Lowland Dry Acid Grassland

Lowland Dry Acid Grassland -

Current Status

Acid grassland occurs on free-draining, nutrient-poor soils on sand or gravel substrates, and is characterised by species such as common bent, sheep's sorrel, heath bedstraw and tormentil. Parched acid grassland, which becomes excessively dry in summer, may support a number of uncommon, ephemeral species, such as small cudweed and bird's-foot.

Acid grassland in Kent occurs in old pastures and commons, parkland, in woodland rides and glades, and, rarely, on old dune and shingle systems. It is largely confined to the High Weald and Greensand Ridge, though significant areas occur at Dungeness, and on Tertiary and Quaternary sands and gravels which overlie the chalk of the North Downs.

The 2003 Kent Habitat Survey shows 375 ha of acid grassland in the county (the Phase 1 survey of the early 1990s gives only 737.5 ha; the reasons for this difference are not clear but may be due, inter alia, to differences in the habitat definitions used by the two surveys or improved accuracy of mapping). This area is made up of a large number of small blocks: half the total area of Kent's acid grassland is in blocks of 4 ha or less, and the largest continuous block comprises 50 ha of Knole Park. Recent action to restore heathland and associated habitats at Pembury and The Blean will have increased the area of acid grassland in the county, though accurate figures for the area restored are not currently available.

The 2003 Kent Habitat Survey shows 375 ha of acid grassland in the county (the Phase 1 survey of the early 1990s gives only 737.5 ha; the reasons for this difference are not clear but may be due, inter alia, to differences in the habitat definitions used by the two surveys or improved accuracy of mapping). This area is made up of a large number of small blocks: half the total area of Kent's acid grassland is in blocks of 4 ha or less, and the largest continuous block comprises 50 ha of Knole Park. Recent action to restore heathland and associated habitats at Pembury and The Blean will have increased the area of acid grassland in the county, though accurate figures for the area restored are not currently available.

Factors

Although changes to acid grassland, both nationally and locally, are difficult to assess there is little doubt that the habitat is becoming scarcer and more fragmented. Key factors appear to be:

  • Agricultural improvement of grassland.

  • Lack of appropriate management (such as grazing) leading to rank grassland or invasion by bracken and scrub, particularly on commons.

  • Lack of ride and glade management affecting acid grassland patches within woodland complexes.

  • Direct loss to development such as quarrying, road building and housing.

  • Potential creation of new acid grassland habitat as a result of quarrying.

Current Action

Recent action to restore heathland and associated habitats at Pembury and The Blean will have increased the area of acid grassland in the county, though accurate figures for the area restored are not currently available.

Objectives

  1. Maintain the extent of all existing acid grassland sites.

  2. Increase the overall area extent of acid grassland and reduce habitat fragmentation.

  3. Secure appropriate management of all SSSI and Local Wildlife Site (SNCI) acid grassland.

Relevant Habitat Action Plans

The relevant UK Habitat Action Plans:

The relevant UK Species Action Plans:

The relevant Kent Habitat Action Plans:

  • Coastal Sand Dunes
  • Coastal Vegetated Shingle
  • Lowland Wood-Pasture & Parkland
  • Mixed Broadleaved Woodland & Plantations on Ancient Woodland Sites