Ptilimnium capillaceum

Herbwilliam
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Asterids
Order:	Apiales
Family:	Apiaceae
Genus:	Ptilimnium
Species:	P. capillaceum
Binomial name
	Ptilimnium capillaceum; (Michx.) Raf. (1830)
	General range of Ptilimnium capillaceum
Synonyms
	Ammi capillaceum Michx. (1803) ; Discopleura capillacea (Michx.) DC. (1829) ; Sison capillaceum (Michx.) Spreng. (1824) ; Ammi majus Walter (1788) ; Ammi rubricaule Hornem. (1813) ; Discopleura juncea (Raf.) Steud. (1840) ; Discopleura major Britton, Sterns & Poggenb. (1888) ; Ptilimnium junceum Raf. (1830) ; Sison rubricaule (Hornem.) Eaton & Wright (1840) ;

Ptilimnium capillaceum, known by the common name of herbwilliam, is a member of the carrot family, Apiaceae. It is a perennial herb, native to the eastern United States, from Texas to Massachusetts.