On the phytosociological position of two immigrant plants from South America to Northwest Germany

Abstract

The author deals with two notable cases of invasion of South American plants in Northwest plant associations German and the phytosociological position of both invaders.

As a companion of relatively low degree of authenticity, Mimulus guttatus (= luteus) is found in some places in the Filipenduleto-Geranietum of the German Northwest, which, according to the species that compose it and their ecological behavior, is compared with the riverine associations, in which is indigenous this plant. Even stronger is the sociological position of Galinsoga parviflora, which occurs in the German Northwest as a characteristic species of the Panico-Chenopodietum polyspermi (BraunBlanquet) and the Panico-Chenopodieltum polyspermi stachyetosum palustris (Tiixen) but also as a character species of the order Chenopodietalia Middle Europe (Tiixen) as for example in the Sperguleto-Chrysanthemetum segetiranunculelosum repens (Tüxen). Thus, by the invasion of suitable plant forms, notable successions in the plant associations of territories with widely stable vegetation can be produced, which are close in importance to the modifications that can occur when the existing vegetation is eliminated to allocate the land to culture.

Finally, from the discussion of the conditions of dissemination and conservation of plants in strange associations, he draws conclusions about the ?social habit? of the plant.