New Report Dives In to Cross-Boundary Invasive Plant Survey Results from Mount Tam

July 2020 - Invasive plants don’t see our property lines. The five partners that make up Marin County’s One Tam partnership know this, and they teamed up to create an Early Detection and Rapid Response (EDRR) program tasked with identifying and managing invasives spanning the jurisdictions on Mt. Tamalpais.

With early leadership from the Inventorying and Monitoring Network’s Invasive Species Early Detection Program (ISED), crews from One Tam surveyed over 400 miles of roads, trails, and riparian corridors, identifying priority species and treating small patches where practical. The collaborative protocol drew heavily from the ISED protocol from 2009. In the process, the team standardized tracking data across the partnership and created a flexible staffing model to help fill essential gaps in treatment capability. The work, which will be repeated on a three-year cycle, ensures that invasive species new to the mountain are detected quickly and managed at cost-effective stages.

The EDRR team has now released a full report on its work from the first survey cycle, offering deep analysis of survey efforts and detailed strategies for addressing the mountain’s most formidable weeds. Data analyzed from this report include ISED data and weed treatment data from Marin work groups within the Golden Gate National Recreation Area. The analyses show that so far, early detection and rapid response seems to be working. Some of the highest priority weeds were more widespread than expected, like traveller’s joy (Clematis vitalba) in the Redwood Creek watershed. But several other top priority species declined year to year.

The early detection work is a cornerstone to One Tam’s efforts to protect the mountain’s iconic landscapes, and the plants and animals that call them home. Read the full Beyond Boundaries report to learn more.

For more information

• One Tam Invasive Plant Monitoring & Management webpage

• San Francisco Bay Area Inventory & Monitoring Network Invasive Plants Early Detection webpage
• Contact One Tam Conservation Management Specialist Rachel Kesel

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