CHAPTER YII 



MOORLAND ASSOCIATIONS 



General distribution of moorland. Classification of moorland associations. 

 The fen formation. " Hochmoor " and " Flachmoor." Moors and 

 Fens. Bryophytes of the moors. Factors related to the distribution 

 of the moorland associations. Heather moors. Transitional as- 

 sociation of heather moor and siliceous grassland. Bilberry moors. 

 Transitional association of heather moor and bilberry moor. Cotton- 

 grass moors. Transitional association of cotton-grass moor and 

 siliceous grassland. Transitional association of heather moor and 

 cotton-grass moor. Retrogressive moors. The Peak of Derbyshire. 

 Bare peat. Sub-Alpine grassland. Zonation of the moorland and 

 grassland associations. List of species of the moor formation. 



General Distribution of Moorland 



The moorland associations occur on peat whose waters are 

 poor in soluble mineral salts and are also acid in reaction. In this 

 district, the peat is almost wholly confined to the plateaux and 

 to the upper slopes of the sandstones and shales. Peat also 

 occurs in places which the existing geological maps indicate as 

 Carboniferous Limestone ; but most of such localities on exami- 

 nation prove to have a surface layer of chert (figure 1). Certain 

 volcanic and metamorphic rocks of the limestone area also bear 

 moorland plants over limited tracts ; and, as already stated (see 

 pages 122 — 6), heather (Calluna vulgaris) and some of its associ- 

 ates are found on leached limestone soils. There are no lowland 

 peat moors in this district, although they are not rare on the 

 plains both on the east and west of the Pennines. 



The peaty uplands consist of gently sloping plateaux. These 

 are usually dip slopes, or less often the slopes of the valleys 

 of small streams. The peat of the lower plateaux is shallow 



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