The most significant threat to the plant and animal diversity and ecosystem function of San Bruno Mountain’s unique habitats is the invasion and expansion of invasive non-native plant species. Key to controlling the invasion of these introduced species will be to identify and eliminate new populations of aggressive invasive plants before they take hold of an intact native area and expand to unmanageable numbers.

We will accomplish this by a weed patrol program to find new populations of invasives that can still be easily removed, with ongoing follow-up work that will guarantee control.   Also, where large populations have already become established, holding the line and maintaining control of the leading edge will be paramount to stem the loss of more areas. When larger restoration project funding is available, we will remove and fully restore areas currently dominated by invasive species.

Invasive species that are the primary focus:
French, Scotch, and striated brooms
various non-native thistles
poison hemlock
Himalayan blackberry
English and Cape ivy
pincushion flower
velvet grass
Ehrharta grass