Arborist crew removing acacia shrubs from the Palos Verdes Nature Preserve. Photo: Palos Verdes Peninsula Land Conservancy/pvplc.org

By Adrienne Mohan, Executive Director
Palos Verdes Peninsula Land Conservancy

While some wildfires are part of nature’s natural cycle, the images of flames burning Southern California hillsides and neighboring homes is alarming.  Since its founding in 1988, the Palos Verdes Peninsula Land Conservancy has expended significant human and financial resources on fuel load reduction management work that benefits both the safety of residents and wildlife on the peninsula. 

Removal of invasive weed species like mustard, acacia, and pampas grass, not only impact the quality of habitat on the Peninsula, but also address a major fire danger.  An acacia removal project was funded by the City of Rancho Palos Verdes this year to augment fuel modification by the city due to larger-than-expected amount of invasive weeds around the Peninsula caused by heavy rainfall followed by warm weather.  Removal of acacia is critical because it is comprised of approximately 90% dry plant matter and volatile resins, making it highly combustible.  It also blocks out native vegetation such as species that are both more fire resistant and more needed by local wildlife to survive.

The project supported the removal of 40 acres of acacia and another 61 acres of invasive mustard. The Conservancy has also worked closely with the other surrounding cities, such as the City of Rolling Hills, to remove potential fire hazards.  As Habitat Manager of the 1,400 Palos Verdes Nature Preserve, the Land Conservancy provides guidance on vegetation and natural resource management to reduce fuel load vegetation in compliance with the Natural Communities Conservation Plan (NCCP).  The plan requires meeting federal requirements to protect natural wildlife diversity such as monitoring, restoration planning and implementation.

A Conservancy biologist oversees the monitoring and documentation of project sites to prevent disturbing birds and other mammals.  This year, the Conservancy trained four Field Monitoring Interns from CSULB to identify plant and animal species and gather data using Geographic Information System (GIS) tools.  Data was gathered on areas where acacia had already been removed and documented any regrowth and seedling germination for retreatment.  Flora and soil samples were collected for each treated area, and monthly photo point monitored results. 

The acacia removal data collected this year are helping the Conservancy to develop a “Habitat Enhancement Plan” to identify strategic priorities for the additional removal of acacia and other combustible vegetation that will reduce the fuel load and maintain wildlife benefits for the foreseeable future.