Senna septemtrionalis

Senna septemtrionalis, commonly known as arsenic bush, is a species of flowering plant in the family Fabaceae and is native to Central America, the southern United States and Mexico, but is naturalised in many other countries. It is an erect shrub with pinnate leaves, with four or five pairs of egg-shaped leaflets, and yellow flowers arranged in groups of five to eight, usually with seven fertile stamens and four staminodes in each flower.