Making these up.

Logs:

• Take more than 1 hand to pick up

• Burns for more than 30mins

• Can cause concussion if thrown through the air.

First it must become a branch, then work its way up to being a limb, and through perseverence and bravery, it may one day be a trunk. Trunks make great logs.

When you can’t wrap your hand fully around it, I’d say, is the boundary between a stick and a log.

If you can stand on it and roll it with your feets, that’s a log. Can’t do that with a stick. Nobody ever heard of the stick rolling championships.

When a dog cannot carry it

Stick is a branch where as log is part of the trunk. Narrow trunk is called a sapling.