Nitrogen Fixation as a Stress-Avoidance Strategy Among Actinorhizal (Non-Legume) Trees and Shrubs

Heidi A. Kratsch is Plant Sciences Institute Fellow and William R. Graves is Profes­ sor, Department of Horticulture, Iowa State University, Ames, Iowa, USA.

Address correspondence to: William R. Graves, Department of Horticulture, Iowa State University, Ames, IA 50011-1100 USA (E-mail: graves@iastate.edu).