Stretching toward a subdued autumn sun, an army of saguaro cacti wave at me with their massive prickly arms. Their eerily human-shaped shadows blot patches of the rocky trail as hues of orange, crimson, purple and blue paint a psychedelic sunset across the western half of Saguaro National Park, the most diverse desert ecosystem in the world.
It's an ecosystem at risk: Ecologists fear an invasive, fire-resistant Ethiopian grass introduced to the area in the 1930s as cattle fodder could transform the desert into a barren grassland.
Now, though, the landscape is astonishingly green. Where I naively imagined swaths of Saharan-like sand dunes, tufts of palo verde trees share the parched soil with mesquite trees,
the ubiquitous prickly pear cacti (whose fruits make a mean margarita), and short, fuzzy-looking teddy-bear cholla and jumping cholla cacti.
"You don't want to hug one of those," jokes Lynne Rigoletti, an encyclopedic docent at the Arizona-Sonora Desert Museum, an outdoor zoo and botanical garden. "Their spines will stick to your skin even if you barely brush past them. And they're barbed, so they're extremely hard to remove."
I trek through the Desert Museum in search of hummingbirds, reptilian Gila monsters, pumas, roadrunners and any of the other 300 animal species surviving in this almost alien landscape.
More than 1,200 different kinds of plants sprout on the hillside, each with exotic monikers that make me want to name them out loud, slowly, like an angry rattlesnake. Su-ccu-lentssssssss, I say to myself, admiring an aloe vera plant.
It's a veritable cornucopia that quickly has me regretting my short stay. There are more than 264 kilometres of trails winding through Saguaro National Park's eastern and western halves, crossing various ecosystems ranging from desert scrubland to grasslands to pine and oak woodland forests. "The scenery is quite different from anywhere else in the U.S.," says former Tucson local Jim Roth, who has dedicated a whole website to the park and its trails (www.saguaronationalpark.com). "And there are these very rugged mountains that make it a really spectacular place."
He should know. At 46 years old, he has already hiked 28 of the country's 58 National Parks. For hardy hikers who want a challenge, Roth recommends the Tanque Verde Ridge Trail in Saguaro Park East, which reaches heights of 8,000 feet and connects to various backcountry campgrounds. "It's basically climbing up a ridge and the views are just spectacular," he says, suggesting a three-hour hike to the 4,000-metre level for a day trip. "You can see three mountain ranges: the Tucson Mountains to the west, Mount Lemmon to the north and the Santa Ritas, which are way down south."
But families or those with less endurance can reach some of the desert's most mysterious sights. An easy two-kilometre jaunt to the peak of Signal Hill reveals a treasure trove of boulders scarred with dozens of perplexing petroglyphs left behind by a lost civilization, the Hohokam peoples, who date back to the beginning of the last millennium. Horned antelope-like creatures, geometric shapes resembling flowers and a giant swirl are scratched out on blackened rocks overlooking a 360-degree view of the desert. "That's where I usually take my family," Roth says. "I definitely recommend it to anyone who only has a day."
But if you're anything like me and your belly dictates your travels, you'll take a break from the trails to savour the desert's unexpected culinary offerings. The Desert Rain Café, run by members of the Tohono O'odham Nation, serves a surprising variety of local, seasonal desert dishes, such as prickly pear grilled pork ribs or cholla bud, jicama and citrus salad. Its delicious, affordable meals have been motivating locals to make the one-hour drive west of Tucson since it opened last year. And since the Tohono O'odham believe themselves to be descendants of the Hohokam peoples, it's also the perfect place to debate what Signal Hill's perplexing prehistoric petroglyphs really mean.
Whichever corner of the desert grabs you, now might be a good time to see it. Only a quarter-century since the U.S. Congress created Saguaro National Park, ecologists, parks workers and volunteer wildlife enthusiasts are worried: Buffelgrass, the invasive Ethiopian grass, is spreading at an alarming rate. Some are predicting that if it continues at its current pace, buffelgrass could swallow 60 per cent of the park by 2018, threatening to transform this diverse desert into the barren African grassland from where it came.
"Buffelgrass is the scourge of the desert at this point,"
Rigoletti says about the innocuous-looking blond weed. "We're really quite worried about it."
Buffelgrass doesn't just grow like wildfire - its Ethiopian roots make it immune to the heat. The weed grows back denser than ever after a fire and has the potential to burn easily, fast and at extremely high temperatures. One lightning strike, a misplaced cigarette butt or a house fire at one of the elegant high-end homes overlooking the desert from the outer edges of Tucson could set acres of bufflegrass alight, along with all the wildlife it knits together. If such a scenario occurred, it would take decades for mere inches of the park's namesake saguaros to reappear, if any of their seeds survived.
Some locals are so concerned that they don't even allow themselves the luxury of sleeping in. There are at least seven groups of weed whackers, an average of 100 individuals each month, who get up at the break of dawn several times a week to feel the satisfying shred of buffelgrass being pulled out of the desert floor.
One group, the Sonoran Desert Weedwackers of Tucson Mountain Park, led by retired biology teacher Marilyn Hanson, has strenuously hand-pulled an estimated 120 tonnes of the weed since the group's inception in 2000. "We have an incredible energy in this city," Hanson says about Tucson. "We're a community determined to fight back invasive plants that have the potential to destroy the very environment that drew us here."
The wildflowers and native grasses that garland the land once hoarded by buffelgrass show the Weedwackers' efforts are working, but the volunteers simply can't keep up. Already, the weed swarms an estimated 2,000 acres of Saguaro National Park.
But for now, at least, buffelgrass hasn't ruined the park's quiet, stoic charm. Trying not to dwell on the six species of rattlesnakes I imagine slithering somewhere between the cracks, I walk through an army of saguaro and stare at the Tucson Mountains turning shades of purple in the twilight before heading back to town. I picture the lynx lurking on those peaks, the roadrunners dodging wily coyotes and the variety of scaly creatures coming alive in the cool evening air.
An especially tall saguaro heavy with limbs commands the horizon and I try to envision the brief evening this June when it will release its large white flowers, which bloom for only 12 to 18 hours, once a year. I've heard various people describe the blossom's peculiar smell as intermittently sweet, musky, or like an overripe melon, but Rigoletti from the Desert Museum doesn't beat around the bush. "They smell terrible," she says. "But only those that are pollinated will make a fruit," she adds with a smile, "and those are delicious."
Arizona's striking Sonoran Desert Five Ways
The Arizona-Sonora Desert Museum features all the prickly giants and creatures surviving in the Sonoran Desert. Among them: pumas, coyotes, roadrunners, desert tortoises and javelinas. The drive there is spectacular. www.desertmuseum.org
Locals are braving the two-hour drive west of Tucson to feast at The Desert Rain Café - located way off the beaten track in the small town of Sells, on the Tohono O'odham Indian Reservation - for traditional, local, healthy and seasonal desert fare. Think prickly pear chicken sandwiches, O'odham squash enchiladas or tepary bean and short-rib stew. Nothing costs more than $8 (U.S.) a plate. www.desertraincafe.com
If you're one of the few braving the desert sun in June, don't miss out on the annual Saguaro Harvest at the Arizona-Sonora Desert Museum or at Colossal Cave Mountain Park. Only members of the Tohono O'odham Nation are allowed to pick the fruits of the saguaro, but once a year they share the tradition with visitors and teach them how to make their prized sweet saguaro syrup. www.colossalcave.com
Saguaro National Park east and west both have dozens of free events every week year-round. Intrepid hikers can hit the hills themselves or join park rangers for guided sunset hikes, star-gazing parties or lectures ranging in topics from the Hohokam peoples to saguaros to snakes. www.nps.gov/sagu/index.htm
Volunteer for the Saguaro Census this month, which takes place once a decade. Discover remote patches of Tuscon's desert as you take stock of the health of its statuesque icons. www.nps.gov/sagu/naturescience/saguaro-census-2010.htm
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