Arboretum » Campus Plant Identification – Avery Hall and Benson Auditorium » Planter on south side of Benson Auditorium – Aloe barbarae, Euphorbia ‘Sticks On Fire’, Trichocereus pachanoi (San Pedro cactus), Agave attenuata variegate (Fox tail agave) Planter on south side of Benson Auditorium – Aloe barbarae, Euphorbia ‘Sticks On Fire’, Trichocereus pachanoi (San Pedro cactus), Agave attenuata variegate (Fox tail agave)