Greinar (Vísindafélag Íslendinga) - 01.01.1967, Page 55

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ground, but otherwise slopes that descend right to the
cliff’s edge. Dry meadow land dominates on the island
but there is also a substantial area grown with puffin-
colony vegetation on the slopes. Coastal cliff vegetation
occurs only at the above-mentioned landing-place, with
sparse growths of Puccinella and Cochlearia. On the shelf
“Hvannhilla” (Angelica Shelf) there is an area of Ange-
lica cluster.
The flora of Bjarnarey is the richest in plant species
of the outer islands. 30 species of vascular plants have
been found there, five not occurring on other islands:
Anthoxanthum, odoratum, Galium verum, Luzula multi-
flora, Potentilla anserina and Equisetum arvense. These
all grow in a relatively small area of dry meadow land
on the south side of the crater, a place well sheltered
from salt water spray, which might inhibit their distri-
bution elsewhere. On Bjarnarey 8 point-measurements
were taken in all (Table IV). Raunkiaer frequency-mea-
surements were also made for comparison with the results
obtained by B. Johnsen 33 years earlier.
The dominant species of the dry meadow land were
Agrostis tenuis, with about 40% coverage, Festuca rubra
37%, and Poa pratensis 20% on the average. Associated
species covered 3% (Table IV, Bjarnarey 1, 2 and 4).
Agrostis tenuis appeared to increase in frequency with in-
creased distance from the puffin colony, being most abun-
dant where the soil was poorest, which agrees with ob-
servations on Ellidaey.
In Table V the results of the 1966 measurements are
compared with those of B. Johnsen performed in 1933,
showing that there has been little change in the composi-
tion of associations during the period. It appears, how-
ever, that there has been one change in the dry meadow
land inasmuch as Cerastium and Euphrasia have almost
disappeared and been replaced by Anthoxanthum. This
latter species may have been present before, though not
occurring in the 1933 measurements owing to its limited
extent. Stellaria as observed in 1933 is, however, still