Happy Trails for 2 : John and Julie Gensley have led nature walks through the Santa Monica Mountains for decades.

John and Julie Gensley are showing a visitor around their ruggedly beautiful 35-acre Santa Monica Mountains ranch. They point out the old outhouse, a defunct water well and the active beehives.

“You didn’t see me, but I was saying hello to all my old friends,” Julie says with a chuckle, referring to the native plants that abound on the land the Gensleys have owned for 52 years. The two nature walk docents, who conduct tours at Soka University, have been teaching Santa Monica Mountains lore to visitors since before there were state parks in the area.

“We’re old fogies,” says John, 86, with a laugh.

He points to the top of the mountain ridge and recalls the day last year when what he called “a canopy of flames” came over the crest and roared down toward the house. Julie, 84, went ahead with a planned trip, figuring John knew what he was doing. After all, firefighters had made the Gensleys’ something of a command post.

“I had the sprinklers going,” John recalls, “and I thought I had the place pretty well cleared, and I thought, now here I am all alone. What do I do next?” Luckily, two firetrucks pulled up, right on cue.

After the flames were out--the fire stopped inches from the patio--there was “a shower of sparks, just like a Fourth of July firecracker up there--beautiful,” John remembers, still awe-struck.

“The fire came to (within) one foot of their house,” marvels Earlyn Mosher, manager of community relations for Soka University. “To me, that was like, nature respects them. Nature protected them because that’s what they do for nature.”

The Gensleys helped establish the nature walk program in 1990 at Soka University, which recently dedicated its new demonstration garden to them. Officially, it’s the John and Juliana Gensley Botanical Research Garden.

“All I can say is, as human beings I respect them so much because they’re so young. They’re aged, but they’re younger than most people. I want to be like them when I grow up,” Mosher, who is 45, says with a laugh.

John and Julie grew up not far from each other in a then-ritzy Los Angeles neighborhood near MacArthur Park. They met in 1931 at a horseback riding party. “The horses that were assigned to us spent the whole evening together. They liked each other,” recalls Julie. The couple married the following year.

“We lived simple and saved our money, because we knew we wanted to buy a place that was far enough out that it would be wild and beautiful, and near enough in that we could get there every weekend and not have to wait until vacations,” Julie says. Before buying their mountain home, the couple lived in Hermosa Beach. Julie was a professor of education at Cal State Long Beach; John had a career in banking.

In the early years, John and Julie would bring their young son and daughter up on weekends to sleep in sleeping bags on the land while their house was being built. Their involvement with various community groups led them to invite visitors to the ranch; these rambles turned into the area’s first nature walks.

“There were no state parks at the time in the area, and we were practically the only resource that was available,” Julie says.

Their knowledge of the local flora and fauna became well-known--Julie was called “the oak tree lady” because of her expertise--and she and John were among the earliest docents at Topanga State Park and later Malibu Creek State Park, where Julie still volunteers.

Julie says she’s mostly self-taught. “You pick it up a day at a time, and when you’ve lived as many days as I have, it’s a lot,” she says with a laugh. But she also remembers her father taking her on walks and pointing out plants and flowers when she was a toddler. Her knowledge rubbed off on John.

They helped form Friends of Soka University in 1986, after being impressed with how the Soka administration cleaned up the property and seemed to respect its natural beauty. Julie suggested the nature walk program as a way to publicize the university and give it some good public relations. (The Japanese language school, which had hoped to expand, is trying to fend off a bid by the Santa Monica Mountains Conservancy to condemn much of the land for use as a park visitors center.)

Soka created the demonstration garden at Julie’s request. On a recent visit, Julie walked a visitor around and showed how the garden answers the question she is most often asked on nature walks: “What’s the best time to see wildflowers in the Santa Monica Mountains?”

“In the Santa Monica Mountains, there are wildflowers blooming every day of the year,” she says proudly. The garden demonstrates just that. It also provides a sort of outdoor-classroom starting point for the nature walk, which takes visitors to the top of a steep hill and back.

“Some people say, ‘I just can’t hike that far,’ ” says Julie, who still does the climb regularly. In the garden “you get an overview.”

Julie points out interesting tidbits--mugwort grows near poison oak, and its leaves contain an antidote to its poisonous neighbor; hummingbirds are native only to North and South America; you can always tell a sage by its square stem.

“People say, ‘How can you remember all these things?’ ” Julie says. “My earliest memories are of flowers. I remember bringing flowers to my grandmother when I was 2. First thing, when I’m in a new environment, I look for the flowers. My husband’s that way with cars. We’ll be driving along, and he’ll say, ‘Look, look!’ And I’ll say, ‘Oh, crape myrtle!’ And he says, ‘No, I meant that BMW.’ ”

Though Julie says John is planning to scale back his nature walk duties in favor of less strenuous volunteer work, she has no plans to retire.

“I don’t even look into the future that far,” she says. “If I’ve got an opportunity today, that’s terrific.”