New A-Rated Weed Detected in Oregon

The Oregon Department of Agriculture (ODA) has confirmed A-rated Hydrilla verticillata on private property in Jackson County, marking its first detection in Oregon. The ODA enforces a quarantine against specific noxious weeds to prevent their introduction and spread. As an A-rated species, hydrilla requires a high-priority response. If established, it could significantly threaten Oregon’s aquatic resources and irrigation infrastructure. 

Hydrilla verticillata is an invasive aquatic plant native to Asia, Africa, and Australia. It is considered one of the most problematic invasive plants in the United States and worldwide. H. verticillata is listed on both the Oregon Noxious Weed List and the USDA Federal Noxious Weed List. While it is the only species in its genus, specialists have identified several morphological variations. The plant was introduced through the aquarium trade and subsequently released into waterways. It is now widespread across the United States, from Connecticut to Florida, throughout the central states, west to Texas, and along the Pacific coast. 

ODA is working closely with the land owner to assess the extent of the Hydrilla verticillata and to develop restoration plans. The agency will provide updates as more information becomes available.  

ODA will also educate land managers and the public on hydrilla identification and the steps to take if it is suspected. For more information, contact the ODA Noxious Weed Control Program at 503-983-4065. 

Please report suspected invasive species through the Oregon Invasive Species Hotline online portal and include clear photographs.