High Quality Content by WIKIPEDIA articles! Rudolph Gustav Hass was the developer of the Hass avocado, the source of 95% of avocados grown commercially today. Rudolph Gustav Hass was born in Milwaukee, Wisconsin on June 5, 1892 to Henry C. Hass and Alma F. (Zergman) Hass. Known as Rudie, Hass quit school after finishing 10th grade at age 15 and went to work. He tried to enlist in the Army during World War I, but they rejected him due to a congenital heart murmur. Rudie met Elizabeth Schuette on 7/4/1918 at a 4th of July church picnic. He was involved in a mission work with children on weekends and asked Elizabeth if she could play the piano for his ministry at the mission. She agreed and thus their courtship began. They were married about a year later on 8/2/1919 in Milwaukee, Wisconsin. The family moved to Pasadena, California in 1923.