RESEARCH IN FOREST GROWTH AND YIELD - BET WEEN CRAVING FOR BETTER UNDERSTANDING AND THE DEMANDS OF PRACTICAL FORESTRY

Questions posed for forest and yield sciences, and methods used to ans wer them are discussed. The main topics of growth and yield during the last decades are referred. While thinning, as the origin of growth an d yield science about 100 years ago, was and is a question addressed b y practical foresters to growth and yield research, forest decline was a problem first discussed in the public and then transferred to fores try and growth and yield research. European growth trends were first f ound by mensurationists and growth and yield scientists and later on v iolently discussed by practical forestry. The methods used in science, forming hypotheses, and establishing experiments to falsify them unde r ever new conditions is a very successful way in the development of o ur civilization but nevertheless persons who think and live in such ca tegories are not quite the people liked in every day life. this might be a reason for the lack of anticipation of the results of growth and yield research in practical forestry. the great success of growth and yield science was its clear concept of using measurement methods and e xperiments instead of former methods of mere verbal description and co mparison to reason about how trees grow. If now site quality seems to change, depending on climate change, pollution, soil acidification and nitrogen deposition and even through forest management our measuremen ts cannot anymore concern age, dbh and tree height only. Thus we will have to either develop growth and yield science towards general forest ecosystem research or at least widen our data sets by links to forest ecosystem models.