Germination rate, length, and weight differences in native and nonnative <em>Ratibida pinnata</em> and <em>Sorghastrum nutans</em> seeds

Abstract

An important aspect of tallgrass prairie reconstructions is the origin of the seeds being planted. Our experiment questions whether or not there is a difference in the lengths, weights, and rates of germination in native and non-native Ratibida pinnata (Gray-headed Coneflower) and Sorghastrum nutans (Indiangrass) seeds. We collected samples from the Conard Environmental Research Area (CERA) near Kellogg, Iowa, which we then measured, weighed, and incubated to test their rates of germination. The results showed that the total weight and length of the non-native S. nutans was significantly greater, and the total weight of the non-native R. pinnata was significantly higher, but the mean length and germination rates of the latter were not significant. The significant variations in seed length and total seed weight support conservationists claims that only local seeds should be used in tallgrass prairie reconstruction.