An area of 16.63 acres (6.73 ha) has been declared an SSSI
(Site of Special Scientific Interest) for its unimproved neutral grassland of the
type crested dogs-tail Cynosuras cristatus, common knapweed Centaurea nigra
lowland hay meadow and pasture, and heath-grass Dantonia decumbens
sub-community.
Mill Meadows SSSI is comprised of five adjoining grassland units that
overlie Claygate beds (sandy clay or loam) and London Clay, sloping to the
north and separated by old hedge lines, some with ditches. The site is
bounded by housing, roads, a stream, semi-natural grassland, scrub and
secondary woodland. Although the site lacks any rare species it supports a
characteristic flora of a grassland type that is very much reduced within
the Essex landscape due to development and agricultural improvement.
The grassland is neutral to acid and dry to wet in character. It is composed
of a sward largely of red fescue Festuca rubra and common bent Agrostis
cappilaris within which Devil's-bit scabious Succisa pratensis, tormentil
Potentilla erecta and common knapweed Centaurea nigra are frequent. Locally
frequent to abundant are burnet saxifrage Pimpinella saifraga, betony
Stachys officinalis and field wood-rush Luzula campestris. Other species
include harebell Campanula rotundifolia, yellow rattle Rhinanthus minor,
common spotted orchid Dactylorhoza fuschii, common birds-foot-trfoil Lotus
cornicultas and pignut Conopodium majus.
To the north there are several flushed areas that support a similar flora to
that already noted but with the additions of plants including sharp-flowered
rush Juncas acutiflorus, angelica Angelica sylvestris, greater
birds-foot-trefoil Lotus pendunculatus, marsh thistle Cirsium palustre,
sneezwort Achillia ptarmica, cuckooflower Cardimine pratensis, ragged robin
Lycnis flos-cuculi and common marsh-bedstraw Galium palustre.
