The career of Dr. Heinz Brücher (1915–1991), a German-Argentine botanist of my personal acquaintance, demonstrates that while science may be impartial, scientists are not. Deconstructing Brücher's ethnobotanical writings has required also reconstructing a Nazi past to put his life and work in their appropriate historical context. Brücher's role in the theft of Vavilov's plant collections in the Ukraine in 1943 and his research on cultivated plants at an SS center in Austria have relevance for understanding his post-war presence and activities in South America. Analysis of his publications in ethnobotany and economic botany, especially as they relate to the potato and to Vavilov's ideas, are placed in the context of his ethnobiography. This retrospective on a life with plants raises issues about political and social ideology in science and about claims to objective knowledge. It also points to the value of broadening ethnobiology to include more reflexive perspectives.