Walter Tennyson Swingle

Walter Tennyson Swingle was an American botanist and plant breeder who spent his career with the United States Department of Agriculture investigating and improving subtropical fruit crops, above all citrus. Born in Pennsylvania and raised in Kansas, he earned his degree from Kansas State Agricultural College in 1890 and joined the USDA the following year, taking charge of its breeding investigations from 1902 and establishing citrus research laboratories in Florida. In 1897, working at Eustis, Florida, he developed the tangelo, a hybrid of the tangerine and the pomelo, and his breeding work also produced the limequat, a hybrid of the lime and the kumquat. Swingle undertook botanical exploration across Mediterranean Europe, North Africa and Asia Minor, through which he introduced date palms and pistachio nuts to American cultivation and imported the fig wasp needed to pollinate Smyrna fig varieties grown in California, and his travels in Asia also brought roughly one hundred thousand Chinese volumes on botany into the collection of the Library of Congress.