Lowland heath

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1 Lowland Heath
2 Indicator species
3 Ideal heathland structure
4 Threats to heathland
5 Management options
6 UK Lowland Heath
7 References

[edit] Lowland Heath

Is a Biodiversity Action Plan Habitat as it is an ancient wild landscape type. Natural England's Environmental Stewardship scheme describes it as containing dry heath, wet heath and valley mire communities, usually below 250 metres, on acidic soils and shallow peat, typically comprising heathers, gorses, fine grasses, wild flowers and lichens in a complex mosaic. There are usually at least 25% cover of heathers and other dwarf shrubs.

They have acidic, sandy, free draining, shallow soils with a ph of 4-5. There are no worms in the soil, even fungi find it hard to survive. They often have a thick litter layer on top which is difficult to decompose. They are dry in summer and subseptable to drought due to their free- draining nature. In July it is so dry that plants have either shut down or are drought specialists. As many of the plants are waxy, fire is a hazard. A plant animal association has adapted to these harsh conditions.

Lowland Heath can be found in Devon, Hampshire, Dorset (mainly found here), Sussex (some), Kent (some), Surrey (some), Cornwall, Norfolk and Suffolk.

80% of Lowland Heath has been lost since 1800, but the UK still holds a fifth of the worlds stock. Pollen grain carbon dating has indicated that is has existed in the UK for 14000 years. It started to form after this date as the ice-caps retreated. As the weather warmed trees became established and replaced the heathland. But 5000 years ago man began to clear forests and thus the heathland re-established up until the 17th century. From then onwards agricultural and transport technology improved allowing nutrients etc to be put back into the soil,non heathland type crops grown, or it was simply not managed as it had been done in the past.

There are 3 types of heathland according to their location and climate conditions: wet heaths (impervious rocks/clay preventing water drainage), dry heath (well drained), humid heath (between the two types). Wet heaths contain more different species than dry, spagnum moss being an example.

Heathland was originally wooded with richer soil. The woods were removed and the soils eroded and leached, especially nitrogen which leaches away more easily. Therefore heaths are man-made.

Upland Heath which is more than 300 metres in altitude, is called Moorland, Dartmoor being an example.

There is a UK Biodiversity Action Plan has set a target of restoring 58000 hectares of lowland heathland, and recreating a further 6000 hectares.

[edit] Indicator species

Heathers – (Ling) (callum) is dominant on moorland; the flowers are pale purple, the plant branches a lot more, the leaves are in opposite pairs (not whorls); and are oily in order to prevent water loss, they have a symbiotic relationship with fungi. Bell Heather flowers in mid July and is crimson purple and is found on a long spike, its leaves are dark green and less hairy, and they are more turned in so that they can survive on exposed dry sites; they exist as a whorl of 3 leaves. Cross-leaved heather can be found in wetter patches, it has rose pink flowers with a nodding drooping head at the end of the shoot, not as dense a head as bell heather, the leaves are arranged as a cross of 4 are greyish with hairs, and are curled downward – the hairs trap moisture – this plants shut down in summer but grow more in winter. Heathers have a 6 year pioneer phase which is the time they take to form a bush, then it grows until it is 25, when the centre gets more gappy due to the growth becoming less vigorous, mosses/bryophytes start to colonise this area due to the humid conditions. the plant begins to degenerate after 30 years.
Gorse – European (common) flowers in the spring and is found in sheltered locations, Western Gorse is smaller and flowers mid July to mid August on the more exposed areas. Dwarf gorse is found on the Dorset heaths. Gorses are part of the pea family and have nitrogen fixing ability due to their symbiotic association with bacteria.
Bracken – is a fern. Ferns are usually found in wet locations, but this speices can survive in dry locations. Formerly it was cut and used as bedding. Sometimes it was burnt for ash lime, Woodbury common having a fascination history about this.
Grasses – Purple Moor Grass found in wet locations and when young is edible, fescue and bristle bent are found in dry locations
No mammals
Rich in insects

Heathland Succession moves from grasses and bracken, to gorses and heather, and finally to woodland (birch, pine and oaks)

Typical animal species found are:

Snakes and reptiles. The Smooth snake and Sand Lizard are only found in Dorset.
Birds – Dartford warbler, skylark, stonechat, nightjar, hobby (feeds on insects and birds), Tree pipit, wren (feeds on spiders deep in the ground)

[edit] Ideal heathland structure

vegetation various heights and structures
scattered trees
scattered scrub
some bare ground
wet heaths
ponds, water
bogs

cover of dwarf shrubs should be between 25% and 95% with at least 2 species frequent. There must be a range of age classes of heather present, with cover of young heather between 10 to 15%, and cover of old between 10 and 30%. cover of undesirable species (bracken, injurious weeds, invasive non native plants) must be less than 10%. cover of trees/scrub must be less than 15%

[edit] Threats to heathland

Change in farmland in particular afforestation
Fire
Lack of management (overgrown), for example scrub and bracken encroachment
Housing development
Quarrying
Nutrient enrichment
Pine and Silver birch readily establishing and shading the surrounding vegetation
Ploughing

[edit] Management options

Cut trees (e.g. for firewood); using grazing animals to control vegetation and regrowth, control scrub, make sure there is an age range and try to incorporate the requirement of individual species.

Grant is available in England under Natural England's Environmental Stewardship Scheme.

[edit] UK Lowland Heath

East Devon: Gittisham Common, Woodbury Common, Mutter's Moor, Aylesbeare Common, Pebblebed Heaths, Trinity Hill, Venn Ottery Common, Bystock Pools, Fire Beacon Hill, Hartridge Common, Offwell Heath, Hense Moor