Ageratina adenophora (Spreng.) R.M. King & H. Rob.

Ageratina adenophora (Spreng.) R.M. King & H. Rob.. Ageratina adenophora, commonly known as Crofton weed, is a species of flowering plant in the family Asteraceae native to Mexico. Originally grown as an ornamental plant, it has become invasive into farmland and bushland worldwide. It is toxic to horses, which develop a respiratory disease known as Numinbah horse sickness after eating it.