Egbert Hamilton Walker (1899-1991), botanist, was born in Chicago, Illinois. At age two and a half, Walker was diagnosed with polio. His illness, which had been left untreated for so many years, left him with one good arm and a slightly damaged left leg.
After receiving his B.A. degree from the University of Michigan in 1922, he spent four years as an instructor at Canton Christian College (Lingnan University) in Canton, China. In 1926, with the help of Professor Harley Harris Bartlett of the University of Michigan, Walker entered the University of Wisconsin. He received a M.S. degree in botany in 1928 for his paper, Fifty-one common ornamental trees of the Lingnan University campus.
After leaving Wisconsin in 1928, Walker began work in the Division of Plants, United States National Museum at the Smithsonian Institution. Walker spent much of his time reorganizing the neglected, Old World collections and prepared reports on his progress in 1934, 1941, and 1943. Walker became the department's Assistant Curator in 1942 and Associate Curator in 1947. When the Division was reorganized into the Department of Botany in 1947, he was assigned to the Division of Phanerogams.
In 1928, Walker began work with Elmer Drew Merrill to compile a comprehensive bibliography on the literature of Chinese botany. The project was officially recognized as a joint effort between the Smithsonian Institution and the New York Botanical Garden in 1931 when Merrill was Director of the latter institution. The resulting publication was A Bibliography of Eastern Asiatic Botany, published in 1938. A Revision of the Eastern Asiatic Myrsinaceae eventually became Walker's dissertation for which he received his Ph.D. in botany from Johns Hopkins University in 1940.
During World War II, Walker and the staff at the United States National Herbarium became involved in various wartime efforts such as the preparation of survival manuals, pamphlets and articles for the army. Another wartime effort was a Servicemen's Collecting Program, proposed by Harley Harris Bartlett and developed by Walker. As the primary contact for the project, Walker received many plant specimens, primarily from servicemen stationed in Guam, the Aleutian Islands, and Okinawa, Japan.
When the Scientific Investigation of the Ryukyu Islands (SIRI) botanical program was developed by the Pacific Science Board of the National Research Council, Walker was selected to implement the program. In 1951, he left for Okinawa to conduct field work there and the surrounding islands. Walker would make three additional research trips to the area in 1953, 1957, and 1966. This led to the publication of Important Trees of the Ryukyu Islands in 1954 and later, the Flora of Okinawa and the Southern Ryukyu Islands in 1976.
Walker retired from the Smithsonian staff in June 1959 after 30 years. He continued his research on a supplemental edition to A Bibliography of Eastern Asian Botany as a consultant with the American Institute of Biological Sciences in Washington D.C. from 1959 to1960. The supplement, along with the first volume is considered his most important contribution to botany, was eventually published in 1960.
Beginning in 1961, Walker spent the majority of his time writing and revising the Flora of Okinawa and the Southern Ryukyu Islands supported by a grant from the National Science Foundation to the Pacific Science Board of the National Academy of Science. He returned to the Smithsonian staff in 1965 as a Research Associate to the Department of Botany, National Museum of Natural History and continued his work there until 1987.
Walker conducted botanical field work specifically in Okinawa and the Ryukyu Islands, but also in New Zealand, Japan, the Philippine Islands, Hawaii, the Johnston Islands, Guam, Thailand, and Vietnam. He was vice president (1944) and president (1949-1950) of the Botanical Society of Washington and a member of the Botanical Society of Japan.