The Point Reyes National Seashore has concluded that a plan to combat invasive plants with herbicides will have no significant impacts, despite opposition from scores of public commenters who charged that the risks of the toxins on sensitive dune ecosystems are too great to move ahead with the project.
The preferred alternative in the seashore’s Coastal Dune Restoration plan will use a combination of manual removal, mechanical excavation and the application of two herbicides on 600 acres of dunes as funding becomes available. The Finding of No Significant Impact, or FONSI, along with public comments on three alternatives presented in the plan and the park’s response to them, was released last week.
The vast majority of the roughly 100 commenters live in Marin or the Bay Area. Critics who lambasted the prospect of herbicide use include the executive director of the Environmental Action Committee of West Marin; other conservation groups, like the Marin chapter of the California Native Plant Society and environmentalist Gordon Bennett’s Save our Seashore, supported the park’s plan.
“It’s certainly a last resort for us,” said seashore spokesman John Dell’Osso. “We have found, over 15 years of doing work in dunes, that a combination of what we’re planning on doing will probably work best. We take a lot of real precautions with the spraying.”
The park will use two herbicides—glyphosate, in a formulation known as “Roundup Custom,” and imazapyr—to combat non-native European beachgrass and iceplant on 600 acres of dunes. Currently the park has roughly $450,000 for a 110-acre site south of Abbotts Lagoon.
The first year of the project, to commence this fall, will consist of hand-pulling iceplant and mowing and burning beachgrass; next year the park will begin herbicide treatment. Because of constraints like nesting birds and breeding red-legged frogs, work will generally take place between August and October.
The plan addresses three distinct areas: North Beach and what’s called the AT&T area, near the former maritime radio receiving station; the A Ranch, B Ranch and dunes near a former inholding inhabited by the late Ben Davis; and Limantour. In these areas, the dunes are covered in iceplant and European beachgrass, the latter introduced in the 19th century to stop sand from infringing on coastal properties. The invasives crowd out rare native plants like American dunegrass or endangered Tidestrom’s lupine, which provides nectar for Myrtle’s silverspot butterfly, another endangered species.
They also take up nesting ground for the endangered snowy plover, a shorebird that has struggled in the seashore but has expanded its nests around Abbotts Lagoon following that area’s recent restoration.
The draft plan, released in January, included three alternatives, each emphasizing a different technique: hand pulling, mechanical excavation and herbicide use. Alternative C, the preferred alternative, aims to pre-treat areas slated for herbicides by mowing and burning. In areas close to organic ranches or wetlands, excavators will be used instead, and in some cases patches of iceplant are small enough to be removed by hand.
But hand removal is not an option with European beachgrass, whose rhizomes can reach as far as 12 feet underground. In a previous restoration project at Abbotts Lagoon, excavators were used, but the park says that technique is prohibitively expensive. Mechanical or hand removal can cost over $30,000 per acre, whereas chemical treatment can cost $2,000 to $4,500 per acre.
A higher expense would mean future funding could cover much smaller areas; in the restoration at Abbotts, the cost reduced the project size from 132 to 80 acres.
The excavators also loosened sands at Abbotts to such an extent that it drifted onto a small area of pasture—a concern voiced by the Point Reyes Seashore Ranchers Association—and into wetlands. When seashore staff use excavators for the current project, they will swiftly plant natives to stabilize the sands.
Many public comments broadly protested the use of herbicides. “I find it horrific that the National Park intends to use Roundup, an herbicide which poisons our environment, as a means to ‘improve’ our environment,” a Point Reyes Station resident wrote. “We need to take care of our precious planet, not destroy it.”
Others enumerated a host of concerns about glyphosate in particular, including that it is carcinogenic and harmful to amphibians, butterflies and bees. Many comments worried about what surfactant—the agent that encourages the plant to absorb the herbicide—would be used, as some studies suggest that surfactants can be more toxic than the herbicide itself.
More than one person cited a study conducted for Marin Municipal Water District in 2011 that found glyphosate present in the leaves of plants for at least three months after an initial application.
Amy Trainer, the executive director of the E.A.C., asked the park to wait for a pending study of glyphosate by the Environmental Protection Agency. “I am concerned that the Seashore proposes to use the known endocrine disruptor glyphosate, the half-life of which is currently unknown when combined with the surfactant Competitor, in the Seashore, and particularly in wilderness areas,” she wrote. “I strongly urge against the Seashore implementing Alternative C.” (A few of her board members disagreed. Jerry Meral, for instance, the state’s former Deputy Secretary for Natural Resources, wrote in support of the park’s plan.)
The E.P.A. does not currently list glyphosate as carcinogenic. In 2013, after a review conducted in response to a petition by Monsanto (the corporation that makes glyphosate), the agency actually raised the allowable amount of glyphosate residue on some vegetables. But the agency is now conducting another review. The World Health Organization recently announced the results of its own review, and that it believes glyphosate is “probably carcinogenic.”
The park, Ms. Trainer said, should delay the use of herbicides—and instead use manual and mechanical methods—until the E.P.A. process is complete.
Lorraine Parsons, who is managing the restoration project, said the park relied on risk assessments created for the United States Forest Service in 2011 to assess the potential dangers of glyphosate and imazapyr. But, she added, “Should [the E.P.A.] release their findings and say, ‘You know what? We changed our minds we feel this might potentially be carcinogenic,’ that would be considered new info under [the National Environmental Policy Act] and cause us to reconsider.”
Other comments suggested using grazing animals, like goats, to eat the invasives.
The seashore’s response to the comments essentially reiterated or clarified its plan, enumerating the safeguards it intends to employ—using only handheld, targeted spraying as opposed to aerial spraying; avoiding spraying during windy or rainy conditions; blocking off sprayed areas for 24 hours; and using a surfactant than has been less widely critiqued. The response differentiated between the presence of glyphosate on the leaves—which it says evaporates in a few hours—as opposed to in the leaves, which is necessary to kill the invasives.
The seashore said it considered grazers, but said they would not be able to reach the rhizomes below ground, would probably not eat iceplant, and might also eat rare or native plants, too.
The response also downplayed and disputed the wide-ranging claims of harm from herbicides. Although the FONSI admitted that glyphosate can have “adverse effects on human health,” it said studies typically use high concentrations of the chemical and often in conjunction with a surfactant the seashore says it will not use. Competitor—the chosen surfactant—has not been as studied as others, but it is comprised of ingredients used in cosmetics and pharmaceuticals, Ms. Parsons said. “This is a product that is essentially modified vegetable oil,” she added.
The park is using a formulation of glyphosate she said is approved for use in water and wetlands.
Ultimately, the seashore concluded that the risks to human health were minimal. “The only exposure routes that could increase risk to a level where it is of concern,” the FONSI states, “are ones that are extremely unlikely, involving children drinking water in ponds where herbicide has accidentally been dumped or women of reproductive age eating European beachgrass or iceplant.”