Dr. Nilsen was born in Sydney, Australia, the son of a sea captain, and lived for some time in Kobe, Japan, and Oslo, Norway. His early research concentrated on two topics; invasions by foreign plants, and plant responses to stress. It took him to South America, Florida, the chaparral of coastal California, the Sonora Desert of inland California and Baja California in Mexico. His interest in adaptation of plants to environmental stress grew into an interest in rhododendron leaf movements. His talk will be "Patterns and Significance of Winter Leaf Movements in Rhododendron Species".