Whereas numerous model now allow to simulate rockfall propagation in forest stands, the mapping of the release areas and associated frequency remains difficult, due to the very low number of observed events. Meanwhile, dendrochronological studies demonstrated that trees impacted by rockfall record information about the spatial distribution of rockfall trajectories. Here we tested, both with simulations and on a real-case study, a framework for the mapping of release areas from observed tree impacts and simulated trajectories. The spatial distribution of tree impacts results from the propagation of rocks from several source cells with different release probabilities. Observations of impacts and simulation of trajectories make it possible to solve the system for the relative release frequencies. With simulated scenarios, we tested the capacity of this method to accurately map the release points depending on their number, distance and width, and on the tree density and diameters. Results show that individual release points can be accurately determined when a sufficient number of rockfall events have occurred. Forest characteristics have only a secondary influence. The method was successfully implemented in a real-case study were 1024 tree were inventoried for rock impacts.