Wood postcards have been produced and sold in the U.S. as keepsakes. Wooden postcards were sold for the 1904 St. Louis World's Fair held in Forest Park. Many included puns associated with wood: "Exposition is more than oak-a", "it is ash-tonishing", I wood spruce up and come", "You walnut regret it." and "Butternut delay". The Lewis and Clark Exposition of 1905 and the Jamestown Exposition of 1907 included wooden postcard souvenirs. The tradition of folksy puns continued in later wooden postcard lines. Others feature images, cartoons, advertisements and event commemorations.