This work focuses on qualifying the influence of the different crown elements on the me-chanical behavior of tree submitted to time varying loading. For this purpose, dynamic tests were performed on three Pinus Pinaster Ait. seedlings. The aerial architecture of the trees was digitized. Crown spatial pattern varied significantly between the seedlings. In order to identify their intrinsic dynamic characteristics, the seedlings were submitted to free sway tests under different loading cases. The natural swaying frequencies that were measured did allow an assessment of the turbulent scale each structure is sensitive to. Anisotropy in trees’ ability to dissipate energy absorbed from initial loading was observed. The tests also showed evidence that a secondary swaying mode was activated under specific loading. A couple of experimental subjects were tested at different phases of a progressive pruning with the pur-pose to weight participation of architectural elements in the dynamics of structures. Results showed that the needles had a critical role in damping process. Experimental data was suffi-cient to feed a numerical model and to proceed to further analyses on the influence of branching pattern in the mechanical tree stability.