North Somerset Levels

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The North Somerset Levels from Dolebury Warren

The North Somerset Levels are the northern section of the broader Somerset Levels, separated from the wider expanse of the Levels by the Mendip Hills. They form a flat, coastal plain, and expanse of land which is largely at sea level.

The North Somerset Levels may be found in ihe north of Somerset between Weston-super-Mare and Bristol.

The three principal rivers draining this part of the Levels are the River Banwell, River Kenn, the Congresbury Yeo and the Land Yeo. As across all of the Somerset Levels though, the landscape is cut through with innumerable streams and drainage ditches ('rhynes') and its rivers have been straightened and diverted to serve the purpose of draining the land, creating rich farmland from what was once a feverish marsh.

To the south, the North levels are bounded by the Mendip Hills. To the east is the Yeo Valley and the Lulsgate Plateau, and to the north by the Tickenham Ridge. To the west lies the Severn Estuary.

The water level management and maintenance of rhynes in the area are the responsibility of the North Somerset Drainage Board.

Towns and villages on the North Somerset Levels

The following are the principal towns and villages in the area

Wildlife and conservation

A number of areas of the Levels have been designated as 'Sites of Special Scientific Interest':

  • Tickenham, Nailsea and Kenn Moors SSSI is an extensive site in the northern part of the Levels.
  • Yanal Bog, a calcicolous mire near Sandford is designated for its plant communities, within which grow Black Bog-rush (Schoenus nigricans) and Blunt-flowered Rush (Juncus subnodulosus), two plant species rare in the south-western counties.[1]

A number of plant species which are otherwise scarce or absent in Somerset are found in high concentrations on the North Somerset Levels, including Water Horsetail (Equisetum fluviatile),[2] Rigid (Ceratophyllum demersum) and Soft (C. submersum) hornworts,[3] Thread-leaved (Ranunculus trichophyllus), Common (R. aquatilis) and Fan-leaved (R. circinatus) water-crowfoots,[4] Lesser Water-parsnip (Berula erecta),[5] Tubular (Oenanthe fistulosa) and Fine-leaved (O. aquatica) water-dropworts,[6] Tufted Forget-me-not (Myosotis laxa ssp. caespitosa),[7] Skullcap (Scutellaria}[8] and Fen Bedstraw.[9] Water-violet (Hottonia palustris) is found here, mainly in the Nailsea & Tickenham areas, but also in scattered locations further south; this species is found nowhere else in the Bristol region.[10] Water fern Azolla filiculoides has been introduced and has become widespread throughout.[11]

Other plant species which are otherwise scarce or absent beyond the levels but found in high concentrations on the North Somerset Levels are: Flowering-rush (Myles, p. 210), Lesser Water-plantain (Myles, p.210-1), Frogbit (Myles, p. 210-1), Lesser Pondweed (Myles, p.212-3), Small Pondweed (Myles, p. 212-3), Hairlike Pondweed (Myles, p213), Opposite-leaved Pondweed (Myles, p.213) and Horned Pondweed (Myles, p.213).

Canadian and Nuttall's Waterweeds, plants introduced here, are now widespread throughout the levels (Myles p.211).

Outside links

References

  1. SSSI listing and designation for Yanal Bog
  2. Myles (2000), pages 56-7
  3. Myles (2000), page 63
  4. Myles (2000), pages 67-8
  5. Myles (2000), page 159
  6. Myles (2000), pages 160-1
  7. Myles (2000), pages 170-1
  8. Myles (2000), pages 174-5
  9. Myles (2000), page 190
  10. Myles (2000), page 109
  11. Myles (2000), page 60