Cephalocereus columna-trajani

Cephalocereus columna-trajani grows with non-branching green shoots and reaches heights of 6 to 10 meters with diameters of up to 40 centimeters. There are 16 to 26 ribs, which are almost completely divided into cusps by transverse furrows. Abundant white, silky hairs emerge from the white areoles near the tip of the shoot. The 5 to 8 downward-facing, stiff central spines are grayish and up to 8 centimeters long. The 14 to 18 white marginal spines are up to 1 centimeter long. The clearly lateral, narrow, 2 to 3 meter long pseudocephalium extends to the top of the shoot and is usually directed north. It consists of yellowish, woolly hairs 4 to 6 centimeters long. The tubular to bell-shaped flowers are white to light yellow and have a length of up to 7.5 centimeters and the same diameter.

Cephalocereus columna-trajani is found in xerophyllous scrub habitat in the Mexican states of Oaxaca and Puebla at elevations between 600 and 1800 meters, where it forms dense forests. Plants are found growing along with Cephalocereus tetetzo, Coryphantha pallida, Mammillaria haageana and Mammillaria mystax.