The safety of the student climbers and the protection of trees are top concerns for Tim Kovar.

"O nce you get five feet up, be sure to check those safety knots," instructor Tim Kovar told the half-dozen members of his tree climbing class Tuesday as they began inching their way up ropes draped over the limbs of a towering black walnut tree in North Mountain Park.

That morning, the students had memorized how to tie the variety of knots they would need to climb safely into the tree, hang in the air to admire the view and then work their way back down.

Afternoon marked the true test of whether they had paid sufficient attention to the critical lessons.

With all six of his students safely up in the air, Kovar called out, "Congratulations! You're hanging on your own knots."

A teacher with Portland-based Treeclimbing Northwest, Kovar had traveled to Ashland for the class, which was offered through the Ashland Parks and Recreation Department.

The safety of the student climbers and the protection of trees are top concerns for Kovar.

"These are our hosts holding our lives up there," he said.

He noted that the ropes that passed over the walnut tree's limbs went through protective tubing that protects the bark from being rubbed raw by friction from the ropes. Climbers chose live limbs at least six inches in diameter for their ropes.

To get a white climbing rope draped over a tree limb in the first place, Kovar threw a thin, orange cord-like rope that was weighted with a beanbag over a limb.

The orange line could then be used to pull up the climbing rope.

Rather than scrambling up the trunk of the walnut tree and onto its limbs, the student climbers — each on a climbing rope — sat in harnesses that encircled their waists and upper thighs. They pushed against rope stirrups with their feet while pulling on the climbing rope with their hands. Using the technique allowed them to put their powerful leg muscles to use, rather than relying on upper body strength alone.

Somehow, through an almost magical combination of the right knots and their climbing gear, the climbers were able to hoist themselves upward while dangling in mid-air.

Kovar said he once trained two 75-year-old women to hoist themselves into trees on ropes.

"They said they hadn't climbed in 65 years," he said.

Years ago, Kovar worked as an arborist, cutting down hazardous trees. That changed when he was bringing down a tree and hit a water pocket hidden inside the wood. As the water gushed out, Kovar said he could swear that he heard a sound as if the tree were screaming.

He switched to teaching people how to climb trees as a form of recreation.

"Tree climbing helps open people's minds to the natural environment," Kovar said.

As the afternoon wind blew through the walnut tree's verdant leaves and gently buffeted the student climbers, Kovar talked to them about his climbs around the world.

"In the Amazon, you get the parrots coming through and the macaws. It's a beautiful place to do it," he said.

Once 14-year-old Nalani Thiel was hanging just below the limb that supported her rope, Kovar encouraged her to kick her legs up and suspend herself upside down.

"Now go ahead and let go with your hands and reach for the ground," he called to her.

With a nervous laugh, Thiel turned upside down, 25 feet above the ground.

Later, when she had her feet planted again on the park's lawn, Thiel said she felt fairly confident about the move after the day's training. "I knew I wasn't going to fall. I am a little afraid of heights, but it was fun," Thiel said.

After he was back down on the ground, Donald Johnson, 56, said he plans to apply what he learned in his own backyard, where he has some oaks that need pruning.

He said hanging with ropes and a harness from a tree actually felt safer than being up on a ladder.

"Tim did a great job telling us how to tie the knots. We did it over and over," Johnson said. "In fact, we did it with our eyes shut."

Staff writer Vickie Aldous can be reached at 541-479-8199 or vlaldous@yahoo.com.