0113.MysteryPlant

This Mystery Plant has fleshy pads that are actually modified stems and are often covered in glochids.

Here we go round the prickly pear

Prickly pear prickly pear

Here we go round the prickly pear

At five o’clock in the morning.

T. S. Eliot, “The Hollow Men,” 1925

Here’s a plant – yes, a cactus – that doesn’t seem to have many secrets. It is stark and obvious, all year long: massive, succulent pads foreboding plenty of spiny torment, with marvelous summer flowers and juicy reddish-purple fruits.

It is native from the American Southwest to about Mississippi, and grows now in cultivation just about throughout all the warm parts of the United States. It forms something of a shrub, although there really aren’t any true “leaves” to see. Fleshy pads are actually modified stems. The eye-like dots on the pads represent nodes, much like the eyes on an Irish potato. Yellowish spines (potentially dangerous) are sometimes present at the nodes. Otherwise, bundles of tiny, almost microscopic, modified plant hairs will be found in clusters at the nodes.

These tiny hairs, or “glochids,” are also potential problems: a cactus pad without spines should still be handled with great care (and sturdy gloves), as the glochids will dig themselves into your skin and can be very irritating.

This is just about the easiest plant there is to grow. All you need is one of the pads, buried partially into the ground. Give it a little while (and some water), and there you are. In really warm areas, the plants sometimes form a small tree featuring a distinct trunk. The plants seem to be able to tolerate winter temperatures into the 20s, but not below that.

All cacti are flowering plants, of course, and as such, produce flowers. The flowers of our Mystery Plant are extremely showy, bright yellow and feature plenty of petals as well as lots of stamens and pollen. The flowers are followed by massive egg-shaped green fruits (they are technically berries) which generally turn red or purple, and which have historically been called “tunas.” (Some cultivated versions have yellow fruits.) These berries are filled with deep-red pulp, and a considerable number of seeds. The juice is highly prized as a healthful beverage. Of course, if you are going to try juicing the berries at home, be prepared for some work. (And, remember the glochids, which are also on the fruits.)

A different species in this genus, one that cannot withstand freezing, is the one featured as a food source in many parts of Latin America, and is commonly seen in well-stocked mercados, sometimes with the glochids burned away with a blow-torch. Generally, these pads (“nopales” in Spanish) may be skinned, and then sliced and sautéed. There are plenty of recipes for both fruits and pads. Delicious. Native “prickly pear” cacti occur in just about every one of the continental United States. (Photo by John Nelson.)

[Answer: “Engelmann’s prickly-pear," Opuntia engelmanii]

John Nelson is the curator of the A.C. Moore Herbarium at the University of South Carolina, in the Department of Biological Sciences, Columbia. As a public service, the Herbarium offers free plant identifications. For more information, visit herbarium.org or call 803-777-8196, or email nelson@sc.edu.