Otto and Isa Degener records
Scope and Contents
CONTENT WARNING: The Fritz Kuhle file includes government seals with swastikas, as well as references to racial purity and imprisonment in Berlin during World War II. Additionally, other parts of the collection – particularly Series 1 – contain outdated and derogatory language used to describe Asian and Pacific Islander communities.
The Otto and Isa Degener records consist of correspondence, research materials, subject files, personal papers, and photographs documenting the personal and professional lives of Dr. Otto Degener and Dr. Isa Degener. The bulk of the material spans from Otto Degener’s student years at the Massachusetts Agricultural College (now the University of Massachusetts Amherst) in the late 1910s to his death in January 1988.
The collection highlights Drs. Otto and Isa Degener’s research on Hawaiian flora, as well as their conservation efforts to protect Hawaii’s endemic plant species. Additionally, the records reflect their professional relationships with several major botanical institutions, including the New York Botanical Garden, the Bishop Museum, the Berlin Botanical Garden, and the Hunt Institute for Botanical Documentation.
Although the Degeners collaborated closely for over three decades, much of the material in the collection – particularly the outgoing correspondence – was created by Dr. Otto Degener. Many letters are addressed to both Otto and Isa, but the correspondence is largely written from Otto’s perspective. The personal papers primarily belong to Dr. Isa Degener and were organized and labeled by her. Information related to Isa after Otto’s death is limited, with the exception of a 2014 fire that resulted in the complete destruction of her home.
Dates
- 1899 - 2000
- Majority of material found within 1940 - 1987
Creator
- Degener, Otto, 1899-1988 (Person)
Conditions Governing Access
This collection is open for research by appointment.
Conditions Governing Use
Requests for permission to publish material from the collection should be submitted in writing to the LuEsther T. Mertz Library of the New York Botanical Garden.
Biographical / Historical
Otto Degener (1899–1988) was a systematic botanist and conservationist best known as a leading authority on the flora of the Hawaiian Islands. He earned his M.S. from the University of Hawaii in 1923 and his Ph.D. from Columbia University, where he studied under Nathaniel Lord Britton, Per Axel Rydberg, and Robert Almer Harper. Moving to Hawaii in 1922, he taught botany at the University of Hawaii from 1925 to 1927, and in 1929 was appointed the first naturalist for Hawaii National Park. He was appointed Collaborator in Hawaiian Botany by the NYBG in 1935 and was associated with the NYBG until his death.
Irmgard (Isa) Hansen (1924-2018) was a taxonomic botanist who specialized in agrostology and pharmacognosy. She began her career as a botanical assistant at the Berlin Botanical Garden and earned her doctorate in 1949 at the University of Berlin under Dr. Hermann Sleumer. To finance her education, she worked as a lecturer and research assistant to Drs. Robert Pilger and Hermann Sleumer at Humboldt University. After completing her studies, she worked at the Freie Universität Berlin, where she taught pharmacognosy to pharmacy and medical students.
On a trip to Berlin in 1952 seeking to consult a grass specialist, Dr. Otto Degener met Dr. Isa Hansen, and the two began a correspondence that led to their marriage in January 1953. Together they traveled the world, collected specimens, and studied the flora of the Hawaiian Islands, which resulted in 10 books and over 400 journal articles, including later volumes of the New Illustrated Flora of the Hawaiian Islands (Flora Hawaiiensis) – the first comprehensive flora of Hawaii since William Hillebrand’s 1888 publication.
Over the course of their careers, the Degeners collected more than 36,000 different plant species and preserved some 900 threatened and endangered plants. Otto Degener was awarded the Linnaeus Medal by the Royal Swedish Academy of Sciences in 1962 and the Willdenow Medal from the Berlin Botanic Garden in 1979. Isa Degener was named an Honorary Collaborator of Hawaiian Botany at NYBG in 1975. In 1979, both Degeners received NYBG’s Distinguished Service Award and were jointly honored by the Senate of the State of Hawaii for their conservation efforts.
Otto Degener died on January 16, 1988, in Honolulu, Hawaii. Isa Degener passed away thirty years later, on April 13, 2018, in Waipahu, Hawaii.
Extent
14.8 Linear Feet (34 document boxes, 1 card file box, and 1 lantern slide box)
Language of Materials
English
German
Arrangement
The collection is organized into six series:
- Series 1: Correspondence, 1919-1992, bulk: 1960-1987
- Series 2: Subject Files, 1917-1991, bulk: 1960-1987
- Series 3: Research Papers, 1923-1988, bulk: 1940-1986
- Series 4: Personal Papers, 1899-2000, bulk: 1944-1988
- Series 5: Topping File Card Index, undated
- Series 6: Lantern Slides, 1946
Other Finding Aids
Please note that the legacy finding guide is outdated and may contain incorrect information.
Legacy EAD finding guide
Immediate Source of Acquisition
The Otto and Isa Degener records were transferred to the New York Botanical Garden archives in ten separate accessions, occurring in 1979, 1980, 1986, 2010, 2021, and 2025.
Existence and Location of Copies
In 1968, Dr. Otto Degener began depositing his papers with the Hunt Institute for Botanical Documentation, starting with his earliest correspondence from 1915. Beginning in 1973, he sent all subsequent materials to the New York Botanical Garden Archives instead. Both depository agreements included the provision that Xerox copies of the correspondence were sent back to the Degeners, while the originals were retained by each institution. As a result, this collection contains a complete set of papers, supplemented by the early Hunt Institute Xeroxes from Dr. Otto Degener.
General
There are no Degener field notebooks in the collections of the NYBG.
Processing Information
The collection was reprocessed in 2025, primarily to incorporate an accrual received by the NYBG Archives in 2021. During this process, the collection was rearranged to include the new material, which resulted in the creation of the “Research Papers” and “Personal Papers” series, as well as the retitling of the collection from the “Otto Degener records” to the “Otto and Isa Degener records.” Newspaper clippings were photocopied and discarded.
- Bernice Pauahi Bishop Museum
- Booksellers and bookselling
- Botanischer Garten und Museum (Berlin, Germany)
- Botanists’ spouses
- Correspondence
- Deer -- Control -- Hawaii
- Endemic plants -- Hawaii
- Environmental protection -- Citizen participation
- Hunt Botanical Library
- Introduced organisms -- Hawaii
- Landlord and tenant -- Hawaii
- Lantern slides
- New York Botanical Garden
- Personal papers
- Photographs
- Plant Conservation -- Hawaii
- Plant collecting
- Publishers and publishing
- University of Hawaii (System)
- World War, 1939-1945
Creator
- Degener, Otto, 1899-1988 (Person)
- Degener, Isa (Person)
- Topping, David LeRoy, 1861-1939 (Person)
- Title
- Otto and Isa Degener records
- Status
- Completed
- Author
- Stephen Sinon in 1999 with further revisions by Nicole Font in 2025.
- Date
- December 1999
- Description rules
- Describing Archives: A Content Standard
- Language of description
- English
- Script of description
- Latin
- Sponsor
- Originally processed by Stephen Sinon, Assistant Archivist, December 1999. Converted to EAD in October 2006 by Kathleene Konkle under a grant from the National Endowment for the Humanities (NEH-PA 50678-04). Reprocessed by Nicole Font, Shelby White and Leon Levy Processing Archivist, in July 2025 with funding from the Leon Levy Foundation.
Revision Statements
- October 2006: Converted to EAD by Kathleene Konkle.
- July 2025: Reprocessed by Nicole Font
Repository Details
Part of the The Archives of the New York Botanical Garden Repository
New York Botanical Garden, Mertz Library
2900 Southern Boulevard
Bronx NY 10458 United States
archives@nybg.org