To understand complex forest dynamics, long time series of repeated measurements are required as the process of cyclic forest growth can last centuries while having variation at diurnal and annual scales. The lack of methods to characterise tree structure and competition status over time limits our understanding on tree growth allocation and wood formation. Therefore, there is no universally acknowledged theory on how trees allocate and compete for the sunlight, nutrients, and water. The RI consists of detailed measurements from ~10 000 trees growing in varying environmental conditions at the test site of Evo in southern Finland. A 30-year-long time series with annual measurements will be collected using various laser scanning sensors for investigating single tree growth processes, forest dynamics, and forest monitoring technologies. RI is internationally known and serves the R&D needs of the forest industry and of many SMEs operating in the field.