The Botany of Iceland - 01.12.1930, Page 99
STUDIES ON THE VEGETATION OF ICELAND
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Thalictrum alpinum. Of minor importance are Festuca oviua, F. rnbra,
Cardamine pratensis, and Empetrum nigrum.
Wliere the ground-water covers the soil throughout the year
the knolls disappear, the surface is level, and the llói vegetation is
formed (cf. table 20,7). The dominant species are Eriophorum poly-
stachgum and Carex chordorrhiza.
D. NORÐTUNGA.
In the preceding part we liave dealt with all the lowland types
of vegetation except tlie l'orest. In the following I shall give a
description of it in so far as I was able to examine it during a
couple of days’ stajr on tlie farm Norðtunga in Borgarfjörður.
Here the forest occurs botli at the bottom of the valley and on
the sunny northern slope, but not on the shady soutliern slope.
The succeeding investigations, however, apply especially to the forest
at the bottom of the valley.
Viewed from one of the valley slopes the l'orest does not appear
as a continuous growth in the sense that the trees are equally di-
stributed over the entire area of growth, but open patches where
the birch is low, very scattered, or entirely absent, alternate with
stretches where the growth is denser. It was, however, especially
on the outskirts that this was the case, in the interior of the forest
the growth was continuous.
Fig. 14 shows a glade in the forest. The soil is full of large
knolls.
The statistical results are given in table 21 A. Nos. 1—2 are
from tlie forest itself, 3—6 l'rom the glades in the forest, No. 7,
finally, is the mo some distance outside the forest between the latter
and the farm.
On the forest-ground proper grasses are dominant, the following
being the most numerous: Deschampsia flexuosa, Anthoxanthum
odoratum, Agrostis canina and A tenuis, furtlier Fesluca rubra; of
herbaceous plants there occur Thalictrum atpinum, Carex rigida,
Gatium boreale and Normanni, and Polggonum viviparum. The
chamaephytes are of minor importance, Vaccinium uliginosum and
Empetrum nigrnm are found here and there.
The vegetation of the glades occupies an intermediate po-
sition between the forest-ground and the mo. The species known
from the forest-ground recur liere, moreover a number of typical