Children (9 direct children, 9 direct and indirect children):
Ferocactus cylindraceus subsp. lecontei
Ferocactus cylindraceus subsp. tortulispinus
Curly spined california fire barrel
Ferocactus cylindraceus cylindraceus
Ferocactus cylindraceus var. cylindraceus
Ferocactus cylindraceus var. lecontei
Ferocactus cylindraceus subsp. eastwoodiae
Ferocactus cylindraceus var. eastwoodiae
Ferocactus cylindraceus var. greenwoodiae
Ferocactus cylindraceus var. tortulispinus