What it means
Prickly pear is the flat cactus: a shrubby clump of oval green pads stacked edge to edge, each pad studded with clusters of long white spines and, at the base of each cluster, a tuft of near-invisible hairs called glochids. Locals use three words for it depending on what they are doing. Prickly pear is the plant on the trail. Nopal is the pad in the kitchen, scraped and diced into nopales. Tuna is the fruit, the egg-shaped knob that ripens from green to deep magenta along the top of each pad in late summer and ends up, by way of a syrup, in the pink drink the happy hour guide warns you about.
That drink is the reason most visitors learn the word. The prickly pear margarita has its own entry; so does the glochid-adjacent cholla, which the desert plants field guide ranks as the plant that ruins more afternoons than anything with a pulse. Prickly pear is less aggressive. It waits for you to touch it.
Where you’ll meet it
On every slope in the Preserve, in the median plantings along Scottsdale Road, labeled at the Xeriscape Garden, on the menu as syrup, jelly, candy and cocktail, and in September, when the fruit is ripe and the javelina come down for it.
Where the word came from
The English name is a description from the colonial Caribbean, where the fruit’s shape and spines earned it “prickly pear” by the 1600s. The Spanish words are more precise. Nopal comes from the Nahuatl nohpalli, the Aztec name for the plant; tuna came from the Taíno of the Caribbean for the fruit, and has nothing to do with the fish. Arizona kitchens use both without translation.
The cactus itself is Opuntia, a huge genus, and the common native of the Scottsdale desert is Engelmann’s prickly pear, Opuntia engelmannii, named for George Engelmann, the St. Louis physician and botanist who described many Southwestern cacti in the nineteenth century. It grows in clumps three to five feet tall and up to fifteen across, on south- and west-facing ground and sandy soils, with gray-white spines up to three inches long. The flowers open yellow, occasionally reddish, in April and May, each lasting a day or two, and the fruit sets by midsummer and ripens purple from late July into September. Every tuna holds 144 to 172 seeds, which is why coyote scat on the trail in September looks like birdseed.
People ate it long before anyone bottled it. The Tohono O’odham harvested tunas as a summer staple, and across Mexico the cultivated nopal became a vegetable crop and, with the cochineal insect that feeds on it, the source of the red dye that colored European cardinals and British redcoats. The fruit is high in vitamin C and potassium; the pads carry iron and vitamin A. Prickly pear jelly, candy and syrup came north with Mexican cooks and became Arizona gift-shop staples, and the margarita followed in the resort era.
What it is not
Not a cholla, which is a cactus of cylindrical, detachable joints rather than flat pads, and whose spines travel with you. Not a barrel cactus, which is one fat column. And the smooth, tender nopales in a Mexican market are usually a cultivated, nearly spineless species, not the Engelmann’s in the wash.
The fine print
The glochids are the whole safety briefing. The long spines are visible and you avoid them; the glochids are barbed hairs a few millimeters long, growing in dense tufts, that detach at a touch and lodge in skin, where they itch for days. The University of Arizona’s extension notes they were once used to make itching powder, which tells you everything. Handle pads and fruit with tongs and leather gloves. For fruit, pass each tuna over a gas flame until the glochids flare and vanish, then slice and scoop or boil and strain through cheesecloth for juice. For nopales, scrape the glochid nodes off under running water, peel, trim the edges, dice, and parboil five to ten minutes to cut the slime. Nevada’s extension adds a rule people forget: do not rinse a glochid-stuck hand under the tap first, which only drives them in; press tape or dried glue over the spot and peel.
Fruit does not ripen after picking, so wait for full color; ripe tunas twist off clean. Harvest from plants off the road, where exhaust and herbicide have not settled, and leave plenty, because javelina, coyotes, birds and tortoises are eating the same crop. Pads can be taken in spring when young and still dark green.
In the yard the plant is nearly indestructible. A single pad laid on gravel roots into a new clump, and its only enemies are scale, mealybugs and the white, cottony fuzz of cochineal insects, which rub off red and wash away. Dogs are not poisoned by it, though one that noses a pad comes home with a muzzle full of glochids and an opinion. The syrup freezes well, keeps for months, and makes the bar version of the drink look overpriced.