Morphological differences and characteristics of population genetic structure and inter-fertility between Amorpha nitens Boynton and A. fruticosa L. in Illinois

Amorpha fruticosa is common in much of its range. Although Amorpha nitens has a broad distribution, it is poorly known and appears to be scarce in many states within its range. Amorpha nitensis listed as endangered in Illinois (IESPB 2011) and is included on lists of species of special concern, rare plant species, and rare, threatened, or endangered species in Georgia, Louisiana, and Alabama, respectively. Amorpha nitens also is on the list of Regional Forester Sensitive Species for the Shawnee National Forest. There is a need to more closely examine differences between A. nitens and A. fruticosa. This study includes comparison of characteristics of morphology, population genetics, and inter-fertility between the taxa based on populations of both species in southern Illinois.