Should I worry about this wood being from dead trees? Are these products of high quality? What about the emerald ash borer? Is this safe?

It's true that much of the wood currently available from Urbanwood.org is from ash trees killed by the emerald ash borer, but this doesn't diminish the quality or safety of the products. Emerald ash borers live just underneath the bark of infested trees. Once the bark and first layer of wood is removed (a typical part of the milling process), the rest of the wood is completely unaffected. Milled ash wood products are perfectly safe, even under the strict state quarantine requirements (see www.emeraldashborer.info for more information).

Other species of wood, from trees removed for other reasons, are also available. The wood products sold here are always of good quality. In fact, you are likely to find a greater range of species, many with unconventional character and grain, than you are likely to find from most lumber suppliers.