adot45, the bottom is open. The boxes are made so that they slide over the tissue box with enough friction that the tissue box doesn't fall out- a design request from the wife.
gdaveg, yes, I love the figure of sycamore. Can't say much for the smell when machining it, though. Maybe that was from some minor spalting, but I haven't experienced any allergic reaction (though I am allergic to molds). That may be because I'm taking a course of steroids for a different issue, though.