Tree-ring analyses have often been used in the past for the reconstruction of spatiotemporal patterns of previous debris-flow activity, often yielding very precise and extensive data for torrents where information on former activity was largely missing. Unless dendrogeomorphology is slated for multimillion Euro developments, the large sets of tree-ring series that are usually used in these studies render analysis time-consuming and not necessarily very cost-effective. In this study, we present results on past debris flows obtained with 35 Larix decidua Mill. trees growing on the cone of the Torrent de Pétérey (Zinal, Valais, Swiss Alps). It is concluded that studies based on a limited number of samples may yield valuable data on past events, but that the reconstructed frequency remains widely incomplete and indications on the spatial aspects of past events are only fragmentary.