 40 feet using a rope and branches but never touching the trunk; the throw line, a test of accuracy that involves throwing a weighted line at targets placed several stories up in a tree; the aerial rescue, getting to a dummy about 30 feet up in a tree; and the work climb, a simulated tree-trimming exercise in which climbers wear their full work outfits.

As game as Mechler was, through the early rounds of the event, Lawler appeared to be on her way to retaining her regional title. But in the work-climb portion, Lawler dropped a handsaw while up in the trees and was automatically disqualified. Mechler was the champ.

“I was trying my hardest, doing things I didn’t even know I was capable of doing,” she says. “On the work climb, I was swinging from branch to branch because that’s what you had to do, even though I’d never done that. I was so scared I wasn’t even singing! But the adrenaline rush of doing that, and having people cheer me on, was incredible. I loved it.”

The dearth of female tree climbers isn’t only a regional problem. Last year, only 12 women competed in the international finals, which were founded in 1976 and are now open to regional winners in preliminary events held in 20 countries. That was half the number of male entrants. But Sonia Abney of the International Society of Arboriculture, the Illinois-based group that sanctions the worldwide event, says the gender gap is shrinking.

“Our women’s competition only started in 2001, and we think that’s why the number [of female competitors] is still low,” says Abney. “Also, there weren’t that many women in the arboriculture industry, and that’s where most of the competitors come from. But as this becomes a less male-dominated industry and that number [of female arborists] increases—and our biggest area of growth now is with women—things will change for the competition. We’re going to see a lot more women in the trees.”

And so long as she keeps herself tethered, there’s no chance the competition will lose Mechler anytime soon. She says she’s been up in the trees practicing for the finals every day, on the job and off.

“I work all the time lately, and when I’m working I’m concentrating on improving the skills I’m going to need in the competition,” she says. “But the other day I had a day off, and I wanted some practice. So I asked my neighbor if I could prune her magnolia.”—Dave McKenna