Open-grain hardwoods have pores — tiny tunnels and channels that distribute nutrients to the living wood through capillary action. And nowhere are these pores so open than in red oak. Did you know that you can actually suck up liquids through the pores in a 6" (15 cm) long piece of red oak? Or blow bubbles through it? Author/craftsman Nick Engler has some fun with this amazing and little-known property of oak wood.