St Michael's graveyard was probably originally of vegetation type; chalk grassland. Chalk grasslands, also known as chalk downlands, are a distinctive and ecologically significant habitat found primarily across southern England and also in Derbyshire. These habitats flourish on thin, nutrient-poor soils overlying chalk or limestone bedrock. They form landscapes of gentle hills and open spaces characterised by remarkable biodiversity (Rodwell, 1992). The unique combination of geological and climatic conditions in chalk grasslands supports a rich variety of plants, insects, fungi, birds, and mammals, making them a vital ecological resource.
One of the defining characteristics of chalk grasslands is their species-rich vegetation. The alkaline nature of the chalk soil limits the availability of certain nutrients, particularly phosphorus and nitrogen, creating an environment where only specialised plant species thrive (Wilson et al., 2012). This restriction on nutrients reduces competitive dominance by any one species, promoting remarkable plant diversity.
Notable plant species include cowslip (Primula veris), salad burnet (Sanguisorba minor), horseshoe vetch (Hippocrepis comosa), wild thyme (Thymus polytrichus), greater knapweed (Centaurea scabiosa), quaking grass (Briza media), and numerous orchids, including bee orchid (Ophrys apifera), pyramidal orchid (Anacamptis pyramidalis), common spotted orchid (Dactylorhiza fuchsii), and fragrant orchid (Gymnadenia conopsea). Additional significant species include clustered bellflower (Campanula glomerata), rockrose (Helianthemum nummularium), common bird's-foot trefoil (Lotus corniculatus), and wild marjoram (Origanum vulgare) (Preston et al., 2002).
Mycorrhizal fungi play a crucial role in sustaining the biodiversity and ecological health of chalk grasslands. These fungi form symbiotic relationships with plant roots, significantly enhancing plants' ability to absorb water and nutrients (Smith & Read, 2008). Orchids, in particular, depend entirely on their fungal partners for seed germination and survival, demonstrating the critical importance of underground fungal networks in these habitats (McCormick et al., 2018).
In addition to botanical richness, chalk grasslands support an array of insect life, most notably butterflies and bees. Butterfly species such as the Chalkhill Blue (Polyommatus coridon) and Adonis Blue (Polyommatus bellargus) depend exclusively on chalk grassland flora, making these habitats essential for their survival (Thomas & Lewington, 2014). Additionally, these habitats provide nesting and feeding grounds for ground-nesting birds such as skylarks (Alauda arvensis) and meadow pipits (Anthus pratensis).
Human activity, however, has profoundly impacted chalk grasslands. Agricultural intensification, urbanisation, and abandonment of traditional management practices such as grazing or hay cutting have dramatically reduced their extent (Jefferson & Robertson, 2000). Active management, typically involving grazing by sheep or cattle and removal of scrub, is crucial for maintaining these landscapes. Conservation efforts have intensified in recent decades, recognising chalk grasslands not only as reservoirs of biodiversity but also as integral components of cultural heritage (UK Biodiversity Action Plan, 2007).
Protecting and restoring chalk grassland habitats has broader implications, including carbon storage, soil protection, and ecological resilience (Natural England, 2012). As such, chalk grasslands represent not just ecological diversity, but critical natural infrastructure for addressing environmental challenges in an increasingly uncertain climate.
In conclusion, chalk grasslands are biologically rich and culturally significant landscapes deserving careful stewardship and conservation. Preserving these delicate ecosystems ensures the survival of numerous species, maintains ecological stability, and sustains the heritage of regions shaped profoundly by their presence.
Good examples near the Heene area are:
• Cissbury Ring
• Mount Caburn near Lewes
• Devil’s Dyke
• Anchor Bottom
These are all excellent chalk grassland sites, and areas within them might be referred to locally as “chalk meadowland.”
Vegetation types are not really discussed at school although they feature in ecology undergraduate and postgraduate courses. If anyone wants to read an engaging introduction to this subject material, I can recommend:
By John Brownbill (and a friend) April 2025
References:
- Jefferson, R.G., & Robertson, H.J. (2000). Lowland grassland management handbook. English Nature.
- McCormick, M.K., Jacquemyn, H., & Whigham, D.F. (2018). Orchid Mycorrhizal Interactions. Journal of Ecology, 106(5), 1806-1820.
- Natural England. (2012). Natural England Commissioned Report NECR106.
- Preston, C.D., Pearman, D.A., & Dines, T.D. (2002). New Atlas of the British and Irish Flora. Oxford University Press.
- Rodwell, J.S. (1992). British Plant Communities Volume 3: Grasslands and Montane Communities. Cambridge University Press.
- Smith, S.E., & Read, D.J. (2008). Mycorrhizal Symbiosis (3rd ed.). Academic Press.
- Thomas, J., & Lewington, R. (2014). The Butterflies of Britain and Ireland. British Wildlife Publishing.
- UK Biodiversity Action Plan. (2007). Priority Habitat Descriptions.
- Wilson, J.B., Peet, R.K., Dengler, J., & Pärtel, M. (2012). Plant species richness: the world records. Journal of Vegetation Science, 23(4), 796-802.