Rit (Vísindafélag Íslendinga) - 01.06.1975, Síða 157
97. Deschampsia cæspitosa — Anthoxantlium odoratum sociation
(Tab. XXn A-B 7-8)
Only two analyses exist from this jaðar, both made on narrow
strips, 3-5 metres in width, on the border of mýri and heath. The
analyses differ in such a way that each has its own character spe-
cies. A common characteristic, however, is that gramineous plants
are dominant in hoth and there is close affinity with the Equisetum
jaðar, since E. palustre occurs to a noticeable extent. The sociation
is not widely distributed, although it occurs throughout the country.
On the other hand there is the Calamagrostis jaðar which only
occurs in the highland. It could be divided into two sociations,
depending on the occurrence of Salix glauca, but I believe, however,
that it is more correctly fused into one sociation.
98. Calamagrostis neglecta — Salix glauca sociation
This sociation is described in my paper 1945. It occurs either as
a distinct jaðar belt between mýri tract and shrub heath, or as a
strip between mýri and sand. In the latter case it is certainly a
pioneer sociation. (cf. Steindórsson 1945 pp. 406-407).
e. Shrub-jaðar
Along with the Juncus jaðar and the Equisetum jaðar there is
the shrub jaðar, the third main jaðar division, where the shruhs
Vaccinium uhginosum, Empetrum and Betula nana becomes do-
winant species in physiognomy and often in covering as well. They
all belong to heath vegetation. Carex Bigelowii which also occurs
there can be both a mýri and heath plant, Eriophorum angusti-
folium and Carex nigra, on the other hand, are pure flói and mýri
species. This jaðar type most commonly occurs in the belt, which has
frequently been referred to, between mýri tracts and heath, but it
is also encountered on mound-ridges and hróf within flói or mýri
areas. It occurs more commonly between flói and heath than be-
tween mýri and heath; thus it was adjacent to flói tracts every-
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