https://edis.ifas.ufl.edu/ep448
Ragweed parthenium (a.k.a. parthenium weed, Santa Maria feverfew, congress grass, carrot weed, white top, etc.), a member of the Asteraceae (Compositae) family, is native to Mexico and Central and South America and is becoming an increasingly troublesome weed around the world (Figure 1). Considered one of the world's most invasive weeds, it is an increasing problem in Africa (McConnachie et al. 2011). It is possibly the worst weed in both rural and urban areas of India (Kohli et al. 2006) and is also a weed of national significance in Australia (Evans 1997; National Weeds Strategy Executive Committee 2001).