North Somerset Levels

To the south the levels are bounded by the Mendip Hills, to the east by the Yeo Valley and the Lulsgate Plateau, and to the north by the Tickenham Ridge.

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

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 southwest England.

[1] A number of plant species which are otherwise scarce or absent in the Bristol region 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 subsp.

The introduced Canadian and Nuttall's waterweeds are widespread throughout the levels (Myles p.211).