The California Department of Food and Agriculture’s (CDFA) treatment for the Asian citrus psyllid is underway in Santa Barbara County, drawing mixed responses from affected residents.
The psyllid is a small insect that feeds on the young chutes, stems, and leaves of citrus trees. CDFA representative Jay Van Rein said that while the insect itself doesn’t pose much of a threat, it could carry a bacterial disease called huanglongbing (HLB). HLB, also called citrus greening disease, has no cure, and it’s fatal to all citrus trees it infects.
The psyllid was first found in the United States in Florida in 1998, where resulting cases of the disease devastated citrus growth. The insect has since spread to several states, including California.
On Jan. 8, the CDFA put out a notice that a breeding population of the Asian citrus psyllid had been detected in cities through Santa Barbara County, including Solvang in North County. The agency hasn’t yet found cases of citrus greening in the area, and Van Rein said the psyllid population in Santa Barbara County is an “isolated infestation.”
“We have an infested area surrounded by a larger area that’s not infested,” Van Rein said. “In that case, we have a chance to try to prevent or slow the spread.”
Santa Barbara County has been in quarantine for the psyllid since 2013, meaning anyone in the county who grows and harvests citrus—especially commercially—must avoid moving the pests around by omitting young chutes, stems, and leaves from all fruit they ship out.
“The quarantine is basically a regulatory design to keep the insects from moving,” Van Rein said.
The most recent CDFA notification announced further action against the bug. The agency is administering its Asian citrus psyllid treatment work plan, which includes two phases of insecticides to be applied within 400 to 800 meters of each detection site.
The first phase of treatment, which began on Jan. 27, is a foliar application of cyfluthrin. The pesticide is intended to kill adult psyllids and prevent them from laying eggs in the spring.
The foliar insecticide is applied from the ground to host plants’ leaves using hydraulic spray equipment. Van Rein said the pesticide dries in about four hours, after which affected fruit should be safe to harvest. Once dry, the insecticide will withstand rain.
Phase two will likely come in the fall, and it will involve a systemic insecticide. Systemics are applied to the host plants’ soil for the plants to absorb into their systems, and they provide longer-term protection by working from the inside out.
The CDFA’s systemic pesticide of choice is imidacloprid, a type of neonicotinoid and the subject of a recent preliminary risk assessment report by the Environmental Protection Agency (EPA). The report identified imidacloprid as harmful to honeybees, making its application a controversial issue among beekeepers and bee activists.
The CDFA notifies affected residents at least 48 hours before treating their land, after which it’s the residents’ responsibility to contact the agency and opt out if they wish not to participate. The CDFA will distribute a new wave of notifications for each phase of treatment.
Van Rein emphasized that this treatment plan is to manage, not eliminate, the psyllid.
“We have an insect that’s very difficult to eradicate, even in the best of circumstances,” he said. “But we do have the ability to slow its spread and control its movement to protect both commercial and backyard citrus from the prospect of the disease following the insect.”
Paul Towers, media director for the Pesticide Action Network of North America, said damage control is the only viable option when facing the Asian citrus psyllid.
“To think we can eradicate them is a little harsh,” Towers said. “What we can do is set ourselves up for the best management of them.”
Stopping the insects’ spread is also virtually impossible, he said.
“This is part of the overall challenge of the issue of globalization and global trade,” Towers said. “There are increasing pressures and increasing movement of pests beyond borders.”
And as long as those pressures exist, the spread will continue.
“There’s no way to totally stop these pests from coming across our borders, especially with the global economy,” Towers said. “It’s just going to keep happening.”
Many affected residents—including organic growers and bee activists—aren’t on board with the CDFA’s pest management tactics.
On Jan. 18, affected SB County resident Jay Hennigan posted on an online community forum, edhat.com, that he had received a treatment notice from the CDFA and wanted to know how to opt out.
“As one who maintains a pesticide-free garden, I’m opposed to having the state apply poisons to my fruit trees,” Hennigan wrote.
Comments followed, expressing a range of opinions on the ethics of the Asian citrus psyllid treatment program.
One commenter wrote, “I would rather have my citrus trees die than poison my soil and the wildlife that inhabits my yard.” Another: “I’m not thrilled with the idea of spraying the trees in my yard, but I want to do my part to protect my neighboring lemon grower.”
Many commenters expressed that they had tried to contact the CDFA to opt out of treatment, but found it difficult to do so. Others, such as Kevin Hanson, who has property in Goleta, took issue with the CDFA’s refusal to allow growers to permanently opt out of all future pesticide treatments.
“They typically follow up by saying that the only way to refuse treatment is to wait until you have received a 48-hour spray notice and then call their number,” Hanson wrote in an email to the Sun. “They clearly have a list they are scheduling treatment from and could easily offer opting out at any time, but are putting measures in place ([such as a] short timeframe, at an unknown time) to make it difficult to refuse treatment.”
So Hanson created pesticideoptout.com in an attempt to compile a permanent pesticide opt-out list.
“While we understand the severity of the issue and the need to do something, CDFA is putting the responsibility of opting out of a non-organic treatment on all those in the affected areas, as opposed to them taking on the responsibility of asking people to participate,” he wrote.
In an interview with the Sun, Hanson said most growers he knew would participate in the treatment if an organic option was available.
“Pretty much everyone I’ve talked to doesn’t actually want to opt out,” he said. “They just wat an organic option.”
The CDFA’s Asian citrus psyllid treatment program was scheduled to begin on Monday, Jan. 25, but due to an influx of inquiries from growers wishing to opt out, the agency pushed the start date to Jan. 27.
The duration of the program’s first phase will depend on the weather, Van Rein said. He added that affected residents should relocate their outdoor pets.
“We generally ask with all of our treatments for people to have their pets secured indoors while we have our staff on the property doing our treatment,” he said. “If people have food or water dishes out, or for that matter play equipment or pools, we are equipped to cover those during the treatment.”
Van Rein said that the CDFA is exploring sustainable, biological options for Asian citrus psyllid management, specifically, options like introducing a natural predator to help control the pest population.
“Any time that we can find a treatment that involves a natural predator or a natural parasite or something like that, when we have a program that’s going to be conducted over the longer term, those are much preferable options,” he said.
The Asian citrus psyllid’s natural predator is Tamarixia, a small, stingless wasp. Van Rein said the CDFA is looking into introducing Tamarixia to Santa Barbara County after the current treatment plan completes.
“We’d be able to gain natural suppression over a larger area for a longer period of time that is also self-sustaining and doesn’t require repeated applications,” he said.
Introducing a natural predator is an example of integrated pest management (IPM), which California Department of Pesticide Regulation Assistant Director Charlotte Fadipe said is the ideal method for pest control. With IPM, pesticides are a last resort.
But it’s not always as effective, Fadipe said.
“We encourage people to do IPM, and sometimes they do find it doesn’t work or doesn’t work well enough,” she said. “I know people find imidacloprid very effective, and that’s why they want to use it.”
Residents wishing to opt out of treatment can do so any time after receiving a treatment notice from the CDFA by calling the agency’s pest hotline at (800) 491-1899.
Staff Writer Brenna Swanston can be reached at bswanston@santamariasun.com.
This article appears in Feb 4-11, 2016.