Chinese silvergrass (Miscanthus sinensis) is native to East Asia and South Africa and has been grown as an ornamental in the United States for over 100 years. Chinese silvergrass is on the invasive species list for 12 states in the United States and is regulated for sale in New York state. It is often found along roadsides in middle-Atlantic states and Long Island, NY. In 2019 and 2020, we sowed chinese silvergrass seed harvested in Fall 2002 and Spring 2003 from several locations in North Carolina where it had naturalized and from the Minnesota Landscape Arboretum, Chaska, MN. The seed had been stored in a seed storage vault (4 °C) from 2002 to 2020. Germination in 2003 showed variation between 53% to 95% from 19 different individual plants. This same seed when resown in 2019 and 2020 had much lower germination that could be divided into three categories: no germination (five plants), germination of 1% or less (seven plants), and germination of more than 2% (seven plants). Results from this study show that seed viability may be a long-term problem in locations where chinese silvergrass has naturalized.