Greinar (Vísindafélag Íslendinga) - 01.01.1967, Qupperneq 3

THE
IMMIGRATION AND NATURALIZA-
TION OF FLOWERING PLANTS
IN ICELAND SINCE 1900
By
INGÓLFUR DAVlÐSSON
Abstract.
The present paper describes the immigration and naturalization
of foreign species of flowering plants in Iceland in the present cen-
tury. Foreign plants have never before been introduced, accidentally
or deliberately, to the extent they have been in the present century,
especially since the beginning of World War II. Since the turn of
the century 183 species of foreign plants have been found growing
in a wild state in Iceland, not including those foreign species that
had become permanently established before 1900. Of these 183 spe-
cies, 26 may now be considered as well established. These are almost
all perennial species. Most of the remainder are of irregular occur-
rence, not surviving for any length of time in any one place. The
foreign species still grow almost entirely in or near towns and farms,
while in the uninhabited areas the native vegetation holds it own. But
on the other hand many of the most common plants around towns
and farms are of foreign origin.
The majority of those foreign species that are not deliberately
introduced for cultivation are carried to Iceland with grass seed and
chicken fodder.
The paper lists foreign species recorded from selected localities
in all parts of Iceland, and the detailed history of the immigration
and spread of 7 foreign species is given as far as is possible.
Introduction.
When the first settlers came to Iceland about 1100 years
ago the vegetation was more continuous and penetrated
further up into the highlands than it does now. Birch
i