The Botany of Iceland - 01.12.1942, Síða 21
THE TARAXACUM-FLORA OF IGELAND
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Often it is also necessary for identification that the fruits of the species
are known. If possible, the best thing is to collect individuals which
have just begun flowering, and likewise specimens with ripe fruits.
Late-flowering individuals, that is, plants flowering later than is normal
for the species, and such as have already shed their fruits are as a
rule very difficult to determine, as often only the inner leaves are left.
The collector should avoid such herbs, unless they have ripe fruits, so
that typical specimens of the species can later be procured by cultiva-
tion. By Reykjahlíð and Laugar in N. Iceland, at the end of July a
Vulgaria-form was collected, which lacked outer and intermediate
Ieaves; at that time they had already withered. The species could not
be determined. However, there were ripe fruits, and by cultivation I
obtained very typical individuals, which could be successfully compared
with other species. Had it not been possiblc to cultivate this species, the
material collected would have been of no value.
Further, conditions are favourable for studies in the field of the
Taraxacum-ilora of Iceland. On account of the mountainous country
the Taraxacum-species can be studied all through the summer, the
height above the sea on the whole determining the flowering season.
In the lowland, for instance in home-fields, the flowering-season, as
mentioned above, sets in at the beginning of the summer on the sides
of the mountains, and later on in the interior of the country, and if
a species is able to grow at various altitudes, its flowering-season will
extend over a long period. In Denmark, on the other hand, where
nearly all the Taraxaca, apart from those growing in the shade, flower
at the same time, the period when the Taraxaca can be successfully
studied in the field is extraordinarily short.
Unfortunately, on my two joumeys in Iceland, I was unable to
study the Taraxacum-ílora. of the great heights. There, I suppose, a
number of unknown species may be met with. The material in herbaria
which I have seen from such places, has not been determinable. In the
future collection of Taraxacum-m'AtcrvA from these territories it will
be necessary, not only to collect flowering plants, but also plants with
ripe fruits, the plants from such places being often small and slender
and not characteristic, so that cultivation may make it possible to gain
a knowledge of this part of the flora and to identify its species.
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