Pachycereus pringlei
Description:
one of the most massive cacti, stout branching tree, the olive green columns to 16 inches, with 10-16 prominent but rounded ribs, closely studded by large oval areoles with short white or grayish wool especially toward apex, numerous ash-gray radials and 1-3 central spines at first reddish, afterwards gray; bell-shaped flowers, greenish-red outside, white inside.