Harold Emery Moore, Jr. was an American botanist especially known for his work on the systematics of the palm family. He served as Director of the L. H. Bailey Hortorium at Cornell University, and was appointed Liberty Hyde Bailey Professor of Botany in 1978. He was an important contributor to Hortus Third and was founding editor of the palm journal Principes. He also edited Gentes Herbarum and provided the foundation for the first edition of Genera Palmarum, a seminal work on palm taxonomy which was later completed by Natalie Uhl and John Dransfield.
Moore was born in Massachusetts in 1917. He received his B.S. from Massachusetts State College in 1939. He then moved to Harvard University where he obtained his M.S. in 1940 and Ph.D. in 1942. After graduating, he served in the United States Army from 1942 to 1946. In 1947 he joined the staff of the Gray Herbarium at Harvard. In 1948 he moved to the L. H. Bailey Hortorium at Cornell as an Assistant Professor of Botany. He was appointed Associate Professor in 1951 and full Professor in 1960. Between 1960 and 1969 he served as director of the herbarium, and was elected Bailey Professor of Botany in 1978.