Invasive plant management efforts continue at Pillar Point Bluff, with crews back in the park treating invasive oxalis on Monday, January 24 through Friday, January 28.
Work to preserve the coastal scrub habitat at Pillar Point Bluff has been carried out for many years, since before the property became part of the San Mateo County Parks system. Prior to transferring the land to the county, Peninsula Open Space Trust began a multi-year effort to eradicate jubatagrass, an ornamental plant with origins in South America that is a noxious weed.
Our Natural Resource Management (NRM) staff and partners continue the work initiated by POST and have developed plans to identify, treat and monitor other invasive plants that threaten the bluffs.
Oxalis is a recently documented invader of the bluffs that releases chemicals in the soil inhibiting other nearby seeds from germinating. It has begun to aggressively spread preventing growth of native species such as grasses, forbs and shrubs.
NRM staff and contractors will use various approaches to target oxalis, including steaming, flaming and targeted herbicide application. For this phase of the project we will be using Weed Slayer Organic without biological amendment along with other herbicide formulations.
To learn more about alternative eradication methods including tarping, hand removal, flaming, compaction and targeted herbicide application that are being tested in San Mateo County Parks, view a report on The Efficacy of Various Methods for Treatment of Invasive Oxalis
At one time, jubatagrass occupied large sections of the bluffs obscuring views and making it challenging for native plants to survive.
Through hand removal and targeted use of herbicides, jubatagrass has been greatly reduced as shown in photos taken in 2008 and recently in 2021. Today, it is under control requiring only periodic manual treatment.
Sean Correa, Natural Resource Specialist