Tarragon (Artemisia dracunculus), also known as estragon, is a species of perennial herb in the sunflower family. 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 centimeters (4–5 feet) tall, with slender branches. The leaves are lanceolate, 2–8 cm (1–3 in) long, and 1⁄8 - 3⁄8 in broad, glossy green, with an entire margin. The flowers are produced in small capitula 1⁄16 - 3⁄16 in diameter, each capitulum containing up to 40 yellow or greenish-yellow florets. French tarragon, however, seldom produces any flowers (or seeds). Some tarragon plants produce seeds that are generally sterile. Others produce viable seeds. Tarragon has rhizomatous roots that it uses to spread and readily reproduce.

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