Lowland Heathland and Dry Acid Grassland
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SUFFOLK BIODIVERSITY PARTNERSHIP PRIORITY HABITAT FACTSHEET 7 Lowland Heathland and Dry Acid Grassland Definition Note: most heathland in Suffolk is made up of a matrix of dry acid grassland with some dwarf shrub and scrub communities. The two Priority Habitats have therefore been combined in this factsheet. Occurs on nutrient-poor, generally free-draining soils with pH ranging from 4 to 5.5 overlying acid rocks or superficial deposits such as sands and gravels. Found below an altitude of 300 metres. Contains dwarf shrub layer of various heights and structures plus additional features such as scattered trees and scrub, areas of bare ground, bracken, Coastal Sandlings and dry acid heathland at Blaxhall Common. areas of acid grassland, lichens, gorse and wet Image: Steve Aylward heaths. Dry Acid Grassland Characterised by species-poor plant community dominated by Sheep’s Fescue, Sheep’s Sorrel and Common Bent. Other species which are often present include Sand Sedge, Wavy Hair Grass, Tormentil and Heath Bedstraw. Suffolk Heathland In the coastal Sandlings heaths, the vegetation includes the dry acid grassland species above as well as dwarf shrubs (Heather, Gorse and Broom), Climbing Corydalis, bracken, scrub and trees. In Breckland, the vegetation reflects the mix of acid Cladonia lichen heath at Westleton. and chalky soils, producing a unique habitat in Image: Charles Cuthbert Britain. It has some similarities with the Steppes of eastern Europe. Typical plants include speedwells, Breckland Thyme and Spanish Catchfly. Smaller areas of dry acid grassland are found on stretches of vegetated shingle along the coast and on sand/ gravel deposits in the central Suffolk clay- lands e.g. in the Upper Waveney Valley at Wortham Ling and Redgrave and Lopham Breckland - Deadman’s Grave. Image: Ben Heather Fens. 1 IMPORTANCE FOR WILDLIFE Lowland heathland supports specialised and often rare wildlife. Birds Several bird species of conservation concern use this habitat for breeding or wintering such as Woodlark, Stone-curlew, Nightjar, Green Woodpecker, Hen Harrier and Merlin. Plants Characteristic species include Sheep’s Fescue, Sheep’s Sorrel and Common Bent, Sand Sedge, Wavy Hair Grass, Tormentil, and Heath Bedstraw. Parched acid grassland, in particular, contains a significant number of rare and scarce spring annual plants such as Clustered Clover, Suffocated Clover, Mossy Stonecrop and, in the Breckland area, a number of early flowering plants such as Spring and Breckland Speedwells. Mosses, lichens and fungi The summer-parched soils in Suffolk often support stands of acid grasslands which are rich in mosses (e.g. Polytrichum juniperinum and P. piliferum) and lichens (such as Cladonia spp.). The low nutrient status encourages rare fungi such as Nail fungus Poronia punctata on pony dung and Waxcaps to grow. Invertebrates The tussocky vegetation and bare ground support a wide range of ground-dwelling and burrowing invertebrates such as grasshoppers, solitary wasps and butterflies such as Small Heath and Dingy Skipper. If the habitat is grazed, there may be dung associated species such as fly larvae and dung beetles. FACTORS AFFECTING THIS HABITAT IN SUFFOLK Recreational pressures - some heathland species (e.g. stone curlew) are susceptible to disturbance and are not compatible with public access. Run off from agricultural land - soil and water washed off tillage and outdoor pig fields can contain high levels of nutrients which enrich the heathland, resulting in vegetation changes. Taller vegetation can smother invertebrate colonies such as those of the Silver-studded Blue butterfly. Spray drift is also a problem where there are no buffer zones. Neglect leading to encroachment of pines, birch and bracken. Drainage of wet areas. Inappropriate grazing levels. Although grazing is generally beneficial, over-grazing or under- grazing, and supplementary feeding, can be damaging. A reduction in the rabbit population can lead to under-grazing and so encroachment by trees and scrub, Inappropriate management by golf clubs can lead to a change in the vegetation community through irrigation and additions of fertilisers and lime. Development and change of land use such as road schemes, development at Red Lodge, activities on both redundant and active MOD land and pressure to develop land around Ipswich. Summer fires - this is a particular problem in the heaths around Ipswich. The fires damage Silver- Studded Blue colonies, kill reptiles and destroy the nests and young of ground-nesting birds. Atmospheric deposition of nitrogen contributing to nutrient enrichment and degradation of habitat loss in the Sandlings and Breckland. This issue requires further research. Fragmentation and isolation. For example, only 8% of the once extensive Sandlings heaths remain, ranging in size from 247 ha at Minsmere to fragments of less than 2 ha in Walberswick. 2 HABITAT MANAGEMENT ADVICE Management requirements for individual sites are likely to vary depending on location and type of heath. The points below are general principles only, please use the references for more detail. Maintain structural diversity by including early successional stages, bare ground, short turf and a small amount of scrub. Banks and slopes provide warm conditions for basking and nesting areas for solitary bees and wasps; bare ground benefits reptiles. Areas of taller vegetation are also important and flower-rich areas provide pollen and nectar. Retain natural drainage, including wetland or seepage areas. Maintain light grazing to prevent bracken invasion and keep succession in check. Ensure over- grazing does not occur. If avermectin wormer is used, the animals should be kept off the site for at least 10 days after treatment. Cutting may not be needed as the grassland is very poor and machinery may damage the light soils. If mowing is necessary, maintain a mosaic of cut and uncut patches and remove cuttings. Disturbance may be needed to maintain early successional open habitats. Traditional management in the Brecks has including ploughing and other mechanical disturbance. Use the management history of the site as a guide to current management. Rotational management of gorse and heather can be useful. Rabbits are beneficial on dry grass heath and can be encouraged in order to maintain a short sward. Bracken management may require management with herbicides - see NE TIN048 > Ploughing may be very damaging to heathland soil if this is not part of the traditional management. The potential presence of archaeological features should be checked before work commences. The management of a designated site should not be changed without consultation with Natural England. IMPORTANT ASSOCIATED SPECIES Lunar Yellow Underwing Licinus depressus (Notable BAP species moth snail-eating ground beetle on roadside verges in the Brecks) Gateway to Associated Species > Spanish Catchfly Emperor Moth Examples include: Tower Mustard Green Tiger Beetle Five-banded Tailed Digger Adder Wasp Bur Medick Common Lizard Brush-thighed Seed Eater Breckland Thyme Woodlark Other species Stone-curlew See Notable invertebrates associated with Dry Acid Grassland in Nightjar Suffolk > (pdf) and Buglife Skylark Lowland Heathland > (pdf) Wormwood Moonshiner Green woodpecker Silver Studded Blue Hen Harrier butterfly Merlin 3 Vision for Suffolk 1 Improve knowledge of extent and quality of lowland heathland and dry acid grassland. 2 Maintain the current extent of lowland heathland and dry acid grassland to ensure no net loss. 3 Encourage the restoration and improvement of degraded lowland heathland and dry acid grassland. 4 Re-create lowland heathland and dry acid grassland as opportunities arise. WHERE TO FIND FURTHER INFORMATION JNCC Habitat Description Lowland Dry Acid Grassland > (pdf) JNCC Habitat Description Lowland Heathland > (pdf) Natural England Lowland Dry Acid Grassland Publication 19 > Natural England National Character Area 85 Breckland > Lowland Acid Grassland Creation and Management in Land Regeneration > Forest Research Best Practice Guidelines Publication Note 16.(pdf) Suffolk State of Nature report - Heathland. Compiled by Martin Sanford, Suffolk Biological Records Centre. 2005 > (pdf) Plantlife Important Plant Areas - Breckland > Buglife advice on managing BAP habitats, visit Buglife Lowland Dry Acid Grassland > and Buglife Lowland Heathland > SBP - Notable invertebrates associated with lowland dry acid grassland in Suffolk > (pdf) Buglife Notable invertebrates associated with lowland heathland > (pdf) Plantlife - Threatened Arable Plants ID Guide > (pdf) Bracken management and control - Natural England Technical Information Note TIN048 > (pdf) RSPB- information on land management for woodlark and nightjar, and management of gorse > Suffolk Wildlife Trust Lowland Dry Acid Grassland > and Heathland > MAGIC website > provides interactive mapping information including designations. Making Space for Nature, a Review of England’s Wildlife Sites and Ecological Network 16 Sep 2010. Chaired by Professor Sir John Lawton CBE FRS. Defra website > (pdf) Natural Environment White Paper June 2011 - The Natural Choice: securing the value of nature > (pdf) Contact : Gen Broad, Biodiversity Officer, Suffolk Biodiversity Partnership Tel: 01473 264308, Mobile: 078948 85337, email: [email protected] www.suffolkbiodiversity.org Thank you to SBP partners for contributing to this factsheet 4 .