Diffuse-Porous Wood vs. Ring-Porous Wood
In some species (e.g. oak and ash), the largest pores are in the earlywood while those in the latewood are more evenly distributed and uniform in size. These woods typically have distinct figures and patterns, and the uneven uptake of stain (the large pores soak up more color) make the figure more pronounced. These are also known as open-grain woods.
In some species (e.g. maple, cherry and yellow poplar) the pores are distributed fairly evenly across the earlywood and latewood. Most domestic diffuse-porous woods have relatively small-diameter pores, but some tropical woods of this type (e.g. mahogany) have rather large pores. These woods usually have even uptake of stain (there seems to be no scientifically proven explanation of the cause of blotching). These are also known as closed-grain woods.