The Botany of Iceland - 01.12.1945, Blaðsíða 147

THE VEGETATION OF CENTRAL ICELAND
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B e 11 2 comprises the following associations:
1) The Carex rariflora—Salix glauca—Carex Goodenoughii-associa-
tion, which is a mixture of flói association 4 and mýri association 6.
2) The Carex rariflora—C. rigida—Salix g/awca-association, which is
closely related to mýri association 3, but is characterised by a greater
moisture.
3) The Salix glauca—Carex Goodenoughii-association, with corre-
sponds to mýri association 6.
4) The Calamagrostis—Salix glauca—Carex rariflora-association,
which is closely related to mýri association 5, though with the dif-
ference that Eriophorum polystcichyum has in part been replaced
by Carex rariflora.
5) The Calamagrostis—Carex rufina-association. This association has
only been found in the flá, but I found very closely related associa-
tions in mýri with sandy soil.
B e 11 3.
1) The Salix—Ccdamagrostis-association. Corresponds entirely to jaðar
association 5.
2) The Salix—Empetrum-association and
3) the Salix herbacea—Cassiope hypnoides-association both belong to
the heath formation, but association 3 has rather the character of
a snow-patch formation, in particular as it occurs near Geldingsá.
Quite probably, also, precisely the edges of the rústs have a pro-
longed snow-covering.
B e 11 4.
The associations in this belt are less sharply delimited than in the
other belts, notably it is often very difficult to decide which species
are especially characteristic in each particular place. Actually we are
here, as in several other places in the flá, concemed with association
fragments or variants. In this belt I have tried to distinguish the fol-
lowing associations:
1) The Elyna Bellardi association.
2) The Elyna Bellardi—Scdix herbacea-association.
3) The Elyna Bellardi—Dryas octopetala—Salix herbacea-association.
These three associations are very closely allied, though association 1
is by far the poorest in chamaephytes. All three associations represent
a kind of intermediate formation between the melur and thc heath
formations. The same applies to:
4) the Armeria vulgaris—Silene acaulis-association, which as regards
species composition and spectra approaches the sandur formation
The Botany of Icland. Vol. III. Part IV.
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