U.S. Plant Patent 269, for Luther Burbank Rose, Granted to Elizabeth Waters Burbank, February 1, 1938

Natural plant reproduction once seemed beyond human intervention, but in 1930, the U.S. Patent and Trademark Office began recognizing the work of horticulturalists by awarding patents for new or improved plant varieties. Luther Burbank, the prolific American plant breeder, died in 1926, but his life's work helped justify plant patents. Burbank ultimately received 16 patents, awarded posthumously to his widow.