Rit (Vísindafélag Íslendinga) - 01.06.1975, Page 130

76. V. uliginosum — Eriophorum angustifolium sociation
(Tab. XVIA-B 6-7)
This sociation is closely akin to the preceding one (75). The oc-
currence of B. nana and Empetrum, however, is greatly reduced
here whereas E. angustifolium has increased in quantity and C.
nigra has largely disappeared. Otherwise the topography is similar,
but this sociation, however, grows in even damper soil than 75 and
has a closer affinity to flói.
Both the analyses were made on mound pattemed strips, inter-
spersed with C. chordorrhiza — flói at Mýrar where the sociation
is widely distributed. Moss is abundant.
I have described the same sociation at Melrakkaslétta where I
referred to it as an Eriophorum angustifolium — Vaccinium uligi-
nosum association (Steindórsson 1936 p. 449).
It is widely distributed there in an environment resembling
Mýrar, but the species are generally more numerous and B. nana
occurs, but E. angustifolium is more conspicuous. The sociation is
closely allied with sociation 12 (Tab. IV 1-5) and it could be a
moot point whether it should rather be classified as belonging to
the mýri or the flói as has been mentioned earlier. At Krossanes
in Vatnsnes this sociation is widely distributed in mire-borders and
various mire strips — towards the centre of the area a C. nigra —-
C. chordorrhiza sociation occurred. The Vaccinium strip varied in
width; it was relatively dry with Rhacomitrium on the mounds.
Apart from the character species the following occurred: Equisetum
palustre, Anthoxanthum odoratirm, Festuca rubra, Galium pumi-
lum, Luzula multiflora, Polygonum viviparum, Salix glauca, S.
herbacea, Thalictrum alpinum. On the whole I would consider this
sociation to be the closest relation of the Scandinavian rismyr so-
ciations.
77. Betula nana — Carex nigra sociation
B. nana often becomes dominant in the shrub, but V. uliginosum
mostly disappears although this sociation is closely related to the
V. uliginosum sociations. I have observed this sociation at Hlaðir
in Hörgárdalur where it is common on both slopes of Moldhauga-
háls. There it occurs in fairly extensive mire tracts and is in no
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