A PRELIMINARY INVESTIGATION OF THE BLUE-EYED GRASSES

Abstract

The genus Sisyrinchium(Iridaceae) is a taxonomically complex group that includes several species that are native to the Eastern United States. Initially, two populations with differing morphologies were observed in areas with contrasting maintenance and mowing regimes. This generated two initial questions: Are these populations the same species, and if so, are the contrasting morphologies due to phenotypic plasticity? Investigations included: surveys for additional populations; whether plants could be transplanted to a common habitat; observation of seedling morphology; simulated mowing to test for plastic responses; germination of seeds; and comparisons of reproductive output and of pigmentation. Results suggest that these populations are the same species but that there are differences in reproductive effort, in pigmentation, and in response to fertilizer application. Further investigations to determine if observed differences are heritable and to characterize the type and extent of genetic differences among populations are planned.