
California Invasive Species Action Week began Saturday, June 5 and runs through Sunday, June 13, 2021. Increasing public awareness of invasive species and their impacts helps protect our natural resources, waterways, native species, agriculture, and health.
UC IPM has several resources on exotic and invasive species as well as information on specific pests both present in California as well as pests that have a high...
- Author: Elaine Lander

Brooms are shrubs which were originally planted in California as ornamentals and for erosion control, but are now considered to be invasive weeds since they are highly competitive. They crowd out native plants and form impenetrable barriers to wildlife. There are four common species of broom in California: Scotch broom, French broom, Spanish broom and Portuguese broom.
In the newly revised Pest Notes: Brooms, UCCE advisor Scott Oneto and UC Davis weed scientists Joe DiTomaso and Guy Kyser explain the issues with planting these invasive species. The publication includes expanded sections on biology and management and updated herbicide...

(Credit: S Ausmus)
Stink bugs are common pests in gardens but the brown marmorated stink bug, or BMSB, is of particular concern. BMSB (Halyomorpha halys) was first detected in Los Angeles County in 2006 and has since been detected in many other parts of California with large populations in some counties.
What does BMSB look like?
The adult BMSB is similar in shape to other stink bugs can be distinguished by the following characteristics:
- Two white bands on the antennae
- Forward edge of head is blunt
- Margin of the shoulder is smooth
- Legs are marbled brown with faint white bands
- Membranous parts of...

In California, P. ramorum is primarily a leaf pathogen and thrives in coastal tanoak/redwood forests and oak woodlands. There are two categories of hosts for P. ramorum....

(Credit: ME Rogers)
Invasive species are non-native plants, animals, or pathogens that can cause economic or environmental harm. This year, we will be spotlighting several different invasive species that are established in California to raise awareness and help reduce their spread. Stay tuned—we will be showcasing a different invasive species each day and where you can find more information.
Want to learn more about California Invasive Species Action Week? Check out the full schedule of...