Artemisia sieversiana Ehrh. (N and C-As.) – An exceptional and probably ephemeral grain alien. Regularly recorded by roadsides in the port area in Gent since 2011 but probably depend on permanent re-introduction of seeds. Perhaps overlooked before.
Artemisia sieversiana is closely related with and very reminiscent of A. absinthium. It is an annual or biennial (vs. perennial) with larger heads (4-6 mm across, vs. 2-3 mm) and nutlets (1,2-2 mm long), leaves that are more or less triangular in outline with more acute leaf lobes and a deeply grooved, nearly angled stem. It is well-known for instance in the Czech Republic (Hejný 1964) and Ukrain (Mosyakin 1990).
Hejný S. (1964) Artemisia sieversiana Willd., eine neue eingeschleppte Art in der Tschechoslowakei. Preslia 36: 392-402.
Mosyakin S.L. (1990) New and noteworthy alien species of Artemisia L. (Asteraceae) in the Ukrainian SSR. Ukr. Botan. Zhurn. 47(4): 10-13.