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T. G. Yuncker (1891-1964)

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10.5 linear feet (12 boxes)


T. G. Yuncker (1891-1964) was a taxonomic botanist whose field was the Piperaceae, especially the Peperomia and Piper genera. He described 839 new species, 211 new varieties, and 25 new forma in the Piperaceae. He wrote the treatment of that family in almost every regional flora published during his lifetime. His early studies were on the genus Cuscuta in which he described 67 new species and 39 new varieties.

Yuncker was head of the Department of Botany and Bacteriology at DePauw University from 1923 until his retirement in 1956. Concurrently, he was curator of the DePauw Herbarium from 1919 to 1964. This herbarium was acquired by The New York Botanical Garden in 1987.

Yuncker was a botanical explorer who held the position of Associate Botanist at the Bernice P. Bishop Museum from 1941 to 1964. He was responsible for the first Floras of Niue Island and the Tonga Islands. He also compiled floristic treatments of the Manua Islands, and of large areas of Honduras. His Piperaceae of Brazil was published posthumously.

Truman George Yuncker was born March 20, 1891, on a farm near Carson City, Michigan. When he was 13 the family settled in Lansing. His father became ill and Yuncker had to leave school to support the family, taking up work in the trolley barns. Soon he became a conductor, attending secretarial school at night. In 1907 he entered Michigan Agricultural College (Michigan State University) as an engineering student. After two years he was forced to leave again due to family financial problems. He worked as a secretary for the Durant-Dort Carriage Company in Flint.

It was during this period that he met Ethel Burnett Claflin and became secretly engaged to her. Ethel encouraged Yuncker to return to college and then, in an extremely unusual move for that era, entered Michigan State along with him, delaying marriage until both had graduated. They married in 1915, after Ethel's graduation and a one-year assistantship for Truman at the University of Nebraska under Charles E. Bessey. They moved to Indianapolis where he was teaching at the Emmerich Manual Training High School. In 1916 both Yunckers enrolled at the University of Illinois. Ethel received her M.A. in dietetics and Truman completed his Ph.D. under William Trelease, undertaking a revision of the North American and West Indian species of Cuscuta. Eventually he would take up Trelease's study of the Piperaceae, completing his Piperaceae of Northern South America after Trelease's death.

During World War I the Yunckers moved to Washington, D.C., where Truman served as a bacteriologist with the Army Medical Corps. Ethel worked as a dietician with the Food Administration.

In 1919, the new Ph.D. took up an appointment as Assistant Professor of Botany and Curator of the Herbarium at DePauw University in Greencastle, Indiana. The Yunckers remained in Greencastle for the rest of their lives. By 1921, he had been promoted to full professor and to head of the department in 1924. He became one of the most outstanding teachers and administrators of his generation. More than sixty percent of his students went on to earn advanced degrees.

The Yunckers began their botanical explorations in 1926 with an extended trip to European herbaria for a world survey of Cuscuta. In 1932 Yuncker was awarded a Yale-Bishop Museum fellowship for a one-year sabbatical at the Bernice P. Bishop Museum. Ethel Yuncker took over his duties as department head, teaching some courses as well. At the height of the Depression, she made it possible for Yuncker to devote himself to his studies without undue economic hardship to the family. In 1939, the whole family went to Hawaii for the summer. Truman went on to Niue and Samoa for fieldwork on his floras of those places. He was forced to use military transport in this sensitive area, soon to become a front in World War II. Other explorations were a survey of the Tonga Islands in 1953-1954, the study of the flora of Jamaica through a Fullbright and a study of Brazilian Piperaceae, 1957-1962, under a National Science Foundation grant. Yuncker studied not only the flora but the activities of the people of those places and recorded his observations in his correspondence and notes.

Following the death of William Trelease in 1946, he was invited to the University of Illinois to complete Trelease's unfinished work on the Piperaceae of Northern South America. This involved a complete revision and editing of Trelease's notes. All 675 photographs in the work were taken and prepared by Yuncker. The work has become a classic.

Yuncker's last major work, The Piperaceae of Brazil (1972-1975), was completed with the help of Ethel Claflin Yuncker and published and distributed to the scientific community by her. Her work on it was recognized in many quarters from the Bishop Museum to the Smithsonian Institution.

Both Ethel and Truman were active in Greencastle civic life for their entire lives. Ethel held office in the Daughters of the American Revolution on a state level and was national president of Phi Omega Pi. She often went by her maiden name. Truman served for years as the honorary forester of Greencastle. He was active in the Kiwanis Club. Both Yunckers belonged to the Freemasons.

Yuncker officially retired from DePauw in 1956. He became emeritus and remained curator of the herbarium until his death in 1964. At that time it was renamed the T.G. Yuncker Herbarium by its new curator, Winona Welch. In 1987, as Welch's ability to care for it became compromised, the Herbarium was sold by DePauw to The New York Botanical Garden. Separate Brittonia festschrifts, edited by Dr. Patricia K. Holmgren, were prepared in Yuncker's and Welch's honor.

In 1966, 2 years after Truman's death, Ethel moved to Asbury Towers, a retirement community she had helped to plan. Her apartment was on the same floor as Dr. Welch's. In Dr. Yuncker's memory, she donated a solarium, whose plaque reads "Scientist and Teacher, Jungles and the South Seas were his workrooms, DePauw and Greencastle his home."


The Truman G. Yuncker Papers (1919-1989) document Dr. Yuncker's taxonomic studies on Cuscuta and Piperaceae, especially his work on William Trelease's Piperaceae of Northern South America and his life as an educator at DePauw University. One series contains materials from Brittonia 41(3), 1989, a volume dedicated to him as a Festschrift. Material from many locations was photocopied for this volume and remains here with the papers. The Ethel Burnett Claflin Yuncker Papers, photocopies of a biographic scrapbook spanning three generations, provides information on small-town family life in the first half of the twentieth century. It contains correspondence, photocopies, notes, diaries, manuscripts, drawings, maps, clippings, bound material, glass negatives, lantern slides, photographs, microfilm, an audio tape, a field collection bag, and one field collector's notebook. The collection is arranged into 14 series.


Series 1: Biographical Information, 1936-1968
Series 2: Festschrift, 1987-1989
Series 3: DePauw Archives, 1919-1989
Series 4: Ethel Burnett Claflin Yuncker Papers, 1943-1981
Series 5: Correspondence,1938-1964
Series 6: Expeditions, 1932-1953
Series 7: Manuscripts and Publications, 1972
Series 8: Cuscuta, 1921-1957
Series 9: William Trelease Papers, 1928-1936
Series 10: Geographic Files, [ca. 1920-1950]
Series 11: Species Files, [ca. 1920-1950]
Series 12: Illustrations
Series 13: Photographs and Lantern Slides
Series 14: Negatives

Series 1     Biographical Information, 1936-1968
                    1.5 lin. in. Arranged by subject.

This series contains a biographical sketch of Truman Yuncker and photocopies of material from the DePauw Archives related to Yuncker's life. Other biographical materials are found in Series 4: Ethel Burnett Claflin Yuncker Papers. Biographical photographs are found in Series 13: Photographs and Lantern Slides.

Series 2     Festschrift, 1987-1989
                    5.5 lin. in. Arranged by subject.

This series contains materials assembled for the issue of Brittonia dedicated to Truman Yuncker. It includes photocopies from the DePauw and Smithsonian Institution Archives, a microfilm from the Gray Herbarium, correspondence from Yuncker's students and colleagues, and material related to the publication of the volume. Photographs and plates from the Festschrift are found in Series 13: Photographs & Lantern Slides.

Series 3     DePauw Archives, 1919-1989
                    4.5 lin. in. Arranged by subject.

This series contains photocopies of materials housed in the DePauw University Archives that are related to Truman Yuncker's career as an educator and his to civic life in Greencastle. Other material on these subjects is located in Series 1: Biographical Information and Series 4: Ethel Burnett Claflin Yuncker Papers. Photographs documenting Yuncker's career are found in Series 13: Photographs and Lantern Slides.

Series 4     Ethel Burnett Claflin Yuncker Papers, 1943-1981
                    3 lin. in. Arranged by subject.

This series contains a photocopy of a pictorial biography, a scrapbook assembled by Ethel Yuncker over the course of the Yunckers' life together, and her life after Truman Yuncker's death. Correspondence in this series is original and relates to Ethel Yuncker's distribution of her husband's last book to the scientific community.

Series 5     Correspondence, 1938-1964
                    2 lin. in. Arranged alphabetically.

This series contains original correspondence culled from the Truman G. Yuncker Herbarium as it was processed and incorporated into the New York Botanical Garden's Herbarium. Material relates to determinations, exchanges, and disposition of duplicate materials.

Series 6     Expeditions, 1932-1953
                    1 lin. in. Arranged chronologically.

This series contains photocopies of personal and scientific correspondence, clippings, memorabilia, a diary, and a field notebook. Dr. Yuncker's plant collection bag is found here. Other material related to Dr. Yuncker's expeditions is found in Series 3: DePauw Archives and Series 4: Ethel Burnett Claflin Yuncker Papers. The field notebook has been removed and is located in the Field Collectors' Notebook collection.

Series 7     Manuscripts and Publications, 1972
                    2.5 lin. in. Arranged chronologically

This series contains photocopies of some of Yuncker's reprints, promotional material, manuscripts, and typewritten notes. Other manuscript material is found in Series 9: William Trelease Papers, Series 10: Geographic Files, and Series 11: Species Files.

Series 8     Cuscuta, 1921-1957
                    1 lin. in. Arranged by subject.

Cuscuta was the first genus studied by Yuncker. This series contains some early notes, reprints, correspondence, and manuscripts.

Series 9     William Trelease Papers, 1928-1936
                    5 lin. in. Arranged by subject.

This series holds manuscripts and correspondence for Trelease's unpublished North American Flora monographs on Peperomia and Piperaceae. Other material by William Trelease is found in Series 10: Geographic Files and Series 11: Species Files.

Series 10     Geographic Files
                    1.5 lin. ft. Arranged by subject.

These files contain bound notes by William Trelease and Truman Yuncker on Peperomia and Piperaceae arranged geographically.

Series 11     Species Files
                    4.75 lin. ft. Arranged by subject.

This series contains bound notes by William Trelease and Truman Yuncker on Peperomia and Piperaceae arranged by species.

Series 12     Illustrations
                    3 lin. in. Arranged by subject.

This series contains line drawings of Piperaceae related to Yuncker's research, and 3 herbarium sheets with line drawings. Slides of some of the drawings are also included in this series.

Series 13     Photographs and Lantern Slides
                    4 lin. in. Arranged by subject.

This series contains photo plates and unused material from the Festschrift volume. Other photographs are found in Series 10:  Geographic Files and Series 11: Species Files.

Series 14     Negatives
                    1 folder, 2 glass plates. Arranged by subject.

This series holds the negatives of the photographs used for the Festschrift volume. The glass plates are of 2 unidentified fungi.


The New York Botanical Garden

PP     The Winona H. Welch Papers

Bishop Museum Archives

The Truman Yuncker Papers, 1943

DePauw University Archives

The Winona H. Welch Collection

The Truman G. Yuncker Collection

Processed March 2000 by Laura Zelasnic under a grant from the National Endowment for the Humanities (NEH) PA-23141-98 and a grant from the Harriet Ford Dickenson Foundation.

For more information and a complete description contact:
Susan Fraser, NYBG Archivist
The LuEsther T. Mertz Library
The New York Botanical Garden
Bronx, NY 10458-5126
(718) 817-8879

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