What’s Killing Joshua Tree National Park?

Photos by Debra DiPaolo (left) and Sara Munro

It was, we all agreed, a beautiful fire. Five years ago, during the last week of May, a few friends and I hiked into Joshua Tree National Park just after sunset, intending to spend most of the night exploring its washes and climbing its soft granite boulders under a bright full moon. We convened at the Beatnik Café in downtown Joshua Tree, then a rundown serve-yourself coffee shop that offered magazine-strewn black tables and the rare twin luxuries of an Internet connection and espresso. From there, we drove to the Quail Springs Road backcountry trailhead, made camp at a flattish cluster of rocks three miles from the road and then set out to enjoy the night.

We were reckless, but not alarmingly so. Two of our six slipped after they trusted their hands to unstable rocks; I fell butt first on a cholla cactus. But the full-moon expedition — the first of many on different trails in other wilderness areas — would remain forever memorable, not simply for its thrills but for a scene we interpreted as exquisite: Just inside the park’s West Entrance, to the west of Quail Springs Road, a fire simmered on the rocky hillside, turning the moon blood-orange and filling the skies with spectacular light.

We didn’t lament that fire; we thought we knew enough about environmental cycles to assure ourselves that fire is a necessary event in the wildest places: In many northern and mountain woods, for instance, pines can’t germinate unless their cones explode, which only happens at the kinds of high temperatures that occur in a fire. Later we’d find out that lightning caused the blaze, which comforted us all the more — this wasn’t arson at work, but nature. But all our previous Outward Bound sojourns and minimum-impact backpacking seminars had taught us not a thing about the strange ecosystem of the desert, or about how succulents were not meant to burn.

In the morning, after watching the sun push through the smoky sky to a near-psychedelic dawn, we were greeted at the trailhead by a ranger, who had spotted our cars. The fire had jumped the road, and the park had been evacuated the night before. “Who let you in?” the ranger wanted to know. We looked at him quizzically: The park entrance had been open and unmanned the night before, as it always is after business hours. A better question might have been: Why wasn’t there anyone around to stop us?

Last January, I returned to the scene of the Juniper Complex Fire, as the 1999 fire was named, in the company of Howard Gross, the California Desert Field Representative for the National Parks Conservation Association (NPCA). I was shocked at what I saw. A pine forest by now would have turned green and purple with lodgepole pine seedlings pushing through opportunistic fireweed; it might look more like a bucolic meadow than a fire-ravaged forest. But this was barren ground, with only charred stumps of black brush and cat’s claw left to punctuate the sandy desert floor.

Earlier in the day, Gross, a tall, slow-talking man not given to hyperbole, held a press conference for a tiny gathering of journalists to announce that Joshua Tree National Park had been listed for the second consecutive year as one of the 10 most endangered national parks in the U.S. Most of Gross’ evidence turned out to be at the burn site: acres and acres of nothing.

“We think we’ve lost 40 percent of the black brush in the last 30 years,” Gross said as he kicked a blackened stub, “and about a fifth of the Joshua trees,” all of it to fire — fires that should have ignited only a small area and died fast for lack of fuel.

What caused the fires to be so destructive? Los Angeles smog, for one thing. Arriving at that conclusion, however, requires a substantial detour through desert ecology, a minor chemistry lesson and a mind-bending understanding of the interconnectedness of everything in nature.

The problem begins with nitrogen, which along with sulfur dioxide and ground-level ozone, is one of the components of air pollution produced by internal-combustion engines in the form of nitric oxide (NO) and the greenhouse gas nitrous oxide (NO2). Having blown in through the mountains, NO and NO2 bind to airborne dust particles and settle on the naturally nitrogen-poor desert floor.

“It’s called ‘fertilizing the desert,’” says Gross. Plants that belong in the desert don’t need nitrogen, but non-native grasses, such as red brome and cheatgrass, thrive like backyard tomato plants on it, even in the absence of water. The grass grows tall and spreads in the winter, dries out in the spring, and efficiently conducts fire from plant to plant in the summer and fall.

Nearly three-fourths of desert fires are caused by lightning, and there was a time when they did little damage: Desert plants normally grow far enough from one another that fire doesn’t spread fast among them. Had the desert been in the same condition it was 50 years ago, the 1999 lightning strike should have left behind nothing more than a small scorched patch. Instead, its spark caught a field full of tinder-dry grass parched from a hot spring and a yearlong drought, and the flame tore through the desert with unprecedented speed, destroying nearly 14,000 acres in just under three days. The Juniper Complex fire was the worst fire in Joshua Tree’s recorded history, which dates back to 1945.