Tarragon (artemisia dracunculus), also known as estragon, is a species of perennial herb in the family asteraceae. it is widespread in the wild across much of eurasia and north america, and is cultivated for culinary and medicinal purposes.one subspecies, artemisia dracunculus var. sativa, is cultivated for use of the leaves as an aromatic culinary herb. in some other subspecies, the characteristic aroma is largely absent. the species is polymorphic. informal names for distinguishing the variations include "french tarragon" (best for culinary use), "russian tarragon", and "wild tarragon" (covers various states). tarragon grows to 120–150 centimetres (4–5 feet) tall, with slender branches....

Source: Wikipedia