What it means
The barrel cactus is the one shaped like its name: a thick, ribbed green keg bristling with spines, usually knee to chest high, with a ring of flowers or a crown of yellow fruit on top. Locals call it the compass cactus because grown plants lean, sometimes dramatically, toward the south. Visitors call it “the fat one,” and the desert plants field guide lists it in the supporting cast for exactly that reason: it is everywhere, it is easy to recognize, and it has one good story attached that happens to be false.
Around Scottsdale there are really two. The fishhook barrel, Ferocactus wislizeni, is the landscaper’s barrel, planted in medians, resort entries and front yards, with a stout hooked central spine that gives it the name. The California barrel, Ferocactus cylindraceus, with long, curving, reddish spines, is the one the McDowell Sonoran Conservancy’s volunteers documented on the slopes of the Preserve. Both lean, both bloom on top, and both are what people mean by “barrel.”
You will hear the word from a nursery worker (“keep the S facing south”) and from every hiker who has ever pointed at one and said, “So that’s north.”
Where you’ll meet it
Labeled specimens stand at the Xeriscape Garden at Chaparral Park; wild California barrels dot the rocky slopes of the Preserve and Pinnacle Peak; fishhooks fill the gravel yards of half the subdivisions in town. Look for orange and red blooms from late summer into fall and yellow fruit through winter.
Where the word came from
“Barrel” is plain English description, and nobody has claimed it. The Spanish name is older and more useful: biznaga, the word still printed in Arizona’s protected-plant rules, and the Arizona-Sonora Desert Museum’s nursery sheet calls the fishhook biznaga de agua, the “water barrel,” a name that preserves the myth inside the plant’s own label. The fishhook was also known as the candy barrel, after the old practice of making candy from it. Ferocactus is botanical Latin for “fierce cactus,” which is fair.
The compass nickname comes from behavior, not folklore. The Park Service’s explanation is simple: the side of the plant in shade grows faster than the side baking in the southern sun, so over decades the cactus tips south. Old barrels can lean so far that, after a heavy rain loosens the soil, they pull up their own shallow roots and fall over. A barrel lives 50 to 100 years, so a toppled one in a wash has usually been leaning since before the subdivision next to it.
The water story is the one everybody repeats. Lost prospectors in Western novels slice the top off a barrel and drink. Real barrels hold a slimy, alkaline juice heavy in oxalic acid, and drinking it causes cramping, vomiting and diarrhea. The O’odham and other desert peoples had better uses: the Park Service records barrels hollowed out as storage containers and cooking vessels, spines used as awls and tattoo needles, and the fruit eaten.
What it is not
Not a golden barrel, the round, bright-yellow-spined Mexican species planted in rows at shopping centers; it is a landscape import. Not a hedgehog or pincushion, which are much smaller. And not a water source, ever.
The fine print
The fishhook barrel usually stands two to six feet, occasionally ten, about two feet wide, with 15 to 28 ribs. Its pleats work like the saguaro’s, expanding to store water after a storm, and the Park Service notes that a barrel that takes on too much water can split its skin, opening the way for bacterial rot.
Bloom timing is a reliable field mark. The fishhook flowers in the heat: the Desert Museum puts the start in July or August with blooms lasting up to eight weeks, mostly orange, sometimes yellow or red, pollinated mainly by bees. The fruit ripens in late fall and winter, has an edible rind with a lemony taste, and can hang on for more than a year until birds, squirrels, deer or javelina take it.
The law covers both species. Arizona’s protected native plant rules place every Ferocactus in the salvage restricted category, alongside the saguaro, cholla, most prickly pear and the ocotillo, which means removing, transporting or selling one requires landowner permission and a Department of Agriculture permit and tag. Builders salvage barrels before grading a lot, and nurseries sell them tagged.
If you plant one, the Desert Museum’s advice is to keep the nursery orientation, marked with an S on many pots, and acclimate it gradually; a barrel turned to face a new direction can sunburn on the side that used to be in shade. The first-year guide has more on what survives a Scottsdale yard.