 Charles C. Deam, a botanist who in 1909 became Indiana's state forester, was in charge of making the state forest an experimental laboratory for 20th-century forest care.Between the opening of the forest, and 1935, over 150 different tree types were tested, many of which survive yet.During the Great Depression, the Works Progress Administration chose to make Clark State Forest a training center for the Civilian Conservation Corps, and also made it Indiana's largest CCC cantonment in November 1933.