NVC community CG7 (Festuca ovina - Hieracium pilosella - Thymus praecox/pulegioides grassland) is one of the calcicolous grassland communities in the British National Vegetation Classification system. It is one of three short-sward communities associated with heavy grazing, within the lowland calcicolous grassland group, and is regarded as the eastern counterpart of "typical" chalk grassland (community CG2).
It is a comparatively widely distributed community. There are five subcommunities.
Community composition
The following constant species are found in this community:
- Sheep's Fescue (Festuca ovina)
 - Mouse-ear Hawkweed (Hieracium pilosella)
 - Rough Hawkbit (Leontodon hispidus)
 - Wild Thyme (Thymus praecox) / Large Thyme (T. pulegioides)
 - Cypress-leaved Plait-moss (Hypnum cupressiforme)
 
The following rare species are also associated with the community:
- Field Wormwood (Artemisia campestris)
 - Purple Milk-vetch (Astragalus danicus)
 - Rare Spring-sedge (Carex ericetorum)
 - Wall Bedstraw (Galium parisiense)
 - Lizard Orchid (Himantoglossum hircinum)
 - Hutchinsia (Hornungia petraea)
 - Bur Medick (Medicago minima)
 - Sickle Medick (Medicago falcata)
 - Sand Lucerne (Medicago sativa ssp. varia)
 - Fine-leaved Sandwort (Minuartia hybrida)
 - Purple-stem Cat's-tail (Phleum phleoides)
 - Spring Cinquefoil (Potentilla neumanniana)
 - Sand Catchfly (Silene conica)
 - Spanish Catchfly (Silene otites)
 - Breckland Thyme (Thymus serpyllum)
 - Spiked Speedwell (Veronica spicata)
 - Spring Speedwell (Veronica verna)
 - Side-fruited Crisp-moss Pleurochaeta squarrosa
 - the lichen Bacidia muscorum
 - the lichen Buellia epigaea
 - the lichen Diploschistes scrupsos var. bryophilus
 - the lichen Fulgensia fulgens
 - the lichen Lecidea decipiens
 - the lichen Squamaria lentigera
 - the lichen Toximia caerulea var. nigricans
 - the lichen Toximia lobulata
 
Distribution
This community is found scattered throughout chalk grassland sites in southern England, particularly in The Brecks on the Norfolk/Suffolk border, with outlying clusters in the Yorkshire Wolds (also on chalk), and on Carboniferous limestone in Derbyshire and Mendip Hills.
Subcommunities
There are five subcommunities:
- the Koeleria macrantha subcommunity
 - the Cladonia spp. subcommunity
 - the Ditrichum flexicaule - Diploschistes scruposus var. bryophilus subcommunity
 - the Fragaria vesca - Erigeron acer subcommunity
 - the Medicago lupulina - Rumex acetosa subcommunity
 
References
- Rodwell, J. S. (1992) British Plant Communities Volume 3 - Grasslands and montane communities ISBN 0-521-39166-0 (hardback), ISBN 0-521-62719-2 (paperback)