The invasion and expansion of three North American species of goldenrod (Solidago canadensis L sensu lata S. Gigantea Ait. And S. Graminifolia (L ) Salisb ) in Poland

Abstract

I he geographical distributions of three adventive species of North American eoldenrods {.S. canadensis L. S.I.. S. gigantea Ait. and .S. graminifolia (1..) Salisb.) throughout Poland arc presented. The history of escapc. initial establishent and subseauent spread are documented on the basis of almost 1401) herbarium collections and site records of the authors. Of the three species. S. gigantea is the most aggressive S. canadensis has continued to spread vigorously, but S. graminifolia has barely moved beyond its initial area of establishment. The first two species occur essentially throughout Poland, having expanded from centers in southwestern Poland in the dccade between 1840 to 1K50. Both of these plants are spreading rapidly and producing vigorous populations which thrive in disturbed and semi-disturbed environments and .5 gigantea seems to have now attained the capability of invading stabilized habitats and communities. They arc in the process of becoming a serious threat to many natural environments and ecosystems in Poland.