Ivan and Robertha Arneson of Canby, Oregon were schoolteachers who had a farm—which gradually filled with a variety of brightly colored Mollis and Exbury azaleas. In 1959 they began a breeding program to develop better bright, clear-colored flowers. They worked largely with the Mollis and Exbury hybrids and seedlings, working to produce brilliant reds and other intensely-colored blooms. By the 1980s they were developing 100 crosses per year and selling 20,000 plants. With the advent of tissue culture they worked with Bruce Briggs to bring some of their crosses into production. Read their article from JARS for more details and a list of hybrids as of 1995: Ivan and Robertha Arneson, JARS v29n1 - Hybridizing for Superior and Unique Azaleas