Herman Silas Pepoon

Herman Silas Pepoon (1860-1941) was a physician, teacher, botanist, and naturalist with a particular focus on the plants of Illinois and the Midwest. He was born in Warren, Illinois to George and Mary (Abbey) Pepoon. Pepoon married Alma Wilcox in 1883, with whom he had three children: Rudolph Silas, Mary Lucille, and Constance Laura Buckley. After her death in 1893, he married Helen Sophia Foberg in 1900.

Pepoon graduated from the University of Illinois in 1881 and received his medical degree from Hahnemann Medical College in 1883. He spent almost ten years practicing medicine in Lewistown, Illinois, during which time he also served as the Fulton County Fish Warden. Pepoon left the field of medicine and become a teacher and school physician at Lakeview High School (1892- 1930) in Chicago, Illinois and later head of the school’s Department of Botany (1912-1930). After his retirement from teaching, he worked with the Illinois Natural History Survey, helping with the collection and study of vascular plants.

Pepoon was an active and well-known presence in Illinois’ scientific community. He was a Life Member of the Chicago Academy of Sciences, which named him Honorary Curator of Botany for the institution in 1930. The Academy published his best known work, the book An Annotated Flora of the Chicago Area, in 1927. In addition, he published a botanical teaching manual Studies of Plant Life: A Series of Exercises for the Study of Plants (1900) with co-authors Walter R. Mitchell and Fred B. Maxwell. Pepoon also published numerous articles on botany, forestry, and ecology in scientific journals such as “Destruction of a Farm Flora (Plant World, 1903), “Flora of Southwest Michigan (Michigan Academy of Sciences, 1906), and “Cliff Flora of Jo Daviess County, IL” (Michigan Academy of Sciences, 1909). He also served as president of the Chicago Mycological Society (1894-1900) and in a variety of offices at the Illinois State Academy of Science.

During his tenure at Lakeview High School, Pepoon continued to research, collect, and advocate for the preservation of botanical species in Illinois and the U.S. He also dabbled in farming and fruit growing with his brother, William Abbey Pepoon. He spent a considerable amount of time exploring Apple River Canyon, where he identified and collected over 500 species of plants. One of his most noteworthy discoveries in the canyon was Bird’s Eye primrose (Primula mistassinica), a plant previously found only in more northerly locations. Pepoon devoted substantial effort toward the preservation of the Apple River Canyon region, including testifying before the Illinois State Academy of Science (1908) in favor of making it a state park.

Keep Exploring

• Read Studies of Plant Life: A Series of Exercises for the Study of Plants on the Internet Archive.

• Watch Dawn Roberts, director of collections, highlight some of Pepoon’s notes in the collections spotlight webinar below.

• Explore some of Pepoon’s sketches online here. As you examine them, ask yourself these questions:

1. What do you notice on the pages other than just drawings?
2. How did Pepoon incorporate important details and observations?
3. Why do you think he kept a scientific journal like this? 
4. Can you imagine where Pepoon was when he made these observations? What do you think he saw, smelled, and heard?