German botanist (agrostologist) working in the USA. Isa Degener and her husband, Otto, spent many years in association with the New York Botanical Garden and the pair worked together for most of their lives studying the flora of Hawaii. Born Isa Hansen she studied at the University of Berlin and began to work as there an assistant to Drs. H.O. Sleumer and E. Werdermann. Later based at Berlin Botanical Garden she specialised in the grasses and by 1952, when Otto Degener came to Berlin in search of a grass expert, he began a correspondence with Isa whom he would later marry. The pair focused on the flora of Hawaii and with her help, often as co-author, Otto Degener would publish 10 books and over 400 journal articles on that topic. Of greatest importance is the couple's New Illustrated Flora of the Hawaiian Islands or Flora Hawaiiensis which appeared in seven volumes between 1933 and 1957.

In 1975 Isa Degener was named Honorary Collector of Hawaiian Botany. The Degeners were also keen promoters of wildlife conservation in Hawaii and in 1979 the state senator issued a resolution of recommendation honouring their outstanding efforts in this field. As well as Hawaii, they also made an important expedition to Polynesia. The majority of their herbarium material is housed at the New York Botanical Garden (NY).

Sources:
Anon, 1988, Taxon, 37(2): 509
H.H. Bartlett, 1957, "Otto Degener: Botanist of the South Seas", Asa Gray Bulletin, 3(2): 197-198
Otto Degener Records (1920-1987), Archives and Manuscript Collections, The New York Botanical Garden:
http://sciweb.nybg.org/science2/libr/finding_guide/degener3.asp, accessed 11 May 2011.