Dear Ernie and all; The Internationjal Code for Names of Cultivated Plants (ICNCP) 7th Ed, 2004 covers this in detail. Get a copy and read it. Best Jim W. -- Dr. James W. Waddick 8871 NW Brostrom Rd. Kansas City Missouri 64152-2711 USA Ph. 816-746-1949 Zone 5 Record low -23F Summer 100F +