The Botany of Iceland - 01.12.1942, Page 54

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JOHS. GRONTVED
7. The Li Vegetation.
Mountain-slopes in favourable places, with a southerly exposure,
and a fair supply of water, and shelter from sharp winds develop a
vegetation which is often rather rich in species and luxuriant in growth:
the herb-slope or herb-flat vegetation. This is a type of vegetation which
on the one hand passes into the birch or willow coppice, on the other
hand merges into the rocky flat formation (fell-field or melar vege-
tation. Dicotyledons are generally the most important components,
but in some cases grasses and sedges may dominate (Grass-slope, Grass-
li). The soil is as a rule clayey or gravelly, mixed wih humus (T.T.,
1914, p. 330; H.J., 1895 b, p. 67; 1900, p. 53).
a. Herb-slopes and Herb-flats. The herb-slopes are
found in patches on mountain-sides, on basalt terraces or on
the inclines below rock-walls, in larger ravines and in sheltered
sunny depressions. In the winter the vegetation in these localities
are covered with snow, but in contrast with the snow-patches the
snow-cover will here melt away early in the spring, and the vege-
tative period thus be of a length greatly exceeding that of the snow-
patches. On the most favourably situated south-slopes the herbs may
attain a development scarcely seen in any other formation, and often
a rather large number of species will be found here, intermixed with
each other. The most frequent are:
Geranium sylvaticum
Filiþendula Ulmaria
Archangelica officinalis
Angelica sylvestris
Geum rivale
Rubus saxatilis
Alchemilla vulgaris coll.
Prunella vulgaris
Myosotis arvensis
Galium verum
Gnaphalium norvegicum
Erigeron borealis
Leontodon autumnalis
Hieracium spp.
Rumex Acetosa
Ranunculus acer
Linum catharticum
Coeloglossum viride
Agrostis spp.
Anthoxanthum odoratum
Deschamþsia caesþitosa
Phleum alpinum
Poa spp.
In some parts of Iceland certain characteristic species occur in the
herb-slope vegetation, thus in E. Iceland Campanula rotundifolia and
Saxifraga aizoides, in S. Iceland Valeriana officinalis and Lychnis
Flos-cuculi.
b. Grass-slopes (Grass-li). In the lower part of the
mountain-slopes the vegetation is often composed mainly of grass or