Take a journey to see how plant collections can be used to map ecosystem changes over time. Meet Rusty Russell, Botany Collections Manager at the National Museum of Natural History. Rusty manages collections activities in the U.S. National Herbarium, a research collection that contains more than 5 million pressed, dried plant specimens. Visit a part of Southern California that experienced a dramatic shift in plant species composition during the 20th century. See how students and other volunteers can be instrumental in collecting data to tell the story of ecosystem change.