Folke Karl Skoog was a Swedish-born American plant physiologist who was a pioneer in the field of plant growth regulators, particularly cytokinins. Skoog was a recipient of the National Medal of Science. He was Born on July 15, 1908 in Halland, Sweden, Skoog emigrated to the United States during a trip to California in 1925, and was naturalized as a citizen almost a decade later. He competed, and finished sixth in heat 2, in the 1500 meter race during the 1932 Summer Olympics. In 1936, he received his PhD in biology from Caltech for his work done with auxin, a plant hormone. He died on February 15, 2001 in Madison, Wisconsin, United States.