Tree trunks are important building materials. They are obtained by felling fully-grown trees, and each tree gives 1 tree trunk. In order to do so, an axe must be used, with a woodsman's axe being the best at this. They may sometimes be found on the ground. To use a tree trunk for constructions, it must first be converted into logs with the timbercraft skill. The timbercraft skill can also be used to turn tree trunks into boards or blocks of wood.
Weighting 520 lbs, tree trunks are far too heavy for even the strongest character to pick up. The best method of transporting them is to move a tree trunk onto the same tile as a raft or punt, then rafting out onto water.