BSBI Species Accounts ArchiveParis quadrifolia
Tue, 08/10/2010 - 17:36 | 
markd
Common name: Herb Paris.
It is unlikely to be confused with any other species in the British flora (Tutin et al. 1980; Stace 1997). The only other member of this genus that occurs in Europe is P. incompleta (Jacqemyn, Brys & Hutchings 2008).
Chromosome No.: 2n = 60 (tetraploid) (Stace 2010) .
It is common throughout northern Europe and Asia as far as Siberia, but is rare in the Mediterranean region (Tutin et al. 1980; Sell & Murrell 1996). In Britain it is widespread but with a somewhat scattered distribution. It is absent from the Northern Isles, the Outer Hebrides and Ireland, and it is very scarce in westernmost parts (Preston, Pearman & Dines 2002). Its highest recorded altitude in Britain is 360 m, at Great Asby Scar (v.c. 69) and Garrigill (v.c. 70) (Pearman 2004).
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Most authors simply describe P. quadrifolia as a woodland plant and leave it at that. Flora Europaea (Tutin et al. 1980) says: ‘woods and other damp or shady places.’ Stace (op. cit.) states: in moist woods on calcareous soils. Jacqemyn, Brys & Hutchings (2008) list it as a constituent of the NVC communities W8 and W9, sometimes occurring in W12, W7 and W2. Crawley (2005) considers it to be a plant of sheltered oak/ash woods in Berkshire, and gives its NVC type as W12 Fagus sylvatica - Mercurialis perennis woodland, but Jacquemyn et al. (op. cit.) report it being found in Alnus glutinosa woodland there. It is widely considered to be an Ancient Woodland Indicator (e.g. Rackham 1986), but Taylor (in Preston, Pearman & Dines 2002) offers a slightly different view. He describes it as favouring the open stages of the coppice cycle and occurring in grikes on limestone pavement. He considers that it readily spreads into secondary woodland; a view echoed by Jacquemyn et al. (2008).
One unanswered question about P. quadrifolia is how it has managed to disperse so widely in Britain. Most reproduction is by vegetative means, and the seeds are believed not to travel far. But with such a specialised habitat requirement, it clearly has to cross inhospitable terrain to reach suitable locations. This suggests that it may have greater powers of dispersal than is currently known. Whether it is really declining or not is unclear from the evidence. It does not appear to have contracted in range, and the 10 km data may not be sufficiently detailed to warrant an analysis within its range.
Paris quadrifolia is too widespread to have any official rarity status and, although the New Atlas (ibid.) gives it a Change Index of -0.68, it is not considered threatened. In Scotland, however, it could be described as a rare plant.
- Crawley, M.J. 2005. The Flora of Berkshire. Brambleby Books, Harpenden.
- Jacquemyn, H., Brys, R. & Hutchings, M.J. 2008. Biological Flora of the British Isles: Paris quadrifolia L. Journal of Ecology 96, 833-844.
- Rackham O. 1986. A History of the Countryside. Phoenix, London.
Lockton, A.J. (date accessed). Species account: Paris quadrifolia. Botanical Society of the British Isles, bsbi.org.
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