This publication is largely based on growth-site studies carried out on important tree species in Dutch forests during the period 1950-1991. Two of the ways the data yielded by these studies can be used were investigated. The first aimed to identify important correlations between growth and site properties. The second used combinations of site properties in an attempt to predict site index; this is important for the proper choice of tree species, or if previously unforested land is to be afforested (but only if the site properties do not change intrinsically in response to changes in environmental conditions).The investigations centred on the Dutch forest as it has evolved since the mid- nineteenth century. The pioneer tree species was Scots pine, later partly replaced by other species. Chapter 1 presents a short description of the history of heathland afforestation and examines the background of growth-site research. In Chapter 2 a description is given of the character of growth-site research and the methods commonly applied. A critical discussion of methods and interpretation is included.Growth-site research in Northern America and in northwestern Europe is discussed in Chapter 3, in relation to the methods applied and relevance for the interpretation of relationships established for forest stands in the Netherlands. Attention is paid to the international literature on the study of growth-site relationships. Forestry in the Netherlands is distinctive, because it is a rather young type of land use, which occupies a small area and was until recently mainly restricted to poor soils. The range of meteorological variables in the Netherlands is small, and therefore the interpretation of results of growth-site studies must rely partly on studies in neighbouring countries. This chapter also describes the history of growth-site research from the nineteenth century to the present.Chapter 4 gives a comprehensive description of the field and laboratory methodology applied in Dutch growth-site research from 1950-1991. This ...