Click here for photos and a slide show of the French broom removal work party by volunteers at Miller-Knox Regional Shoreline Park in Pt. Richmond on Saturday, March 31. At least 32 people (of all ages, shapes, and stamina) joined staff from the East Bay Regional Park District to remove hundreds of mature (and highly invasive) Broom plants. In doing so, breathing room was created for 20+ Oaks, a Toyon, and a Redwood that were cowering under the weight and intensity of the Broom.

Jane and Tom Kelly (janek@migcom.com) note that “The volunteer energy was so strong and pervasive that we had a hard time getting people to take a break. Our little friend Max, who pulled the raffle tickets, told Jane (rather impatiently) that he didn't have time to draw tickets because he had “to get back to work”!  That’s the spirit! Everyone who came to the work party surprisingly won something at the raffle causing one volunteer to claim that the raffle was “rigged”. It was … as there were actually even more prizes (native plants) than volunteers.”

Special thanks to Nancy and Kevin from the EBRPD for their support and quiet supervision. It was great to have Nancy there to tag the native oaks and answer our questions about the park and the local biology. Finally, kudos to Bruce Bayaert of TRAC, who looped out the work party announcement that brought a number of awesome volunteers from Richmond.

Why is it so important to control the growth of Broom in Richmond’s open spaces and parklands? French broom currently occupies approximately 100,000 acres in California. It displaces native plant and forage species, and makes reforestation difficult. It is a strong competitor and can dominate a plant community, forming dense monospecific stands. In an experiment in New Zealand French broom had a higher growth rate than any other broom species found in California, reaching an average height of more than 4.5 feet (141 cm) in two growing seasons. Since it can grow more rapidly than most trees used in forestry, it shades out tree seedlings in areas that are revegetated after harvest.

French broom foliage and seeds are toxic, containing a variety of quinolizidine alkaloids, especially in young leaves (Montlor et al. 1990). In some livestock, ingestion of plant parts can cause staggering followed by paralysis (McClintock 1985). Foliage can cause digestive disorders in horses (Parsons 1992). Infestations of broom degrade the quality of habitat for wildlife by displacing native forage species and changing microclimate conditions at soil levels. French broom is believed to be responsible for reducing arthropod populations by one-third in Golden Gate National Recreation Area. It burns readily and carries fire to the tree canopy layer, increasing both the frequency and intensity of fires. French broom along roadsides obstructs views, requiring expensive ongoing road maintenance. This species establishes a dense, long-lived seedbank, making it difficult to eradicate.

Possibly the largest infestations of French Broom in Richmond occur on the Chevron Refinery property, where they continue to expand and act as a seedbank to carry the invasive species to other property, including parklands. Harboring French Broom is a violation of the Richmond Municipal Code, and although the City of Richmond has given notice to Chevron to clean up its out of control Broom growths, the corporation appears to have told Richmond where it can shove its broom handle. Unfortunately, Richmond appears not to have the stomach to take on Chevron in a mano a mano Broom battle. You would think a company that engages in something as flammable and explosive as refining petroleum would be concerned about limiting the spread of fire on its property. Guess not.