By Eva Buxton, Conservation Chair Marin Chapter CNPS

Tiburon Middle Ridge composed of serpentine grassland and outcrops is the most biologically and ecologically valuable of the Town of Tiburon’s preserves (26 parcels in all).  RareSpeciesTiburon hired consulting firm LSA Associates, Inc. to update the Open Space Resource Management Plan (OSRMP) which I co-authored for that same firm in 2010.   Although I am retired, I had the opportunity to accompany the authors of the plan update on a field visit to the Middle Ridge (MR) parcel and give input into the new plan.  The updated plan, the Short-term Implementation Plan (STIP), is being reviewed by Tiburon’s Parks, Open Space & Trails Commission. After review, comments, and possible revision it will eventually be adopted by the Tiburon Town Council.

Purposes of the STIP include:

  • Summarize the management activities conducted by the Town of Tiburon since the adoption of the OSRMP and the general process for scheduling and implementing these management activities;
  • Identify any major changes in the environmental setting (vegetation, sensitive natural resources) and recommended treatment methods based on current conditions or best management practices (BMP);
  • Re-establish the prioritization categories for management activities;
  • Identify the specific projects, programs, or management actions to be implemented by the Town over the next five years and beyond, consistent with the OSRMP and based on current conditions;
  • Provide an annual schedule that specifies the recommended activities for implementation; and
  • Specify any recommended monitoring of management actions.Invasive grasses

The STIP is very detailed regarding what invasive or flammable species to remove on all 26 open space parcels within the Town of Tiburon.  The Commissioners were especially impressed by the detailed cost estimates for vegetation management on each parcel for each of the first five years.  These amounts had been arrived at by interviewing other land managers in Marin County.

LSA asked me to review the document because of my years of involvement with the parcel. In my comments I will emphasize:

Professional Dog Walkers

  • The ongoing destruction by dogs brought daily by professional dog-walkers to the Middle Ridge:
    • Their use tramples the serpentine grassland.
    • This use also impacts the habitat of three federal and state-listed species – Tiburon jewel-flower (Streptanthus glandulosus ssp. niger), Marin dwarf flax (Hesperolinon congestum) and Tiburon paintbrush (Castilleja affinis ssp. neglecta) – as well as a CNPS Rank 1B species, Tiburon buckwheat (Eriogonum luteolum ssp. caninum).
    • There is no enforcement of the professional dog-walking Ordinance (2016) (after several requests to the Police Department).
  • Echium candicansInvasion of Pride-of-Madeira (Echium candicans). This immensely invasive shrub is spreading into the open space from plants within the 100-foot encroachment space on parcels bordering the MR preserve.