Publication of "Tropical North American Species of Panicum"

On 24 February 1915, the U.S. Department of Agriculture formally issued Mary Agnes Chase’s monograph "Tropical North American Species of Panicum" as a Bureau of Plant Industry publication.[4][16] This work offered detailed taxonomic treatment of tropical species in the large and complex grass genus Panicum, drawing on her meticulous study of herbarium specimens and field collections from the Americas.

At a time when grasses were poorly understood, especially in tropical ecosystems, the monograph significantly advanced systematic knowledge by clarifying species boundaries, synonymies, and diagnostic characters.[12][16] Chase provided keys, descriptions, and distribution notes that allowed agronomists, ecologists, and other botanists to identify economically and ecologically important grasses. Her analysis contributed to the foundation upon which later revisions of Panicum and related genera were built.

The publication also reflected her growing stature within the USDA and the scientific community, despite lacking formal university degrees.[2][12] As a woman in a male-dominated field, securing a major federal monograph was itself a barrier-breaking accomplishment, demonstrating that rigorous research and illustration skills could overcome institutional bias. Over time, "Tropical North American Species of Panicum" became an essential reference for researchers working in tropical agrostology and helped cement Chase’s reputation as one of the leading grass taxonomists of the twentieth century.[4][12][16]