Santa Maria!, Parthenium hysterophorus

This was just an innocent little roadside weed. It was a windy day , and we had places to go, so it wasn't practical to spend time getting up close and personal. Good thing. When you say Santa Maria, say it with emphasis. Sort of like, "Holy c---!". Mere contact with it causes dermatitis and respiratory malfunction. It also causes pollen allergies, which is very unusual for a plant in this family. It leaves allopathic chemicals behind that inhibit the growth of other plants. The plan seems to be to take over grazing areas, kill the other plants, and force the herbifores to eat Maria. After they're gone it can just form a big happy monoculture! Santa Maria! came to us from the American tropics and so far has attacked AL, AR, CT, DE, FL, GA, HI, IL, KS, LA, MA, MD, MI, MO, MS, NJ, NY, OH, OK, PA, SC, TX, and VA. Monroe Co FL, 1/26/13. Aster family, Asteraceae.