Aster lanceolatus, Willd.

10. A. lanceolatus Willd. View in CoL , op. cit. 2050 (1803)

(incl. A. tradescantii auct. eur., non L.).

Perennial 50-130 cm. Stem green, sometimes tinged with purple. Leaves lanceolate to linearlanceolate, glabrous, not auriculate at base, entire or obscurely toothed. Capitula in a rather narrow panicle, often arranged unilaterally on the branches. Involucral bracts in several rows, the longest 4-5-5 mm, the outer shorter than the inner, not mostly herbaceous, appressed. Ligules white or sometimes violet-blue, not more than 1 mm wide. River-banks and waste ground. Naturalized in C. & W. Europe. [Au Be Br Cz Ga Ge He Ho Hs Hu It Ju Lu No Po Rm.] (North America.)

Very variable in habit; variants with numerous small leaves in the inflorescence and small capitula have often been incorrectly assigned to A. tradescantii L.

The following two species from North America, closely related to 10, have been reported to occur in France but are perhaps not established: A. lateriflorus (L.) Britton, Trans. New York Acad. Sci. 9: 11 (1889), with patent or recurved inflorescence-branches and very unequal involucral bracts; and A. dumosus L. , Sp. Pl. 873 (1753), with a much-branched inflorescence and the longest involucral bracts 3-5-5 mm.

A. patulus Lam. , Encycl. Méth. Bot. 1: 308 (1783), said to be like 7 but with the leaves entire, not amplexicaul, and the involucral bracts as in 10, is also reported as doubtfully established in France. It is presumably derived from species from North America.