ANR Employees
University of California
ANR Employees

Posts Tagged: Beth Grafton-Cardwell

Arroyo Grande psyllid has caused a big stir

One sign of potential Asian citrus psyllid infestation is waxy tubules on new growth. (Photo: M.E. Rogers)
The discovery last month of one Asian citrus psyllid on a sticky trap perched in an Arroyo Grande lemon tree has the citrus industry and agricultural commissioner on guard, reported Jono Kinkade in the San Luis Obispo New Times.

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.

Posted on Thursday, April 10, 2014 at 2:05 PM

Dinuba Asian citrus psyllids the most ever found in the Valley

UC Cooperative Extension's Beth Grafton-Cardwell is one of the state's leading experts on Asian citrus psyllid.
More than 100 Asian citrus psyllids were found on three backyard orange trees east of Dinuba, reported Robert Rodriguez in the Fresno Bee. The homeowner told officials the trees were planted in April 2012 and were acquired from a private party, not a nursery.

"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,

The website advises farmers and homeowners to regularly conduct visual surveys for Asian citrus psyllid and tap sample (see video) trees in their orchards.


Posted on Thursday, September 12, 2013 at 8:17 AM

Numerous Asian citrus psyllids found in Dinuba

The UC ACP website, which provides information to farmers and home citrus growers at
Numerous Asian citrus psyllids were found in east Dinuba and traced to recently planted backyard orange trees, according to reports in The Business Journal in Fresno and The Fresno Bee.

“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.

Posted on Wednesday, September 11, 2013 at 11:47 AM

New Asian citrus psyllid website helps farmers and homeowners connect the dots

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

The new Asian citrus psyllid website can be found at
The new Asian citrus psyllid website can be found at

Posted on Wednesday, August 21, 2013 at 12:04 PM

Reaching the public critical when contending with invasive pest threats

Citrus shoot infested with Asian citrus psyllid. (Photo: M. E. Rogers)
The discovery of Huanglongbing disease in a Hacienda Heights backyard last month poses a new challenge for UC Cooperative Extension and other scientists, reported Kate Campbell in AgAlert.

"We're really good at providing detailed information to researchers, agricultural commissioners, Cooperative Extension advisors, inspectors and border protection agents about what to look for and how to respond," said Beth Grafton-Cardwell, UC Cooperative Extension specialist in the Department of Entomology at UC Riverside. "We can reach thousands of people that way."

But with Asian citrus psyllid and Huanglongbing, "we're dealing with backyard situations, which is a whole new ballgame."

Campbell attended a conference in Davis last week focused on "Educating the public about new invasive species threatening California's plant ecosystems." Conference topics -- Huanglongbing disease, Asian citrus psyllid, light brown apple moth (LBAM), quagga and zebra mussels, European grapevine moth, sudden oak death, Japanese dodder, gold-spotted oak borer and red palm weevil -- were addressed by scientists, public officials, a public relations professional and a Sacramento Bee reporter.

"The public needs to be a partner in our efforts to respond to an invasive pest threat," said UC Davis post-doctorate researcher Margareta Lelea, who studied public reaction to LBAM treatments in Santa Cruz. "We need to figure out how we get to shared issues that the public cares about. The community has to be heard and feel like a partner in solving pest problems."

Posted on Wednesday, May 2, 2012 at 9:15 AM

Next 5 stories | Last story

Webmaster Email: