Rit (Vísindafélag Íslendinga) - 01.06.1975, Page 98
near mountain huts, old outlying sheep cots or deserted farms. It
doesn’t even shy away from the wettest flói tracts where it is usu-
ally small and sparse, however. I believe, however, that it is less
vulnerable to snow cover here than in Norway. In fact, it grows
in snow-patched hollows where it is often one of the main species,
but I believe its proper surroundings are areas where snow does
not accumulate, such as elevated, knolled ridges and Rhacomitrium
heath. But its widest distribution is where the snow covering is
average or just above average. It may be stated that on the whole
it is widely distributed in the highland without regard to snow-
covering, but in the lowland it clearly favours areas where snow
does not accumulate. The same applies to the relationship of C.
Bigelowii to elevation. It extends from sea level upwards unto the
limits of other vegetation. Nothing can be stated concerning its
occurrence in relationship to the acid content of the soil. Nordhagen
(l.c.) is of the opinion that it “foretrekker sur reaktion.” (has a
preference for acid soil) although it belongs to the class of eutroph-
mesotrophic plants, but there is no information to be gained from
its accompanying species in this country. The main character spe-
cies of the C. Bigelowii mýri are the following:
C. Bigelowii: eutroph-mesotrophic
C. rariflora: indifferent
Salix herbacea: reaction to acid content unknown
S. glauca: eutroph-mesotrophic
Equisetum palustre: eutroph-mesotrophic
Vaccinium uliginosum: meso-oligotrophic
The C. Bigelowii mýri is a favoured pasture, especially its drier
tracts. But it seems to me that livestock prefer the grass species and
hicotyledonous plants to the C. Bigelowii itself as the latter tends
to he rather dry for grazing purposes particularly in late summer.
Nothing can be stated as to the stability of this association, but
I helieve it conforms to the general pattern of practically all high-
land associations in being unstable and prone to change in case of
alternations in the moisture content of the soil, or if the area is
subject to erosion.
As may be expected when dealing with an ecologically mistable
species like C. Bigelowii it is hard to define the sociations in which
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