There is a very interesting article on the nation’s first habitat conservation plan, the San Bruno Mountain Habitat Conservation Plan just south of San Francisco. Since the San Bruno Plan is widely looked to for guidance, it is fascinating to read about its status in Fremontia, Journal of the California Native Plant Society magazine (Volume 38:4/39:1). The article is titled, “Managing a Mountain: The San Bruno Mountain Habitat Conservation Plan.”
What is fascinating is that the greatest and most serious challenge the San Bruno Plan Operators face is one of invasive plant species. In a nutshell, coastal scrub vegetation is overtaking native grasslands at a rate of five acres per year, on average. The invasive grasses include rip gut brome (Bromus diandrus), velvetgrass (Holcus lanatus) and herbaceous weeds such as fennel (Foeniculum vulgare), wild radish (Raphanus sativus) and oxalis (Oxalis pes-caprae). The author blames the cessation of grazing and wildfires are the biggest reasons why this is happening.
At the Natomas Basin Conservancy, as our preserves have matured, we too are finding some of the same issues. Maintaining native grass populations has been challenging and expensive. Keeping invasive weeds from taking over preserves has been a never-ending effort. We have had to call on some excellent talent and hard-working experts to help us deal with this. But based on the Fremontia article, it is comforting to know that one of the most prominent habitat conservation plans in the nation has struggled with some of the very same challenges.