The Botany of Iceland - 01.12.1930, Side 107

STUDIES ON THK VEGETATION OE ICELAN'D
97
a continuous carpet.” The three species referred to are some of the
most typical plants of the snow patches in Iceland.
The above-cited descriptions of localities in connection with the
llora lists given correspond closely to the geiri vegetation elsewhere,
e. g. on Lýngdalsheiði and Arnarvatnsheiði, and even though Ste-
fánsson does not distinguish tlie geiri or snow patch vegetation
as a separate type, its presence in tlie highland tracts around Vatns-
dalur may be taken for granted. Hence the vegetation here con-
sists of the following four types: melar, mo, mýri, and geiri.
The highland vegetation of East Iceland and Snæfellsnes has
been described in more detail by Helgi Jónsson. In “Vegetationen
paa Snæfelisnes”, where the highland vegetation is dealt wilh, Helgi
Jónsson distinguishes between 3 types, viz. grimmia heath, moun-
tain pools, and fell-field (“Fjeldmark”).
Of the fell-field we find the following statement on p. 27 ff.:
“the fell-field, as taken here, extends over the upper region of the
mountain from the upper limit of the heather moor at c. 300—400 m.
above the sea, to the snow line, with the exception of the mountain
]>ools and the grimmia heath.” “Its surface is very heterogeneous,
consisting now of extensive gravelly or gravelly and clayey llats, now
of more or less downward sloping stretches, bare rocks and screes.
In smaller hollows the subsoil is covered with layers of clay, and
in depressions lakes of greatly varying sizes are met with.”
“The plants of the fell field are scattered here and there, either
in solitary specimens at a considerable distance from each other,
or they are collected in small scattered tufts. Often they occur in
patches, forming a carpet, notably the mosses, Salix herbacea and
Sibbaldia. The scattered plants and the scattered patches of growth
rto not, however, affect the physiognomy of the landscape. Whal
characterises the fell field is principally the stony, gravellj', or
clayey soil.”
“The vegetation of the fell field is very heterogeneous since, as
was pointed out, the soil is very varied. As regards the appearance
°f the vegetation, the factors of decisive importance, besides the
height above the sea, are the greater or less exposure of the locality
and its water supply.”
“The part played by the phanerogams in the composition of the
'egetation grows less and less witli increasing height; at the lower
hmit of the fell field on tlie other hand, they are very abundant.
Here small Empetreta are met witli in patches, Loiseleurieta, Cassi-
Hie Hotany of Iceland. Vol. III. 7