The descriptive text, below the map, is from the Cornish Red Data Book (2009). The map on this web page depicts the organisms distribution and shows the records made pre-2000 and those made since.
Range & Status
Occurs in S. and C. Europe (reaching its northern limit in Britain), N. Africa, southern N. America, S. America (Uruguay) and Australia (as an introduction?). The British records are mainly in SE. England, from Worcestershire and E. Norfolk southwards, but also in the Isles of Scilly.
Known in the Isles of Scilly on all islands with cultivated land (Bryher, St. Agnes, St. Martin' s, St. Mary' s and Tresco). Probably somewhat under-recorded in Scilly because ripe spores are needed to distinguish this species from S. michelii Bellardi, which often grows with it.
Habitat & Ecology
In Scilly it is fairly common as a weed in flower fields, disappearing by mid-summer. Elsewhere in Britain it is known mainly as a weed of non-calcareous loamy or sandy soil in gardens, nurseries and fields. The species is dioicous but produces abundant sporophytes which mature in Scilly in at least May and June (from December to June elsewhere: Preston in Hill et al ., 1991).
Little information, but apparently not threatened in Scilly so long as traditional methods of cultivation continue in flower fields.
This species is listed on the UK BAP Priority Species list (2007).
I.J. Bennallick, S. Board, C.N. French, P.A. Gainey, C. Neil, R. Parslow, A. Spalding and P.E. Tompsett. eds. 2009. Red Data Book for Cornwall and the Isles of Scilly. 2nd Edition.Croceago Press.
The Cornish Red Data Book Project was led by the Cornwall and Isles of Scilly Federation for Biological Recorders (CISFBR). The full text and species accounts (minus the maps) are available on the CISFBR website.