Found some fun pics of bikes made of wood in the Phillipines, Africa, and other locales.... A couple samples:
Notice the foot-activated brake for the rear wheel...
And here is the Recumbent Bicycle Enthusiasts club of North Phillipines (RBENP)
Of course, it raises the whole "steel is real" issue -- what tree is the best for bicycle building, Coconut Tree, Mango Tree, Kawayan or Bamboo, Narra, Mahogany, Ipil-Ipil, or Molave??? Mahogany is Marvelous, Bamboo is Boss...