Giant Cane, Arundinaria gigantea, is the only native woody grass found in Illinois. It was once widespread in canebreaks in southern Illinois, but has since declined in abundance due to habitat alteration. Giant Cane can often be found in colonies, since it spreads through rhizomes. The easiest way to identify it is to look for its stems since they look like bamboo.
If you are in a natural area where ornamental bamboo has not been planted, it's likely that you found Giant Cane. Looking at the leaves, they can be very broad with rounded bases or more linear. They are usually a darker, glossy green. You can find two collections of a few long hairs at the top of the leaf sheath. Giant Cane will flower once in its life and then die, and its lifespan is typically one to two decades.
This video is part of the Grasses at a Glance series by Natural Resources, Environment, and Energy Educator Erin Garrett, University of Illinois Extension. Explore the playlist. Read our blog Grasses at a Glance.