He was a man of deep integrity, modesty, and generosity, who shared his vast experience and knowledge of the plant world with all. As a dean among economic botanists, his work and writing have inspired several generations -- a man who will be personally missed by researchers and small farmers in the Southwest.
After spending his youth as a farmer in Imperial Valley, California, he received a B.A. degree in vertebrate zoology from the University of California, Berkeley, in 1931. He became a free-lance biologist and fossil hunter, collecting specimens in the Sonora, Arizona, Baja, and Nevada deserts from his base at the Carnegie Desert lab in Tucson. He once wrote that environment is the mother of adaptation, and there is a lot mother in the desert, for only the adaptable survive the stress of heat and drought.
In 1942, when Pacific sources of Hevea rubber were obstructed by World War II, Gentry -- at the behest of the USDA -- led a field survey party into Mexico searching for plants which could be grown domestically to produce this critical material, primarily Parthenium (guayule) and Cryptostegia (rubber vine). As a result of his three-year research on the cultivation and harvesting of Cryptostegia, in 1977 he was the choice of the National Academy of Sciences to serve on an advisory panel on guayule.
After the war, he completed his studies for a Ph.D. in botany at the University of Michigan. He then served as research associate at the Allen Hancock Foundation, University of Southern California, Los Angeles. He joined the U. S. Department of Agriculture in 1950 as a research botanist in plant exploration and introduction, conducting eighteen expeditions into Middle Eastern, Balkan, Western European, South African, and Latin American countries as well as the Southwestern United States. His mission was to collect anything of interest to U. S. agriculture. He was deeply involved in studies of agaves as producers of sapogenins, Dioscorea species as a source of steroids, and one yam sapogenin. Gentrogenin, which was named after him. Among other influences he had, Dr. Gentry's articles, published in Economic Botany, encouraged the growth of a number of agricultural industries -- tragacanth (1957), jojoba (1958), and common beans in Mexico (1969).
After retirement from the USDA, Gentry pursued his research in agaves and other desert plants at the Desert Botanical Garden, Phoenix, Arizona, until 1987, supported in part by the National Science Foundation. In 1982, the University of Arizona Press published his Agaves of Continental North America, a definitive 670-page volume on this useful desert plant. His Gentry Experimental Farm, at Murrieta, California, continues his research.
Dr. Gentry is survived by his wife of sixty years, two daughters, and two grandsons.
This article is based on information from an article by Anthony J. Verbiscar in Economic Botany 47 #3 pp. 335-337. (C)1993, by the New York Botanical Garden.
Article copyright American Botanical Council.