The Missing Mistletoe and the Non-Purple Great Purple Hairstreak Butterfly

You may not recognize mistletoe unless it sports a red bow and is hanging over a doorway during the holiday season. You may not recognize The Great Purple Hairstreak, Atlides halesus. Its host plant is mistletoe. (Color-cognizant folks who are fond of purple won't recognize it, either. It's not purple! It's iridescent blue!) But what butterfly guru Art Shapiro, a UC Davis distinguished emeritus professor, wants to know is this: "Where is the mistletoe this year?" Shapiro, who has been...