The term 'Lumber Feature' refers to two distinct features of wood: GRAIN and knar. GRAIN is the pattern of fibers in a piece of wood, which can be seen when the wood is cut or sanded. Knar is the presence of knots in the wood, which are caused by branches that have grown into the trunk of the tree. Both GRAIN and knar can affect the strength and appearance of the wood, and are important considerations when selecting lumber for a project.