Cacti Part 9 ~ Glory of Texas (Thelocactus bicolor)

The Glory of Texas cactus is another species that is the only one in its genus living in the Trans-Pecos. It is widely regarded as having the most beautiful blossom of all the cacti in Texas, a view with which it would be difficult to argue. Standing 3 to 7 inches tall, and growing to slightly 4 inches in diameter, this plant is easy to see, even when not in bloom.

No other Texas cactus has spine characteristics like this one. The upper third of the stem sports spines that look something like wood shavings. These spines are flattened and grow from 2 to 5 inches long. The central and some radial spines are bi- or even tri-colored. The pinkish to reddish color covers the middle of the spine. The remaining parts are straw-colored.

This cactus is ribbed. Ribs may be straight or spiraled and number 813. They look to have been made by fusing tubercles together. In older plants and with good rains, the ribs are spread apart, and it becomes easier to see the plant’s spines.

_MG_3699-Thelocactus bicolor
Flowers can be expected to occur between March and September, particularly after rains. The blossoms are between 2 and 5 inches in height and diameter. Tepals are reflexed with more pigment at the distal end of each tepal than at the center. They are a brilliant magenta; anthers are yellow with red-to-yellow stigma lobes. Flowers open mid-morning and remain open until afternoon, closing at night. They may reopen the next day, but that does not always occur.

Fruits are roughly ovoid, ¾ inch long at their largest. Fringed scales cover the fruit which dries out rapidly after reaching maturity.

Glory of Texas cacti are uncommon throughout their range, a situation made more acute by the fact that they are highly prized among collectors and are heavily harvested for the illegal cactus trade.

Thelocactus bicolor
The plants prefer silty to gravelly soils on level ground. They are particularly abundant on the Boquillas limestone formations that characterize so much of the basin terrains in the Big Bend area. It can be difficult to find one in bloom because of the short blooming period for each blossom. When one is in bloom, it would be hard to miss.




About aneyefortexas

Retired writer/teacher/photographer, now photographing the Chihuahuan Desert at the Big Bend Ranch State Park, Texas.
This entry was posted in Big Bend Ranch State Park, cacti, plant, Plants, Texas. Bookmark the permalink.

1 Response to Cacti Part 9 ~ Glory of Texas (Thelocactus bicolor)

  1. Luiza McKaughan says:


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