It’s a big desert out there, with what seems like plenty of room for cacti to spread out across the landscape.
But if you wander the desert near Tucson on foot — from Sabino Canyon to Saguaro National Park and other sites — you might notice quite a few of what we might call “cactus clusters.”
We’re talking about cacti, usually three or more saguaros, that are growing very close together — sometimes touching one another with no space between them.
“It’s so impressive when you stumble across these clusters,” said Don Swann, biologist with Saguaro National Park. “They stand out in the desert and cause you to stop and take pause.
“They’re nestled together as if in friendship,” Swann said.
The precise causes of the tightly grouped cacti aren’t certain, but Swann and other biologists have some theories.
“In my experience, when I see these clusters, if I look around there will be the remains of an old ‘nurse tree’” — a palo verde or mesquite tree that provided shelter for very young cacti, Swann said. “They grew up under the protection of that tree. The seeds of the saguaros apparently fell pretty close to each other and conditions were favorable for their survival.”
Other cactus experts have suggested that soil and weather conditions might be factors in producing cactus clusters.
WHERE TO SEE CACTUS CLUSTERS
Clumps of saguaros — and sometimes other types of cacti — grow very close together in many expanses of desert around Tucson.
Several trails in Sabino Canyon northeast of Tucson pass cactus clusters. Among them is the first half-mile of the Esperero Trail, which begins near the visitor center at 5700 N. Sabino Canyon Road.
At Saguaro National Park east of Tucson, clusters show up in various parts of the cactus forest district, Swann said. A section of the park’s Cactus Forest Trail has several clusters. It begins at the Broadway Trailhead near the eastern dead-end of Broadway.
A close-together clump of saguaros. — Credit: Doug Kreutz/Arizona Daily Star
Cactus clusters can be found on several trails in Sabino Canyon, as well as at Saguaro National Park east of Tucson.
Saguaros standing side by side. — Credit: Doug Kreutz/Arizona Daily Star
Even with lots of open space, some saguaros choose togetherness. — Credit: Doug Kreutz/Arizona Daily Star
Unusual clouds grace the sky over a cluster of small saguaros in Tucson Mountain Park west of the city.
