 "Sphecius grandis" has very similar nesting and feeding habits to other members of its genus, most notably "Sphecius speciosus".As with "S. speciosus", the female hunts for cicadas in low tree trunks, helped by the calls of the cicada males, and paralyses the insect by piercing the central nervous system with her stinger.She drags the cicadas back to her nest to place them in brood cells in which she eventually lays one egg per cell.