The California Department of Food and Agriculture (CDFA) has issued hold orders covering the areas where six Asian citrus psyllids (ACP) were recently detected on three traps south of the city of Porterville. The latest interceptions, which bring the number of psyllids found in Tulare County to nine, are of particular concern because they were made in the heart of California’s chief commercial citrus growing region.
The hold order is a temporary measure to reduce the risk of spread while a quarantine is assembled, said CDFA spokesman Steve Lyle. The hold orders affect the three areas with a five-mile radius – an area surrounding each find site. “At the moment, fruit may move if it is free of leaves and stems,” he said. “The hold order applies to host plants only.”
The Asian citrus psyllid is an invasive species of grave concern because it can carry the disease huanglongbing (HLB), also known as citrus greening. All citrus and closely related species are susceptible hosts for both the insect and the disease. There is no cure once a tree becomes infected. The diseased tree will decline in health, producing bitter, misshaped fruit until it dies. In California, HLB has been detected on just one residential property in the Hacienda Heights neighborhood of Los Angeles.
The president of California Citrus Mutual, Joel Nelsen, said hold orders are more onerous for nurseries than growers because they can’t move the plant if it had not met specific criteria for production prior to the ACP detection. “Basically there is no makeup clause in their rules,” he said. “For growers, mitigation steps can be taken to move fruit out of the quarantine area and documentation to that effect has to be submitted before the harvesting of the fruit can take place.”
Nelsen explained that the steps were put into place because of the pest’s behavior. “Fruit by itself is not a carrier for ACP for the most part; stem and leaf trash in the bins can be, so a spray program is necessary,” he said. “For nursery stock the trees could be infected and the psyllid can hide within the plant and avoid the contact spray, so that’s why plants can’t move.”
In effect, nurseries lose the cost of production and the plant itself because it will most likely be held past a reasonable shelf life, said Nelsen. For growers the cost is an added spray which hopefully gets made up via a higher FOB. “At least the grower can generate some revenue,” he said. “The nursery guy could be stuck if he had not taken the necessary precautions in the past several months.”
The Tulare County Agricultural Commissioner’s Deputy Commissioner/Sealer, Standards & Quarantine, Gavin Iacono, said that currently there isn’t much for area growers to do in response to the orders. “Right now we’re in a holding pattern,” he said, urging growers to attend an informational meeting this coming Tuesday.
The Citrus Pest and Disease Prevention Program is holding a meeting for growers and pest control advisers Tuesday at the International Agri-Center, 4450 S. Laspina St. in Tulare. Doors open at 8 a.m. and the program will begin at 9 a.m. According to an announcement posted by California Citrus Mutual: “This meeting is your opportunity to learn how the recent ACP finds and subsequent regulations will impact your operation,” it states. “Commercial growers in the immediate areas surrounding the finds will be required to treat, and quarantine areas will be defined that will restrict the movement of bulk citrus and nursery plants.”
The specifics of the quarantine will be addressed by Tulare County Ag Commissioner Marilyn Kinoshita. Victoria Hornbaker, program manager for CDFA and the Citrus Pest and Disease Prevention Program, will give an update on the program’s activities. Nawal Sharma, environmental program manager at CDFA, will join Kinoshita in providing a summary of the newest regulations for Tulare County, followed by an overview of the treatment notification procedures by Tulare County Grower Liaison Bob Wagner.
In addition, the new president of the Citrus Research Board, Ken Keck, will offer a Florida perspective on area-wide treatment strategies, and Debby Tanouye, chief of CDFA’s Pest Detection Emergency Program, will discuss urban and residential treatment and survey results. Finally, Beth Grafton-Cardwell, IPM specialist and research entomologist at University of California-Riversides’s Department of Entomology, will cover ACP sampling and treatment strategies.
California Citrus Mutual is highly recommending that growers attend. There is no cost, but RSVPs are requested and can be made by contacting Emma at the Citrus Research Board, 559-738-0246, or firstname.lastname@example.org.