Frank Hagen1, Thomas Smith1, Dr. Elly P. H. Best1, and Dr. Jeffrey Dawson2. (1) Engineer Research and Development Center, U.S. Army Corps of Engineers, Champaign, IL 61826, (2) Department of Natural Resources and Environmental Sciences, University of Illinois, Urbana, IL 61801
Military ranges are subject to exposure from munitions energetics, the long term environmental consequences of which are not well understood. As part of larger efforts, the U.S. Department of Defense is involved in studies to identify ways to minimize environmental effects of military activities. We report on initial results of ongoing research to identify rapidly colonizing, and resilient forb species tolerant towards range-relevant contaminates, with emphasis on RDX and TNT. A literature review was conducted to identify forb species with characteristics that make them potential candidates for use on ranges for phytostabilization and phytoextraction purposes. Five criteria were used based on which plant species were selected for inclusion in short-term screening experiments for tolerance towards RDX and TNT. These criteria were: tolerance towards energetics, resilience-related life cycle characteristics and plant traits, typical biogeographic distribution, seed size, and availability of propagules. A total of 55 species were reviewed, of which 8 were selected for further study. Short-term screening experiments for tolerance towards TNT and RDX were conducted, following standard testing procedures. Dose-response experiments formed the basis for the evaluation of toxic effects. In these tests seeds were exposed for 12 to 21 days and germination was determined. Of the 8 species screened, 5 exhibited a medium to good germination capacity. None of the well-germinating forbs were significantly inhibited by RDX. Two species were stimulated by a high RDX concentration of >1000 mg kg-1 soil. Based on the results of this effort, 5 forbs were identified as rapidly colonizing, and short-term tolerant towards TNT- and RDX- contamination of soils.