The naturalist program at Indiana State Parks evolved from an early program established at Bear Mountain State Park in New York state. A visiting dentist from Illinois, inspired by the program at Turkey Run State Park in 1936, helped develop the fledgling nature museum program. Indianapolis artist Lucy Pitschler in began taking park guests on nature hikes in  the 1920's, which led to the development of the naturalist program in the state parks. The contributions of these, and many others, has led to the wonderful naturalist programs that park guests enjoy at most of the Indiana State Parks today. 
From the book:
McCormick's Creek State Park
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