To the untrained eye, grass swaying on a North American prairie may as well be grass swaying on an African savanna. To the trained eye, thousands of grass species around the world have distinct differences, and early scientific classification was primarily based on external appearance. But to systematists, contemporary scientists who study the diversification of organisms, exterior clues aren’t good enough anymore.

Seeking to resolve controversial classifications in a specific segment of the grass family, Rancho Santa Ana Botanic Garden (RSABG) Associate Professor of Botany J. Travis Columbus and graduate student Hari Chhetri are undertaking an ambitious project to investigate the grass subfamily Chloridoideae on a molecular level. 

“Historical classifications of Chloridoideae are highly inaccurate and misleading about relationships, thwarting efforts to understand character evolution and biogeography,” said Columbus.

Working with chloridoid grasses collected internationally, propagated at RSABG or borrowed from other botanists, Columbus and Chhetri will examine the plants’ DNA to clarify species relationships and progress toward correct classification. They aim to study 486 species representing all 160 genera within the subfamily, with Chhetri focusing on the tribe Zoysieae, his dissertation subject.

 “Using DNA sequences to assess relationships has proven to be a powerful approach for reconstructing evolutionary relationships and thus improving classifications,” Columbus said. 

Since scientists in a multitude of disciplines worldwide use the same classification system to communicate about biological diversity and make advancements in varied fields, accuracy is essential.

“This will be a very useful reference tool for other fields of biology like horticulture, agriculture, range management, etc.,” Chhetri said.

Improvements made by Columbus and Chhetri will guide applied research – in crop development, for example – which can have significant economic benefits. 

 “Learning what the nearest relatives of economically important species are can lead to improvement of the latter, and the research may reveal species currently not utilized that are good candidates for human use,” said Columbus.

Both Columbus and Chhetri regard RSABG as the premier institution at which to conduct their research, owing mainly to its breadth of facilities and collegial expertise.