They've established a quarantine zone within a five-mile radius of the ACP find and monitoring has been stepped up in the area. Officials are concerned because of the psyllid's ability to spread huanglongbing disease, should the disease make its way into California. (So far, only one backyard tree has been found in California infected with huanglongbing.)
“If you don't have a vector like a psyllid, no big deal, but when you have a vector alive and moving around, then you have a big problem,” said Beth Grafton-Cardwell, UC Cooperative Extension specialist in the Department of Entomology at UC Riverside.
The psyllid is established in some areas of Southern California and has been found in commercial orchards in the San Joaquin Valley, where an eradication plan is underway. In San Luis Obispo County, the main focus is on residential areas.
“It's so tiny that people don't even know they have it,” Grafton-Cardwell said. “It's very difficult to completely eradicate it because 60 percent of California [residences] have a citrus tree in their yard, so it can hop, skip, and jump.”
Comprehensive information about Asian citrus psyllid and huanglongbing disease is available on the UC ACP/HLB Distribution and Management website.
"It was incredible," said Fresno County entomologist Gene Hannon. "There were easily a dozen on just one small leaf."
Previous finds in the Valley numbered from one to three on yellow sticky traps in the Tulare County communities of Lindsay, Strathmore and Terra Bella.
Beth Grafton-Cardwell, UC Cooperative Extension specialist in the Department of Entomology at UC Riverside, said the number of psyllids in Dinuba means there is a reproducing population.
"And when that happens, we are off and running to getting an established population in the San Joaquin Valley," she said.
Grafton-Cardwell has worked with a team of UC researchers to provide detailed and scientifically sound guidelines for treating farm- and home-grown citrus infested with Asian citrus psyllid on a new UC Cooperative Extension website, http://ucanr.edu/sites/acp.
The website advises farmers and homeowners to regularly conduct visual surveys for Asian citrus psyllid and tap sample (see video) trees in their orchards.
“This is very surprising and very disappointing,” said Joel Nelsen, president of California Citrus Mutual in Exeter.
This was the third ACP find in Tulare County this year. An Asian citrus psyllid was discovered in Wasco, Kern County, last week.
The Tulare County Agricultural Commissioner, CDFA and USDA are conducting an extensive survey and treatment program in response to the new detection of ACP in Dinuba, according to a press release. Beth Grafton-Cardwell, UC Cooperative Extension specialist in the Department of Entomology at UC Riverside, wrote in her Citrus Bugs Blog that because all stages of the pest were found around the trees in Dinuba they were likely infested when they were planted.
"This situation points out the need to educate everyone that they must never move plant material from ACP-infested areas that are under quarantine to areas such as the San Joaquin Valley where the pest has not yet established," Grafton-Cardwell wrote.
Yesterday Valley Public Radio broadcast a 5-minute overview of Asian citrus psyllid with comments from Grafton-Cardwell.
"This is not just a commercial problem, but a homeowner problem because 60 percent of Californians have at least one citrus tree in their yard," Grafton-Cardwell said.
California Assemblyman Jim Patterson hosted an Asian citrus psyllid townhall meeting in Fresno in August. At the event, Grafton-Caldwell said it is vital to slow the spread of psyllid to new areas.
Along with conventional pesticide sprays, organic products have been tried to prevent spread of Asian citrus psyllid. However, the usefulness of the methods has come into question.
“We struggle with organics,” Grafton-Caldwell said, regarding organic sprays and powders. “They are short-lived and have to make direct contact with the psyllid. They are only good for hours or days and not for months.”
Information on monitoring for and treating Asian citrus psyllid and the disease it spreads is available online.
The early morning agriculture show on KMJ 580 in Fresno opened this morning with comments about UC's new Asian citrus psyllid website from Beth Grafton-Cardwell, UC Cooperative Extension specialist in the Department of Entomology at UC Riverside.
"There are a lot of websites out there relating to Asian citrus psyllid and huanglongbing disease," Grafton-Cardwell said. "What I tried to do in this one is give it a management focus with action steps: Here's where the bug and disease are, here's what you should do if you're a grower, here's what you should do if you're a homeowner. It connects the dots."
The story notes that the website includes a cost estimator for growers and homeowners that was developed by Karen Jetter, economist with the UC Agricultural Issues Center. The estimator lists effective pesticides and calculates the costs of application.
"It's a good way to figure out how you can help control Asian citrus psyllid," Grafton-Cardwell said.
The new website is at http://ucanr.edu/sites/acp.
Residents in the area have been notified, said Steve Lyle, spokesman for the California Department of Food and Agriculture. He said officials have used the same preventive approach in San Diego County since 2008, when the pest was first discovered locally.
Union Tribune reporter Chris Nichols added information in the article from UC's Asian citrus psyllid and huanglongbing disease website.
"The Asian citrus psyllid is a brown insect about the size of an aphid. It attacks new citrus leaf growth and causes the new leaf tips to twist or burn back. Most concerning, it can spread bacteria that cause a citrus-greening disease known as Huanglongbing or HLB, according to a description on the University of California’s Agriculture and Natural Resources website," the reporter wrote.