That’s been the question since woodworkers darkened oak by burying it in a pile of dung and urine. We have more pleasant choices these days. Stain and dye formulations have been made from ground earth, colored clays, acids, bases, plant extracts, coffee, tea, fruits, berries and, these days, from sophisticated synthesized colorants.
That means we can stain wood whatever color we like. Or not. Admittedly, there are plenty of times I favor leaving wood au naturel. However, there are also times when stain can do a world of good, and make my work greener to boot.