Ben Cao Jing Jizhu (Variorum of Shen Nong's Herbal, compiled in 536 AD by Tao Hongjing of the Northern and Southern Dynasties period) mentions a poisonous rhododendron, saying that when goats eat its leaves they wander about and die.
石楠、杜鵑，理還亂！南北朝陶弘景撰集的《本草經集注》提到有毒的杜鵑花說：羊食其葉，躑躅而死。因此杜鵑又稱「躑躅」。