Rit (Vísindafélag Íslendinga) - 01.06.1975, Page 67

hagen 1927, p. 427), seems closely related to this association, since
they occur under similar conditions. However, the C. rariflora as-
sociation in Iceland does not appear to have any preference for areas
where the snow cover is thick.
34. The Carex rariflora sociation
(Tab. VI A-B 14-18 and Tab. VI y A-B 8-9)
Observations of this sociation are all from the central highland
with the exception of one, VI y 8 is from Snæfellsnes, since the
sociation is much more common in the highland than in the low-
land. The species are relatively few and none is significantly notice-
ahle there except C. rariflora alone. E. angustifolium is fairly con-
stant but always prostrate. Calamagrostis neglecta, Polygonum
Wviparum and Salix glauca are fairly frequent, of which the last
!s the only one which may be considered characteristic of the
sociation.
A group is in a clear majority as may he excepted in view of
the sites of occurrence. Ch percentage is fairly high due to the
frequency of Salix glauca and Salix herbacea, both of which, hut
Salix glauca in particular, have great amplitude vis á vis moisture
content in the soil.
Analysis VI. 14 is from Gilsárstekkur in Breiðdalur E-Icel. at an
altitude of approx. 400 metres ahove sea level. When the observation
was carried out in the last days of July the area was dry, but
otherwise it was evident that in spring and during rainy spells
there would be a muddy flói. Moss was considerable. The socia-
hon there covered a rather large area. Analysis 15-16 from Kýl-
mgar and no. 17 from Síðumannaafréttur are all made under simi-
lar topographic conditions. The sociation occurs there in little pat-
ohes in the Eriophormn flói under varying moisture conditions,
but everywhere rather wet. Analysis 18 is from Holtavörðuheiði
where Salix glauca and Equisetum palustre are so noticeable, that
perhaps it would be proper to refer to it as an independent socia-
hon. Analysis Vly 8 is the only lowland observation from Gerðu-
berg in Snæfellsnes. C. chordorrhiza occurs there in considerable
abundance in tufts or beds within sociation. Analysis VI y 9 is
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