Ecological Risk Screening Summary - Giant reed (Arundo donax) - High Risk

Species that are considered high risk have a well-documented history of invasiveness in at least one location globally and are of establishment concern for the contiguous United States based on a climate matching analysis.

Arundo donax, Giant Reed, is a plant native to parts of Asia, although the true native range is uncertain because this species has been widely introduced and utilized since ancient times. This plant is fast growing and is easily able to displace native plant species, including plant
communities that are important habitat for threatened and endangered bird species. Ecosystem alterations from A. donax have been implicated in both wildfires and flooding, which cause economic damage. Although some States regulate possession of A. donax, it is still regularly available in trade, including in the United States. The History of Invasiveness for A. donax is classified as High due to this species being widely established outside of its native range and having documented negative impacts. The climate matching analysis for the contiguous United States indicates establishment concern. Most of the United States had a high climate match, and there were no areas of low match. The Certainty of Assessment for this ERSS is classified as High due to the abundant evidence of established nonnative populations of A. donax and their negative impacts. The Overall Risk Assessment Category for Arundo donax in the contiguous United States is High.