This article analyzes private forest owners’ timber supply, taking the social interactions (endogenous and contextual effects) of the forest environment into account. Forest owners’ decisions may vary depending on their observations of their peers’ behavior. Similar timber supply behavior can also be observed when regional characteristics or those of peers are similar. Harvest decision and harvesting intensity are simultaneously evaluated by a selection model that corrects for the endogeneity of the local timber demand. Contextual effects are identified on the basis of the hierarchical nature of the data (individual and regional). Results show, in particular, that forest owners with the same characteristics may behave differently depending on the dynamism of the timber sector and the forest environment.