Allison M. andAusden M. (2006) Effects of removing the litter and humic layers on heathland establishment following plantation removal. Biological Conservation 127, 177–182.
Arnold M.L. (1994) Natural hybridization and Louisiana irises. Defining a major factor in plant evolution. BioScience 44, 141–147.
Arnold M.L. (1997) Natural hybridization and evolution. Oxford, Oxford University Press.
Bannister P. (1965) Biological flora of the British Isles. Erica cinerea L. Journal of Ecology 53, 527–542.
Bannister P. (1966) Biological flora of the British Isles. Erica tetralix L. Journal of Ecology 54, 795–813.
Bekker R.M., Oomes M.J.M. andBakker J.P. (1998) The impact of groundwater level on soil seed bank survival. Seed Science Research 8, 399–404.
Bossuyt B. andHermy M. (2003) The potential of soil seedbanks in the ecological restoration of grassland and heathland communities. Belgian Journal of Botany 136, 23–34.
Bouck A., Peeler R., Arnold M.L. andWessler S.R. (2005) Genetic mapping of species boundaries in Louisiana irises using IRRE retrotransposon display markers. Genetics 171, 1289–1303.
Britton A.J., Marrs R.H., Carey P.D. andPakeman R.J. (2000) Comparison of techniques to increase Calluna vulgaris cover on heathland invaded by grasses in Breckland, south east England. Biological Conservation 95, 227–232.
Bullock J.M. andClarke R.T. (2000) Long distance seed dispersal by wind: measuring and modelling the tail of the curve. Oecologia 124, 506–521.
Chapman S.B. (1975) The distribution and composition of hybrid populations of Erica ciliaris L. and Erica tetralix L. in Dorset. Journal of Ecology 63, 809–823.
Chapman S.B. andRose R.J. (1994) Changes in the distribution of Erica ciliaris L. and E. × watsonii Benth. in Dorset, 1963–1987. Watsonia 20, 89–95.
Chapman S.B., Clarke R.T. andWebb N.R. (1989) The survey and assessment of heathland in Dorset, England, for conservation. Biological Conservation 47, 137–152.
Eshel A., Henig-Sever N. andNe'eman G. (2000) Spatial variation of seedling distribution in an east Mediterranean pine woodland at the beginning of post fire succession. Plant Ecology 148, 175–182.
Fischer M. andMatthies D. (1998) Experimental demography of the rare Gentianella germanica: seed bank formation and microsite effects on seedling establishment. Ecography 21, 269–278.
Gay P.A. (1957) PhD thesis, University of London.
Gay P.A. (1960) A new method for the comparison of populations that contain hybrids. New Phytologist 59, 218–226.
Gillham D.A. (1980) . PhD thesis, University of Liverpool.
Gimingham C.H. (1972) Ecology of heathlands. London, Chapman & Hall.
Grant V. (1949) Pollination systems as isolating mechanisms in angiosperms. Evolution 3, 82–97.
Grant V. (1975) Genetics of flowering plants. New York, Columbia University Press.
Johnston J.A., Arnold M.L. andDonovan L.A. (2003) High hybrid fitness at seed and seedling life history stages in Louisiana irises. Journal of Ecology 91, 438–446.
Levin D.A., Francisco-Ortega J. andJansen R.K. (1996) Hybridization and the extinction of rare plant species. Conservation Biology 10, 10–16.
Mitchell R.J., Marrs R.H. andAuld M.H.D. (1998) A comparative study of the seedbanks of heathland and successional habitats in Dorset, Southern England. Journal of Ecology 86, 588–596.
Neyraut M. (1900) Nouvelle localité française de l'Erica watsoni et de quelques formes ou variétés de l'Erica tetralix et de l'Erica ciliaris. Bulletin de la Société Botanique de France 17, 326–329.
Odion D. andTyler C. (2002) Are long fire-free periods needed to maintain the endangered, fire-recruiting shrub Arctostaphylos morroensis (Ericaceae)? Conservation Ecology 6 (2), 4. http://www.consecol.org/vol6/iss2/art4/.
Pakeman R.J. andMarshall A.G. (1997) The seedbanks of the Breckland heaths and heath grasslands, eastern England, and their relationship to the vegetation and the effects of management. Journal of Biogeography 24, 375–390.
Perring F.H. andSell P.D. (1968) Critical supplement to the atlas of the British flora. London, Thomas Nelson & Sons.
Putwain P.D. andRae P. (1988) Heathland restoration: A handbook of techniques. Southampton, Environmental Advisory Unit, Liverpool University and British Gas plc.
Pywell R.F. (1993) . PhD thesis, University of Liverpool.
Pywell R.F., Putwain P.D. andWebb N.R. (1997) The decline of heathland seed populations following the conversion to agriculture. Journal of Applied Ecology 34, 949–960.
Pywell R.F., Pakeman R.J., Allchin E.A., Bourn N.A.D., Warman E.A. andWalker K.J. (2002) The potential for lowland heath regeneration following plantation removal. Biological Conservation 108, 247–258.
Rodwell J.S. (1991) British plant communities. Volume 2. Mires and heaths. Cambridge, Cambridge University Press.
Rose R.J., Bannister P. andChapman S.B. (1996) Biological flora of the British Isles: Erica ciliaris L. Journal of Ecology 84, 617–628.
Rose R.J., Webb N.R., Clarke R.T. andTraynor C.H. (2000) Changes on the heathlands in Dorset, England between 1987 and 1996. Biological Conservation 93, 117–125.
Stace C.A. (1975) Hybridization and the flora of the British Isles. London, Academic Press.
ter Heerdt G.N.J., Schutter A. andBakker J.P. (1999) The effect of water supply on seed-bank analysis using the seed-emergence method. Functional Ecology 13, 428–430.
Thompson K. andGrime J.P. (1979) Seasonal variation in the seed banks of herbaceous species in ten contrasting habitats. Journal of Ecology 67, 893–921.
Thompson K., Bakker J.P. andBekker R.M. (1997) The soil seedbanks of North West Europe: Methodology, density and longevity. Cambridge, Cambridge University Press.
Valbuena L. andTrabaud L. (2001) Contribution of the soil seed bank to post-fire recovery of a heathland. Plant Ecology 152, 175–183.
Walker K.J., Stevens P.A., Stevens D.P., Mountford J.O., Manchester S.J. andPywell R.F. (2004a) The restoration and re-creation of species-rich lowland grassland on land formerly managed for intensive agriculture in the UK. Biological Conservation 119, 1–18.
Walker K.J., Pywell R.F., Warman E.A., Fowbert J.A., Bhogal A. andChambers B.J. (2004b) The importance of former land use in determining successful re-creation of lowland heath in southern England. Biological Conservation 116, 289–303.
Wigginton M.J. (1999b) British red data books: Vascular plants. (3rd edition). Peterborough, UK, Joint Nature Conservation Committee.
Wolf D.E., Takebayashi N. andRieseberg L.H. (2001) Predicting the risk of extinction through hybridization. Conservation Biology 15, 1039–1053.