There are two species that are commonly referred to as Old World Bluestem (OWB): Caucasion Bluestem and Yellow Bluestem. With the name Bluestem there is a common misconception that OWB’s are related to native bluestems such as big and Little Bluestem and Broomsedge Bluestem. However, that is not the case. OWB’s are warm-season perennial grasses native to Asia, Africa, and Australia. U.S. introduction took place for conservation purposes and as a forage crop for haying and grazing in the early 1900s. Seedings in Kansas likely occurred between 1930s and 1960s. OWB’s are adapted to high calcareous and high pH soils and do well on any well-drained soil. They are very competitive with native species and are prolific seed producers. Once established, OWB’s increase drastically due to their invasive nature and relatively low palatability.
Identification can be difficult between OWB species without seed heads present. Their vegetative characteristics are rather similar. OWB’s are bunch grasses, but Yellow Bluestem may eventually form a sod with continual heavy defoliation. Grasses will be light green in color during the growing season and a light straw color when dormant. Leaves are thin and pointed, up to 12 inches long, with sporadic long hairs at the base of the leaf. Leaf sheaths are hairless, and ligules are a hairy membrane.
