Some bee hotels are made from pine, which if untreated, it will entirely rot within a few years, and in general is not a wood species that gives a nice finish. Others choose to use red cedar. While it is rot resistant, it is a softwood that is easily damaged and can look very weathered in a short time. White oak, by comparison, is the longest lasting domestic hardwood for outdoor usage that we have in North America. It's an extremely dense hardwood whose grain is plugged with tyloses to make it water tight, which is why it is often used for ship building, and gives a beautiful finish when treated. It's not easy to work with and it's certainly not cheap, but we think it's worth it. Finally, it has a very low scent, making it less likely to be offensive to bees living in it.