Minecraft wiki entry for Acacia, associated text: Acacia Leaves (harvested with shears)
Acacia Log (harvested with any tool including hands)
Acacia Planks (created from a log in the inventory crafting grid)
Acacia Sapling (1⁄20 chance of dropping when leaves decay or are broken)
Stripped Acacia Log (created by using an axe on a log)
Stick (chance of dropping when breaking leaves)