Sudden ACP Increase in California Worrisome

Len WilcoxCalifornia Corner, Psyllids


To the surprise and consternation of growers and officials, 74 Asian citrus psyllids (ACP) have been discovered in Kern County, California, since June. Local and state officials are concerned about the recent uptick in trappings and are working to find how extensively the infestation has spread.

The trappings have been equally dispersed in residential and commercial citrus. Staff from the California Department of Food and Agriculture Citrus Pest and Disease Prevention Division (CPDPD) are working on area treatments and getting delimitation traps set up.

“We want to see what is the extent of the infestation. We’re putting many more traps out there than we would normally have. Those traps are initially monitored every week,” said CPDPD Director Victoria Hornbaker. “Also, we’re doing that visual survey to see if we can find live insects. Are we seeing nymphs? Are we seeing eggs? In a couple of properties, we did find some nymphs.”

A similar upsurge in ACP populations occurred several years ago in Kern County. The increased ACP discoveries were successfully addressed, and numbers were brought back down.

The overwhelming majority of ACP finds have been in southern California, making the rise in discoveries north of the grapevine more concerning. Despite mitigation efforts, it is likely the pests are being unwittingly transported by industry members.

“We’re going to be working with our regulatory staff to take a look at that; working with Kern County to find out what they’re seeing coming over the grapevine into Kern County,” Hornbaker noted. “Then we’ll work with the haulers, the growers and the packers to make sure that they all remember that tarping is required regardless of where you’re moving (citrus) to or from.”

Safety measures for limiting the spread of ACP go beyond tarping citrus shipments. Paying close attention to the movement of people and equipment can help address the uptick in ACP discoveries. Hornbaker suggests thorough sanitation efforts be adopted for cleaning picking bags, trucks, tractors and other equipment. Individual actions such as keeping windows rolled up while on citrus worksites can also play a role in limiting ACP transport.

“A psyllid can inadvertently fly into a vehicle and be transported that way,” said Hornbaker. “So, clean off your clothing when you’re going into a grove and brush yourself off — anything that we can do to prevent that inadvertent movement of an ACP from one area to another. We want people being very diligent.”

Read about the recently amended citrus movement rules designed to protect commercial groves from the threat of citrus greening, the disease carried by ACP.

Source: AgNet West