Logs are basic building materials that have multiple purposes. Logs can be Refined to become Boards, which open up for more complex building opportunities.
Logs are dropped from Evergreens, Mushtrees, Cave Banana Trees and Birchnut trees after cutting the trees with an Axe. The larger the Tree, the more logs are dropped. There are three evergreen tree sizes, which yield 1, 2 or 3 logs depending on what size tree is chopped.
Tree Stumps from cut Evergreens and Mushtrees can be dug using a Shovel to get one extra log. Spiky Trees can also be cut with a chance of getting a log and also give another log when dug up. Mining full Tall Stalagmites also has a rare chance of dropping a log.
Woodie, while in Werebeaver form, can eat Logs to replenish his Log-meter.
In the Reign of Giants DLC, Logs can also drop from Birchnut Trees. A very effective method of harvesting Logs in the DLC is to summon Bigfoot and let it stomp on a group of tightly planted Evergreens or Birchnut Trees.