This noxious aquatic weed from South America can clog LA County waterways and flood-control channels, increasing flooding, blocking boat travel, crowding out native riparian vegetation and covering swimming and fishing holes. 

Alligatorweed has been found in LA County since 1956 and areas currently under infestation have restrictions for movement of plant material and soil.  These areas include portions of the San Gabriel and Rio Hondo Rivers as indicated on the following map hold area map.

New hold area alert!

View a video all about the Alligatorweed program.