Gatunki drzew obcego pochodzenia na leśnych powierzchniach doświadczalnych Brandenburgii

The history of research on tree species of alien origin began in Germany at the beginning of the nineteenth century, when chancellor Bismarck inspired by information about John Booth – who introduced Douglas fir into Europe – became closely interested in that subject matter (North American trees species were characterised by extraordinary productivity). On 15th June 1880, Bernhard Danckelmann – director of the Forest Academy in Eberswalde – was instructed to work out a detailed scheme of the whole system of forest experimental plots. Adam Schwappach was recruited to Eberswalde in 1886 by Bernhard Danckelmann and was to manage the project. Thanks to that, the forest research institute in Eberswalde has today a one of a kind system of permanent experimental plots including 32 species of alien trees originating mainly from North America (26 species), but also from the Caucasus (1), the Balkans (1) and the Japanese archipelago (4). This paper describes the main objects of research on selected alien species (Pseudotsuga menziesii, Thuja plicata, Chamæcyparis lawsoniana, Chamæcyparis pisifera, Tsuga heterophylla) at the Eberswalde Institute and discusses their most significant results from the point of view of a silviculture-expert. One element of particular importance within this analysis is the comparison of productivity of the researched species in relation to yield tables for Scots pine. Experiments concerning the productivity and usefulness of important tree species of alien origin for different scenarios of climate change (dangerous for the natural environment of Central Europe), have been conducted for over 130 years and the results of those experiments are a further subject of this paper.