CHAPTER XXV 
MOORLAND ASSOCIATIONS 
THROUGHOUT the country the term ‘“‘ moor ”’ is applied 
to almost any stretch of treeless, barren land. It may 
be the wet peat-bogs of the uplands, the heather-clad 
regions of hill-slopes, or the dry heaths of the lowlands. 
The word, although used in apparently so wide a sense, 
is, nevertheless, a good one, for all these areas have some- 
thing in common. They all occur on’soil poor in nutri- 
tive salts, and contain more or less humous acids. Peat 
is present in all cases, varying in thickness from a few 
inches on the dry grass-heath to 30 feet or more on the 
wet cotton-grass bogs. It is the relative abundance of 
peat which determines the character of the vegetation 
of the moorland ; and the amount of peat in turn depends 
upon the character of the underlying rock, the altitude, 
and the amount of water present. 
We saw in Chapter X. that vegetable remains are decom- 
posed by bacteria, and, if the conditions are unfavourable 
for their growth, peat will accumulate. The following 
regions are those unsuited for the work of bacteria, and 
it is in these places that peat is formed and moorland- 
associations develop : 
1. In the lowlands where drainage is very bad, and 
where the water becomes stagnant. This means a lack 
of oxygen in the soil, whilst the evaporation from the 
surface keeps it cold. 
2. At high altitudes where the temperature is low 
for the greater part of the year. If this is combined with 
a very heavy rainfall, bad drainage, and the accumula- 
tion of stagnant water, the conditions for peat-formation 
are intensified. It is under these circumstances that the 
cotton-grass bog reaches its greatest development. 
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