In this subproject we will focus on species interactions and growth on a tree to tree level. We will examine the crown structure of neighboring trees of the same or unequal species and study the efficiency of tree growth. The structural crown parameters like crown base and branchiness are also of importance to estimate assortments and to derive tree value and wood quality. All results will be integrated into a forest growth modeling software. A single tree growth model will be used to design and evaluate mixed species stand treatment by computer simulation and to develop silviculture guidelines for the field application.