Highfield Moss SSSI

Highfield Moss is situated 10km west of Leigh and 1km east of Lowton. It is managed by Lancashire Wildlife Trust and is a Site of Special Scientific Interest (SSSI), which means it’s been designated as a protected area for conservation purposes.

The site is bordered by farmland and intersected by the Liverpool to Manchester railway. It’s underlain by Triassic Scythian Sherwood sandstones and bears superficial glacial sand and gravel deposits in the area north of the railway and a narrow band to its south. However, south of the site mainly bears raised mire peat. A watercourse with two pools crosses the peat body.

Key habitats

  • Mixed valley mire communities on the peat
  • Acidic marshy grassland on the glacial deposits
  • Unimproved acidic grassland on the railway mound and cutting.

Although the site is relatively small, the peatland vegetation is the best remaining example of the mires, which once covered large areas of lowland Greater Manchester and Merseyside.

Ecology of the area

  • Mixed mire communities developed on deep peat include Sphagnum lawn, wet heath, tall fen, marginal ditch vegetation and open pools.
  • Areas of wet heath are dominated by purple moor-grass often with wavy hair-grass and with common cottongrass Eriophorum angustifolium, hare’s-tail cottongrass E. vaginatum, heather, cross-leaved heath Erica tetralix becoming locally common or co-dominant.
  • The small Sphagnum lawn which persists contains several species of bog moss including Sphagnum pappillosum and S. cuspidatum, elsewhere in the wet heath Sphagnum recurvum occurs.
  • The margins of the pools are characterised by soft rush with common cottongrass and common sedges.
  • The acidic marshy grassland is dominated by purple moor-grass, associated with wavy hair-grass. It’s also a stronghold for the rare marsh gentian Gentiana pneumonanthe. Petty whin Genista anglica are locally scattered.
  • Soft rush, common bent and lousewort Pedicularis sylvatica are locally common and less frequently species such as cross-leaved heath, heath rush, heather and tormentil occur.
  • Wavy hair-grass dominates the drier acidic grassland where mat-grass Nardus stricta, sweet vernal-grass, tormentil and heath-bedstraw are also abundant.
  • Bracken occurs on the western and northern edges of the site and there is a small stand of pedunculate oak and gorse scrub.

Several of the plants present are locally uncommon, including marsh gentian, petty whin, false fox-sedge, cross-leaved heath, lousewort and cranberry Vaccinium oxycoccus. Uncommon species such as star sedge Carex echinata, carnation sedge C. panicea, marsh pennywort and bulbous rush also occur.

A number of plant species which characterise the mixed mire community at this site have now disappeared from other relic peatlands in Greater Manchester and southern Lancashire as a result of land drainage.

Birds and insects

The pools support good dragonfly populations including the locally scarce black darter Sympetrum scoticum. The site also supports breeding and wintering bird populations.

© Wigan Council