close up of white flowers and green leaves of parthenium hysterophorus - santa maria or whitetop weed or carrot grass

allergen allergenic allergic allergies allergy asteraceae asthma bhajpa carrot close congress conjunctivitis dermatitis detailed details famine feverfew flora flower flowering flowers gajar ghans grass green hysterophorus leaf leaves maria parthenium perennial plant plants pollen pollens pollination rhinitis roadside santa seasonal structure tropical tropics weed weeds white whitetop