A routine hike outside Scottsdale turned serious on October 17 when strong winds toppled a saguaro cactus onto a hiker's head, knocking her unconscious on the Bell Pass Trail. The roughly 6.6-mile out-and-back route winds through the McDowell Sonoran Preserve, and the Scottsdale Fire Department's technical rescue team had to hike about two miles up the trail to reach her.

A witness on the trail told The Arizona Republic that the fallen cactus left the hiker unconscious for five to ten minutes, with injuries from both the plant's weight and its spines. Her companion managed to lever the several-hundred-pound section off her using a strap, but the woman showed signs of head trauma — she couldn't recall the year or who the president was. Rescuers carried her out on a litter, transferred her to a UTV, and took her to a local trauma center.

It sounds freakish, but saguaros are genuinely heavy hazards. They're the largest cactus in the United States — recorded specimens top 78 feet and 10 tons — and the preserve is full of them. There's even a fatal precedent: in 1982, an Arizona man shooting at a 23-foot saguaro with a shotgun was crushed when one of its arms collapsed on him. He remains the only person on record killed by a cactus in America.

Far more common are the small, annoying encounters. Cholla cacti, common across the Southwest, have barbed spines that grip so well that a 2018 study in Proceedings of the Royal Society B found a single spine could lift half a pound of pork shoulder. Most run-ins, though, are manageable with a basic first aid kit. Wilderness medicine expert Buck Tilton recommends plucking spines out one by one with tweezers, or — the clever trick — packing white glue or rubber cement for cactus country hikes. Spread glue over the embedded spines, press gauze on top, let it dry, then peel: the spines come out with the gauze.

Why should holidaymakers care? Arizona's desert trails are a huge draw in the cooler months, and saguaro country is one of the most distinctive hiking environments on earth. Incidents like this are rare, but they're a reminder to check wind forecasts before heading into the preserve, keep a companion within reach on exposed trails, and toss a small glue tube and tweezers into your daypack. Five minutes of kit prep beats a litter evacuation.