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Notes - Isolepis cernua: do different? / Old and mysterious record of Senecio paludosus 13Isolepis cernua: do different?SIMON HARRAp, 1 Norwich Road, Edgefield, Norfolk, NR24 2RP. harrap@onetel.netIsolepis cernua (Slender Club-rush) has anintriguing distribution in Britain, being confinedto the coastal regions of Ireland, the west coastof Britain from the Outer Hebrides south toCornwall, and then along the south coast toHampshire and the Isle of Wight. It is alsolocally common inland in the New Forest, butwhat is an otherwise perfect 'Oceanic' or'Atlantic' distribution is spoilt by its occurrencein both West and East Norfolk (New Atlas). InNorfolk it was unknown prior to 1914, but hassince been recorded from eight sites: in WestNorfolk from Scarning and Potter's Fens and inEast Norfolk from Holt, Booton Common,Buxton Heath, Beeston Bog, Bryants Heath(Felmingham) and Hevingham (petch & Swann1968); it was noted as still being present atBeeston and Buxton Heath by Beckett, Bull &Stevenson (1999). The record for Holt is notlocalised, but a manuscript book held by thebiology department of Gresham's School, Holt,has a record of the species for 1926 by C.P.Petch (then a pupil at Gresham's) for HoltLowes, an area of heath, secondary scrub andfen that was set aside by the 1807 Enclosure Actas a 'Poors Allotment' and is now an SSSI.Despite fairly intensive recording at HoltLowes, Isolepis cernua was not, to my knowledge,found there again until I came across it inJune 2002. In the preceding period substantialmanagement work had been undertaken by theNorfolk Wildlife Trust and this included thefelling and removal of secondary woodland thathad invaded former areas of open mire vegetation.It was in one such area (at TG089.373)that I found several plants that I suspected to be1. cernua (having seen the species previously atBeeston Bog). Keen to be sure ofthe identification,I examined them critically, and wasconvinced with the exception of one feature.Rather than having two stamens, the plants hadthree (see Colour Section, Plate 1. Fig. 1). In thedescription of the genus Isolepis, Stace (1991)gives the number of stamens as '1-2' and this isrepeated in Stace (2004). Indeed, the other referencesthat I had to hand give the number ofstamens in Isolepis as 1-2 (CTM) or two (Rose1989). Notwithstanding this discrepancy, Iidentified the plants as 1. cernua based on theappearance of the mature nut, which was warmbrown, minutely dotted with minute papillae (alittle darker brown, with prominent ribs in1. setacea) (see Colour Section, Plate 1. Fig 2).My interest in Slender Club-rush aroused, Ihave been looking more closely at the speciesand have found that plants from BeestonCommon also have three stamens per floret (seeColour Section, Plate 1. Fig. 3). I would haveclaimed that this was another case of Norfolk's'do different' approach but plants seen in theNew Forest (Boundway Hill) in 2004 alsoshowed three stamens!I have also noticed that another, albeit lesscritical, identification feature appears to beunreliable. Stace (2004) states that the mainbract is 'at most only slightly longer than inflorescence'and this is also a key character in Rose(1989), the only other easily available referenceto the genus. This character is far from infallible,however, as at least occasionally somespikes on Norfolk plants have a 'stem' (i.e. mainbract) that can extend well beyond the spikelet.(See Colour Section, Plate 1. Fig. 4)References:BECKETT, G., BULL, A. & STEVENSON, R. 1999. AFlora of Norfolk. Privately published.CLAPHAM, A.R., TuTIN, T.G. & MOORE, D.M. 1987.Flora of the British Isles. Third Edition. Cambridge,CUP.PETCH, C.P. & SWANN, E.L. 1968. Flora of Norfolk.Norwich: Jarro1d.ROSE, F. 1989. Colour Identification Guide to theGrasses, Sedges, Rushes and Ferns of the BritishIsles and north-western Europe. London: Viking.STACE, C. 1991. New Flora of the British Isles. Cambridge:CUP.STACE, C.A. 2004. Interactive Flora of the BritishIsles. ET! (DVD-ROM).An old and mysterious record of Senecio paludosus from v.c. 20TREVOR JAMES, Recorder: v.c. 20: Herts., 56 Back Street, Ashwell, Baldock, Herts., SG7 5PEResearchers compiling data on Senecio paludosus(Fen Ragwort) for conservationprogrammes came across a specimen of this rareplant buried in the herbarium of the RoyalBotanic Garden, Edinburgh, claiming to comefrom Hertfordshire. However, it was not untilDr Stuart Warrington of the National Trust drewmy attention to this reference that news of its