PLANTING OF WATEE CATCHMENT AEEAS 111 



becomes deeper and wetter, especially on the badly drained 

 plateaux, and heather ceases to grow or loses its vigour, 

 becoming thin and stunted. On the wet moors other 

 plants take the place of the heather, the most widely spread 

 being cotton - grass {Eriophorum angustifolium and E. 

 vaginahvm), spike-rush or Scirpus caespitosics, and various 

 species of Sphagnum moss. All these plants grow in deep 

 peat sodden with moisture. The highest wet moors are 

 often the cotton-grass moors, characterised by the growth of 

 one or both species of EriopJiorum, on peat rarely less than 

 5, often 10 to 15 and even 30 feet in depth and saturated 

 with water. Scattered amongst the cotton-grass moors are 

 limited areas of Sphagnum moor, also on very wet peat. 

 Cotton-grass moors are common in the Pennine range on 

 gently sloping plateaux, between 1200 and 2200 feet 

 elevation, and on account of their wetness are locally 

 named mosses. Peat is being formed at a rapid rate in 

 them at the present time. The Scirpus moors are also 

 developed on deep peat, which is still being accumulated, 

 and is saturated with water at most times of the year. 

 The Scirpus is often mixed with a considerable amount of 

 stunted heather. The Scirpus moors are very widely spread 

 in the north of Scotland, the western Highlands, Hebrides, 

 Shetlands, etc., and are common in the Dublin Mountains 

 at lower elevations than the cotton-grass moors. Peat is 

 also being formed at the present day in the Scirpus moors. 



In the southern Uplands of Scotland and the western 

 Highlands, Westmorland and Wales, there are the so-called 

 grass moors, which cover extensive areas of badly drained 

 glacial till and boulder clay. The dominant vegetation 

 consists of moor-grass {Molinia caerulea), mat-grass {Nardiis 

 stricta), and rush (Jiincus squarrosus), growing on a peaty 

 acid soil, which is wet during most of the year. A surface 

 peaty layer, consisting of a sod six to nine inches thick, 

 made up of bases of shoots and rhizomes, rests on an 

 impervious subsoil. The grass moor is not a true moor as 

 the soil is not pure peat. It is much wetter than ordinary 

 hill pasture and has less value for grazing. 



