Susan K. Pell, Ph.D., former director of science at the Brooklyn Botanic Garden, is the Science and Public Programs Manager at the United States Botanic Garden in Washington, D.C.
Welby R. Smith is the state botanist with the Minnesota Department of Natural Resources in St. Paul. He is the author ofTrees and Shrubs of Minnesotaand a contributor toMinnesotarsquo;s Endangered Flora and Fauna, both published by Minnesota.