Erigeron greenei is a North American species of flowering plant in the family Asteraceae known by the common name Greene's narrow-leaved daisy .
Erigeron greenei is a perennial herb up to 90 cm (3 feet) tall, producing a large taproot. Leaves are narrow, up to 60 mm (2.4 inches) long but less than 2 mm (0.08 inches) across. The plant sometimes produces only one flower heads per stem, sometimes groups of as many as 5. Each head contains as many as numerous yellow disc florets but no ray florets. The species grows in open coniferous woodlands, frequently in serpentine soil.[1]
The species was first described by Asa Gray in 1884 as a variety of Erigeron inornatus, E. inornatus var. angustatus. In 1885, Edward Lee Greene raised the variety to the full species Erigeron angustatus. In 1992, Guy L. Nesom made it a variety of Erigeron reductus, E. reductus var. angustatus.[2] Then in 2004, Nesom published the replacement name Erigeron greenei, in the belief that Erigeron angustatus had already been published before Greene's use.[3], Plants of the World Online regarded Nesom's species name as superfluous, treating the taxon as the variety Erigeron reductus var. angustatus.[2]
Erigeron greenei is an uncommon species with a restricted range. It has been found only in California in the region north of San Francisco Bay, from Sonoma and Napa Counties north as far as Siskiyou County.[4]