Rit (Vísindafélag Íslendinga) - 01.06.1975, Side 109

fiords in the eastern part of the country, hut there it nowhere
achieves the same distribution as in Vestfirðir and in the north.
Nothing can be stated as to its distribution in the northeast, al-
though it is not conspicuous at Melrakkaslétta, which is understand-
able, since it seldom occurs on flat ground.
The Scirpus mire presents a striking appearance; the main
species, Scirpus cæspitosus, grows in tufts, or perhaps the term flat
rnormds might be more precise, but where it is most widely dis-
tributed it may be said to form a continuous vegetation cover and
simultaneously its mound formation disappears. In late summer
the Scirpus mire is pervaded by grey or even yellowish grey hues
which contrast with the dunnish brokflói or the green C. nigra
mire. Eriophorum angustifolium often occurs in the Scirpus mire
as well. The Scirpus is mostly fertile, but as the stalks are rigid
and without leaves the grass in the Scirpus mire tends to he rather
drj- and inflexible. The surface of the Scirpus mire is either mostly
flat or characterised by low, flat mounds so that the vegetation
cover is relatively homogeneous. Moss seldom occurs to any great
extent, although there are often patches of Sphagnmn in the mires
at Snæfellsnes and Mýrar. The terrain is always somewhat slop-
ing, sometimes steeply. Flat strips of Scirpus approximating flói
are exceptions, however. The moisture content of the Scirpus mire
varies considerably. In Reykhólasveit I observed a Scirpus mire
which was almost as damp as flói and the mire at Orrastaðir
(XIV 7) was a similar case. On the other hand I have observed
Scirpus mires in Arnarfjörður which were ahnost as dry as the
grass fields. Predominantly, however, the Scirpus mire has about
average moisture content, or slightly below average. There is al-
ways some peat formation and I believe that Scirpus does not gen-
eraliy occur to any great extent in mires with sandy soil, whether
it be driftsand or volcanic ashes. In short, I would describe the
Scirpus mire in the following terms: It occurs where the climate
is predominantly oceanic and has a heavy snow-cover. The mires
have average moisture content, or slightly below average; they
slope considerably and are characterised by fairly thick peat layers.
In many places the Scirpus mire has been utilized for hay-making
and grazing without any visible lasting effects on its vegetation.
Extensive grazing, however, probably tends to give Scirpus a more
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