Trichocereus in flower today

Wow that thing is huge I've seen that pic before..

There is a really old guy that has an old run down cacti nursery near my place, he had an enormous very woody plant in his front yard. The trunk is very fat, two people with arms warped around from each side would touch their hands!!! It is as tall as a gum tree. No idea what the species is, I saw it a while ago.