For most people living outside the US, and for many inside the US, the word “cactus” brings up two images. The obvious first one is of a saguaro (Carnegiea gigantea), even though the saguaro is (a) one of the most extreme in size of all cacti, and (b) restricted to only a small area of southwest North America. (I’m still amazed at how often saguaro imagery shows up in cowboy motifs in Texas, even though the nearest one in the wild is in Arizona. It’s that iconic.) The second is of some sort of prickly pear (Opuntia spp.), which is a little more reasonable. Prickly pear not only thrives in desert and semi-desert, but just about any place with sufficient drainage for its roots and protection from long freezes. In fact, most people are surprised to find them thriving in the mangrove swamps of the Ten Thousand Islands in Florida.
Once those cliches are out of the way, Texas cacti have a lot of charms on their own. The best cactus-viewing in the state can be done around Big Bend National Park, and I heartily recommend such trips in mid-March, when the cacti and associated succulents are in full bloom. In the Dallas area, most cacti are limited to collections and the occasional prickly pear in an especially viable area (the seeds are spread by birds, so lone prickly pears can be found hundreds of miles away from their nearest neighbors), but go a little west of Fort Worth, and both cacti and agaves become significant components of the local flora.
Out on the west side of the Brazos River, for instance, it behooves visitors to be careful underneath scrub trees such as mesquite. This is preferred habitat for Opuntia leptocaulis, locally known as “pencil cactus,” among the names that can be printed. The Czarina’s family refers to it as “break-stick cactus,” from its habit to break off in chunks on skin, hair, and clothing, and it can be a menace in places where it grows alongside roads, trails, and paths.
As can be told from its habits, O. leptocaulis isn’t especially fussy about its soil requirements, but it needs shade when smaller. Like all flowering plants, it reproduces by seed, and produces bright red fruits in the late fall that often remain on the plant through the winter. Like its prickly pear cousins, it also reproduces from pieces caught on animals and dropped elsewhere, causing it to be compared to the famed chollas of the Joshua Tree National Park of California. This helps explain why O. leptocaulis ranges all the way from the Brazos to the east all the way to the Pacific Ocean.
One of the interesting aspects on O. leptocaulis is that it is one of the only cacti on the ranch that blooms in the evening to night, instead of blooming in the early morning as with the other species in the area. Between this habit, the size of the blooms, and the understandable concern more about the spines than the blooms, most people are surprised to see one blooming. They also tend to bloom much later in the year, around late May into June, when most of the more spectacular cactus blooms are long-gone and those cacti are more focused on producing fruit. That said, they gravitate toward insect pollinators, based mostly on their extreme luminance under UV illumination, but they apparently also offer a few drinks to hummingbirds as well.
Now, what few guides contain information on O. leptocaulis mention that the fruit are eaten by deer and other mammals, but you’d never know it based on the huge loads of fruit on mature plants. Prickly pears are eaten with gusto by everything from cattle to skunks. Horsecrippler fruit is preferred by birds, native peccary, and feral pigs, while the other indigenous barrel cactus save their attentions for small birds and possibly the occasional lizard or box turtle. In the last decade since first coming out to the ranch, though, I have yet to see any vertebrate touch a pencil cactus fruit. The invertebrates seem to enjoy them, though, as the cactus offers both hotel and cafeteria for various species of grasshopper and katydid. As to how they encourage seed spread, your guess is as good as mine, and this entails more trips to the ranch to investigate. Oh, the absolute agony.