What is porous wood and what are its characteristics?

Porous wood is wood that contains vessels (characteristic of angiosperms/hardwoods) with relatively large diameters, creating a porous appearance when viewed in cross-section. Porous wood is further classified into ring-porous wood and diffuse-porous wood. Ring-porous wood (found in oak, ash, and elm) has large vessels concentrated in the early wood, forming distinct rings, while diffuse-porous wood (found in maple, birch, and poplar) has vessels of relatively uniform size distributed fairly evenly throughout the growth ring. The porosity affects the wood's properties: ring-porous woods often have distinct grain patterns and varying densities across growth rings, while diffuse-porous woods tend to be more uniform. This classification helps in wood identification and predicting wood properties for various commercial uses.