Citing the growing threat of non-native plants to the local ecosystem, the National Park Service is creating a master plan to combat the trend in its Santa Monica Mountains that could include the use of herbicides. But in Topanga, one environmental group is arguing the use of herbicides would harm the environment worse than encroaching non-native plants.
Ben Allanoff, chair of the Topanga Creek Watershed Committee, which successfully fought a policy change in 2011 by Caltrans to use herbicides to spray brush alongside Topanga Canyon Boulevard, said studies show herbicides can cause issues such as mutation in plants and animals that were not targets of the chemicals sprayed.
“The dangers caused by chemicals can be much worse than whatever damage plants can cause,” Allanoff said.
Allanoff’s comments came on the heels of meetings last week in Thousand Oaks and Pacific Palisades, where park service officials met with community members to gather input on the plan and explain the effect of unwanted shrubbery in the 150,000-acre mountain range.
“Invasive non-native plants now infest approximately 2.6 million acres in the National Park System, which covers over 84 million acres,” David Szymanski, superintendent of the Santa Monica Mountains National Recreation Area, wrote in a summer newsletter. “Many are highly invasive and can alter native plant communities and the wildlife that depends on them.”
Kate Kuykendall, public relations officer for the NPS in the SMMNRA, said the park service currently uses herbicides like glyphosate (Roundup) on a limited basis, including in Malibu. The purpose of the plan is to develop a comprehensive strategy, she said.
“The reason that we’re doing an ongoing assessment now is because it’s kind of been a patchwork,” Kuykendall told The Malibu Times. “The purpose of this is we want to have an overarching strategy, and we want to have input from the public.”
The NPS newsletter presents a series of potential options governing herbicide use under the eventual master plan. One option would be the use of a limited number of herbicides “selected for their effectiveness, small effects on wildlife, soil, and water and for their minimal health risks for people applying them and the general public,” according to the newsletter.
This option is a continuation of current programs that include the continued use of mechanical, cultural and chemical treatments, the newsletter states.
A second option, titled “Additional Invasive Plant Managements,” would offer additional tools on top of the status quo, mentioning the use of grazing livestock or other biological control methods. The four-page document is available for download on the NPS website.
NPS’s land in the Santa Monica Mountains stretches from the Oxnard plain to Hollywood Hills and includes Malibu’s beaches.
Allanoff, a Topanga resident since 2000, believes there are ways to get rid of the unwanted vegetation without chemicals, such as bulldozing or spreading mulch or woodchips after cutting the plants.
“It all depends on the situation,” he said. “The right tool for this spot may not be the right tool for that spot.”
In his group’s past work with Caltrans, Allanoff cited as an example the successful use of mulch on roadsides, which disabled the growth of plants and prevented seeds from getting into the ground.
Kuykendall said the Parks Service was open to different solutions depending on the area.
“We agree 100% that different solutions should be applied in different areas, and one of the alternatives we’re proposing is an adaptive management approach that will allow us to apply new information and different approaches depending on the circumstances,” she said.
When asked if financial considerations factored into the proposed normalization of the use of herbicides as brush maintenance, Kuykendall acknowledged that they are less expensive.
Because mechanical treatments (brush-cutting, mowing, etc.) may require multiple applications in order to eliminate the target species, mechanical treatments are often more expensive than chemical treatments.
Allanoff said studies funded by chemical companies say herbicides do not damage anything other than the targeted weeds, while independent studies suggest chemicals hurt the environment.
For example, in April the scientific journal, Entropy, released a study that said the chief ingredient of the popular herbicide Roundup can be linked to health issues such as cancer, infertility and Parkinson’s. Roundup’s developer, Monsanto, shot back and said the weed killer is safe.
“Chemical companies test under laboratory conditions,” he said. “The environment contains other elements and pollutants, so there is no way to test what happens when those chemicals come in contact with them.”
Individuals have until October 1 to submit comments on NPS’s plan by mail to Santa Monica Mountains National Recreation Area, Attn: Invasive Plant Management Plan at 401 West Hillcrest Drive, Thousand Oaks, CA 91360 or on http://parkplanning.nps.gov/rs-inv-plants