The basic resource in Timberborn - at least the demo - is, naturally, the log. Beavers are somewhat naturally equipped for the task, so the logging post is only there for directing specific beavers to the task. And yes, buildings employ specific, named citizens for the task. Also, your populace is split into rapidly growing children and almost as rapidly aging adults, so there will be a natural ebb and flow to the workforce.
Such is the tragedy of enhanced beaver metabolism.
