the branch of botany concerned with the study of grasses (grass), especially their classification. In 1708 the German botanist Johann Scheuchzer wrote Agrostographiae Helveticae Prodromus, a taxonomic paper on grasses that some authors consider to mark the birth of agrostology. Many systems of classification followed this brief beginning. The earliest were based purely on external morphology of the plant, but later systems take into consideration the results of cellular, embryological, physiological, and histological studies.

Modern agrostologists investigate living populations of grasses to determine their genetic inheritance and adaptations to specific habitats. Biochemical studies are another promising tool in determining evolutionary relationships between groups of grasses.