Education
He attended Moline public schools and later Augustana College, graduating with a Bachelor of Arts in 1949, and Iowa State University (Mississippi, 1951, Doctor of Philosophy, 1955).
He attended Moline public schools and later Augustana College, graduating with a Bachelor of Arts in 1949, and Iowa State University (Mississippi, 1951, Doctor of Philosophy, 1955).
After employment with the New Mexico Agricultural Experiment Station (1952–1955) and the Wichita State University (Assistant Professor of Botany, 1955–1957), he joined the Agricultural Research Service, United States Department of Agriculture, with which agency he spent most of his career as a Research Botanist, located on the Texas Agricultural and Mechanical University campus. He retired from this position in 1994 and became Adjunct Professor in Integrative Biology at the University of Texas at Austin. He was also an Honorary Curator at the New York Botanical Garden.
His research interests have centered on the taxonomy of the Neotropical Malvaceae, including work on the evolution, biodiversity, and taxonomy of Gossypium, the genus that includes the world"s cotton crop.
Major publications include The Natural History of the Cotton Tribe (Texas Agricultural and Mechanical University Press, 1979), the Malvaceae of Mexico (Systematic Botany Monographs, 25: 1–522 1988), The American genera of Malvaceae (Brittonia 49: 204–269 1997), and a monograph of the genus Pavonia (Flora Neotropica Monograph 76: 1–284 1999). He was a contributor of treatments of the Malvaceae to numerous Neotropical floristic works and conducted fieldwork in the neotropics, primarily in Mexico but also in parts of Central and South America, as well as in tropical Australia.
He served as president of the American Society of Plant Taxonomists (1983–1984) and of the Society for Economic Botany (1988–1989), held a Fulbright Scholar Award for study in Argentina (1993), was a Fellow of the American Association for the Advancement of Science and of the Texas Academy of Science, and was a member of the Commission of Flora Neotropica.