This species has naturalized in 34 states. As far north as Maine, it can overwinter as a self-sowing annual.
Where it is h...Read Moreardy, it's a suckering perennial shrub that can reach a height of 40'.
It's a heavy producer of light air-borne pollen which is highly allergenic. It's a common trigger for hayfever and asthma. In many people, it also causes a skin rash on contact. The seed pods are spiny.
In California, Florida, and Texas, it's on the official lists of species invasive of natural habitat.
Native to the eastern Mediterranean, east Africa, and India, it's now spread to most tropical areas around the world, where it's commonly considered invasive.
This species has naturalized in 34 states. As far north as Maine, it can overwinter as a self-sowing annual.
Where it is h...Read More