Functional–structural plant models (FSPMs) allow simulation of tree crown development as the sum of modular (e.g. shoot-level) responses triggered by the local environmental conditions. The actual process of space filling by the crowns can be studied. Although the FSPM simulations are at organ scale, the data for their validation have usually been at more aggregated levels (whole-crown or whole-tree). Measurements made by terrestrial laser scanning (TLS) that have been segmented into elementary units (internodes) offer a phenotyping tool to validate the FSPM predictions at levels comparable with their detail. Sievänen et al. demonstrate the testing of different formulations of crown development of Scots pine trees in the LIGNUM model using segmented TLS data.
They test different formulations of crown development. Shoot elongation was best controlled by a combination of local and branch level light availability and production of new buds by local density. Their method shows a great potential for further and more comprehensive studies of tree crown development by combining modelling and laser scanner data.