Source: California Invasive Plant Council

URL of this page:

Watchlist and Invasive Plant Alerts

Cal-IPC Red Alerts | Other lists

Victorian box
Victorian box tree (Pittosporum undulatum) invades several areas along the central California coast.
Photo by Marcel Rejmanek


Cal-IPC's Watchlist compiles information on plants not yet on our statewide Invasive Plant Inventory that land managers have reported escaping in wildlands. Some of these plants were previously evaluated for our statewide Invasive Plant Inventory but were not added to the Inventory due to lack of information or limited distribution within California. More information will allow us to re-consider these species. For each species, the Watchlist includes where and in what habitat types it has been reported, and where else in the world it is invasive. This watchlist will be updated as we receive new information.

Download Cal-IPC's Watchlist (Excel spreadsheet). Updated June and December. Also see our illustrated watchlist at Calflora.

Please send reports of new species, along with information on the impacts they appear to have and photos if possible, to Elizabeth Brusati, We also encourage entering locations on Calflora. Not only does this provide an initial time frame for the invasion, but also alerts land managers in other regions of the state to the potential threat. Rapid action on a new invader can potentially save millions of dollars with preventative control or even eradication.

"Red Alerts" from the Cal-IPC Symposium

Our annual Symposium includes information on new invasive plants and range expansions. The presentations below (pdfs) contain photographs and details on these species, also listed in our watchlist. Species already included on Cal-IPC's Inventory also have Plant Profiles.

The "Red Alerts" differ from the Alert designation within the Invasive Plant Inventory, which refers to plants with High or Moderate ratings that have the potential to increase their ranges in California.

Other Resources from Cal-IPC

Brachypodium sylvaticum (slender false-brome) - Report sightings of this plant that is spreading in redwood groves of the Santa Cruz Mountains.

The Cal-IPC News occasionally features articles about new invasive plants of concern.

Resources from Other Organizations