Using a combination of NMR and mass spectroscopic techniques, we have isolated a new salicinoid from the foliage of European aspen (Populus tremula) and identified it as 2'-(Z)-cinnamoylsalicortin. The relatively high amounts in foliage and the similarity in structure to bioactive salicinoids isolated from other salicaceous trees indicates that this compound may have implications for the study of P. tremulaherbivore interactions.