At Harvard Forest in Petersham, visitors can learn about the forest and its history through dioramas dating back to the 1930s. The dioramas and the museum that was built for them was the idea of Richard T. Fisher, who was named director and primary professor when Harvard decided to create a forestry school in Petersham. … “The dioramas took 10 years to build with seven people working full-time,” Hart continued. “The reason it took so long is that each tree and branch was created with one wire, then they would continue to coil [the wire] over one branch to get a thickness. It was built the way trees grow, thicker and thicker. The first seven dioramas are a historical series with the same composite landscape, changing from 1700 to the 1930s and showing how landscapes changed. Originally called The Harvard Forest Models, the dioramas were unveiled in 1937 for Harvard’s tercentenary in Cambridge.