This is a close-up of one of the lattice panels. The Cedar is "kiln-dried" to 13% moisture content. This is the relative humidity in the majority of North America.

This dry lumber is used so it will not shrink which would cause joints to open or loosen. Baldwin's joints start out tight and stay tight with or without maintanence. This is a perfect mid-lap joint. Tightbond Outdoor Wood Glue is used in these joints eliminating the need for fasteners.