Pulsatilla vulgaris (L.) Mill. - Plantlife

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educe trampling by visitors, Barnack Hills & Holes, Northamptonshire; (c) cages to protect transplants from rabbits (note clearance of vegetation from around the plant), Ancaster Valley, South Lincolnshire; and (d) effects of the reintroduction of grazing to the Devil’s Dyke, Cambridgeshire, following the erection of stock-proof fencing. 7.2 Ex situ Measures Plants of wild origin are known to be cultivated in the Oxford Botanic Garden and Kew’s garden at Wakehurst Place. Plants originating from Barnack Hills and Holes were also grown by Terry Wells at Monks Wood Experimental station between 1970 and 1980 for the purposes of research, some of which were transferred to his garden in Upwood. Many plants originating from wild British populations are likely to be cultivated in other private gardens. A small amount of viable seed is currently stored in the Kew Millennium Seed Bank at Wakehurst Place (Royal Botanic Gardens Kew, 2008). Pollen from the single Ledsham plant has been used to cross-pollinate five plants from Barnack Hills and Holes, with the intention of growing on plants for reintroduction to the wild site, but without success (A. Headley, pers. comm.). 7.3 Research Data Research is urgently required to assess genetic variation within English populations and the extent to which small population size, limited gene-flow (due to extreme population fragmentation), genetic drift and inbreeding depression are affecting the performance of English populations. Likewise studies that assess dispersal and pollination mechanisms, in particular the potential for dispersal via livestock and machinery, may provide valuable insights into gene-flow and how best to conserve Pulsatilla vulgaris in the future. Studies on the genetic relationships between British and continental populations would also be useful help to inform European conservation priorities. Research on the regeneration niche of Pulsatilla vulgaris is needed in order to establish the optimum conditions under which field germination and seedling establishment takes place. Further work is also needed to assess factors controlling the abundance of Pulsatilla vulgaris, in particular the affects of the removal of competitive dominance in grassland swards e.g. responses to environmental perturbations and the removal of dominant species and leaf litter (Bailey, 1996). Figure 15 – Fluctuations in the number of Pulsatilla vulgaris in fixed plots at Barnack Hills and Holes, Northamptonshire. Data supplied by Chris Gardner (Natural England). 34
7.4 Monitoring and the Common Monitoring Standard Traditionally Pulsatilla vulgaris has been monitored by simple counts of flowering ‘crowns’ or estimates based on densities in small areas (e.g. Tarpey, 1999). These provide an overall assessment of year to year variation but are limited for a number of reasons. First, ‘crowns’ do not represent discrete genets due to the production of offshoots close to parents. The total count is therefore likely to overestimate the total size of the population possibly by orders of magnitude. Second, grazing can have a marked influence on estimates especially on sites where livestock are present during the flowering period. Third, such counts do not take into account the life-stage structure of the population or whether recruitment is taking place through the production of seed, presence of juveniles, etc. Possible alternative approaches include counts within fixed plots as has been carried out at Barnack Hills and Holes in Northamptonshire since 1975 (Fig. 15). This should preferably include a number of demographic parameters, including the individuals in different lifestages, flowering performance, seed production etc., and relate these environmental variables such as sward height, % cover of bare ground, ‘hits’ on dominant grasses, etc. Simple counts of rosettes rather than flower stems is probably a more preferable performance parameter given the dramatic fluctuations in the numbers of flowers observed on some sites (e.g. Fig. 15). These are less affected by seasonal factors and grazing and therefore provide a more accurate assessment of the size of populations (Bailey, 1996). However, all these approaches are likely to be time consuming to carry-out and therefore dependent on available expertise, time and resources. 8 References Abbott, P.P. 2005. Plant Atlas of Mid-west Yorkshire. Yorkshire Naturalists’ Union. Aichele, D. & Schwegler, H.W. 1957. Die Taxonomie der Gattung Pulsatilla. Feddes Repertorium 60, 1-230. Akeroyd, J. 1993. Pulsatilla Miller, in T.G. Tutin, N.A. Burges, A.O. Chater, J.R. Edmondson, V.H. Heywood, D.M. Moore, D.H. Valentine, S.M. Walters, D.A. Webb (eds) Flora Europaea, Volume 1, Psilotaceae to Platanaceae, second edition. Cambridge University Press, Cambridge. Babbington, C.C. 1860. Flora of Cambridgeshire. J. van Voorst, London. Baker, J.G. 1906. North Yorkshire: Studies of its Botany, Geology, Climate and Physical Geography. Longmans, London. Bailey, C. 1996. An investigation into the factors influencing the distribution, relative abundance and genetic variation of Pulsatilla vulgaris at two sites in Bedfordshire. Unpublished MSc thesis, Imperial College, Wye. Böcher, T.W. 1934. Beiträge zur Zytologie der Gattung Anemone. Botanisk Tidsskrift 42, 183- 206. Bowen, H. 1968. The Flora of Berkshire. Holywell Press, Oxford. Bowen, H. 1997. Observations on Pulsatilla vulgaris. BSBI News 76, 37. Bowen, H. 2000. The Flora of Dorset. Pisces Publications, Newbury. Brewis, A., Bowman, P. & Rose, F. 1996. The Flora of Hampshire. Harley Books, Colchester. Campbell, B.D., Grime, J.P. & Mackey, J.M.L. 1992. Shoot thrust and its role in plant competition. Journal of Ecology 80, 633-641. Carter, H.H. 1967. Juniper Valley: some observations and problems. Reading Naturalist 19, 21-29. 35
Page 1 and 2: Pulsatilla vulgaris (L.) Mill. Pasq
Page 3 and 4: 1 Morphology, identification, taxon
Page 5 and 6: Pulsatilla is now generally accepte
Page 7 and 8: 2 Distribution and current status 2
Page 9 and 10: UK VU Declined from ca.130 to 18 lo
Page 11 and 12: English populations, the overall nu
Page 13 and 14: surviving in each year, and (c) the
Page 15 and 16: maturation before the male (andro-
Page 17 and 18: 3.1.6 Seed dispersal Achenes of Pul
Page 19 and 20: the sward and thereby determining t
Page 21 and 22: Table 6 - Chemical and mechanical a
Page 23 and 24: Figure 9 continued. Habitats of Pul
Page 25 and 26: Cavenham Heath) support extensive a
Page 27 and 28: Kalliovirta et al., 2006). There ar
Page 29 and 30: Losses to ploughing and quarrying c
Page 31 and 32: . (a) Sites in good condition, graz
Page 33: Quarry, Ancaster 1996 Most scratche
Page 37 and 38: Kalliovirta, M., Ryttäri, T. & Hei
Page 39 and 40: Warden, K. 2001. An investigation i
Page 41 and 42: 11 Annex 1 - site descriptions Desc
Page 43 and 44: Historically Pulsatilla has been re
Page 45 and 46: In the 1960s a small population occ
Page 47 and 48: introduced by the National Trust le
Page 49 and 50: 13 Annex 2 - changes in population
Page 51 and 52: Annex 3 continued. All sites Limest

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