The Asian Citrus Pyllid (ACP) is a threat to the citrus industry, and has been rapidly spreading since 2008 when the ACP was first detected in California. There is currently no way to stop it. Some of the ACP carry a Huanglongbing (HLB) bacteria that affects the new growth of citrus trees and causes citrus greening disease, where the fruit does not ripen and the tree eventually dies.

This citrus industry is looking into ways to slow the spread as well as alternative treatments, from genetic modification of the Psyllid to make them sterile to disease resistant root stock.  Recent research into resistant varieties, organic probiotics and learning from surviving trees in Florida has given some hope for the long-term future of citrus production, especially for organic citrus. Most of this research has been taking place in Florida, where the disease was found in 2005 and has devastated the citrus industry there.  More information HERE  from the AGNET West website.

The California Data Analysis and Tactical Operations Center (DATOC) provides rapid, flexible, and responsive management plans for combating Huanglongbing and the Asian citrus psyllid in California citrus. Read more about them HERE

DATOC has been requested to analyze California Department of Food and Agricultres’s program activities combating HLB in Southern California for efficiency and effectiveness.  They found that more than 1,500 HLB-infected trees have been found in over 20 cities in Southern California.

In 2017 DATOC produced a briefing paper that summarized the history of the development of the HLB epidemic and expansion of ACP.  DATOC said in their 2017 report titled “State of the STATE”:

“Over the last year, there has been a dramatic increase in the rate of new detections of HLB infections in both ACP and citrus trees. In addition, there has been a recent increase in the number of cities in which positive finds have been reported and a sharp increase in the number of ACP nymph detections.”

To avoid the escalating exposures to pesticides being recommended by CDFA, the time has come for local management and control so communities like Ojai can work together to save our citrus. Citrus growers, residents of the unincorporate areas of the County and City of Ojai, regulators and pest control advisors need to come together to get 100% participation on ways to take care of our citrus trees in the Ojai Valley. This will require providing information on organic treatments when possible, removing trees if needed, and taking care of citrus trees to promote healthy immune response with organic soil nutrients using compost, mulch, wood chips and irrigation to remove stress on the trees. Pesticides should be a last resort, not the first as is currently the case.

The ACP quarantine areas have spread rapidly and pesticides are voluntarily being applied by growers in hopes of buying more time for finding a treatment. A recent map of the current ACP quarantine area (in blue) and HLB treatment areas (in red) show the most recent expansion of ACP up into the Sacramento area.  The orange areas on the map below are concentrations of commercial citrus growers where pesticides treatments are voluntarily being applied up to 4 times per year as recommended by California Department of Food and Agriculture.

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The ACP Statewide Management Program for the ACP / Huanglongbing (HLB) (bacteria) is guided by the Secretary of the California Department of Food and Agriculture (CDFA) with guidance from the  California Citrus Pest And Disease Prevention Committee (CCPDPC).  See their website for links to meetings, minutes and strategies.  Their next meeting is scheduled for Tuesday, November 12, 10-4 at the Crown Plaza in Ventura. The current  methodology/treatment options by CDFA for the ACP are here and consist of research into treatment methods, quarantines, followed by pesticides, fence barriers, spraying fence barriers, followed by more frequent application of even more pesticides.

The most recent attempt at a treatment plan for Ventura County growers is coming came from researchers and academics at UC Riverside. Below is a slide from a power point presented at the spring meeting of Ventura County ACP-HLB Task force. This shows pesticide treatments are expected to escalate.

Screen Shot 2019-09-16 at 2.29.36 PM.pngOn July 29, 2019, California Dept of Food & Ag. issued an Official Notice of Treatment for Ventura County along with a map showing  the location of the ACP Treatment Areas.

Notice of Treatment (NOT):

Excerpts from the VC Official Notice of Treatment are below:





… In accordance with integrated pest management principles, CDFA has evaluated possible treatment methods and determined that there are no physical, cultural, or biological control methods available to eliminate the ACP from this area. Notice of Treatment is valid until June 12, 2020, which is the amount of time necessary to determine that the treatment was successful.

The treatment plan for the ACP infestation will be implemented within a 400 -meter radius (equals approximately 400 yards, 1/4 mile or 4 football fields) of each detection site, as follows:
•Tempo® SC Ultra (cyfluthrin), a contact insecticide for controlling the adults and nymphs of ACP, will be applied from the ground using hydraulic spray equipment to the foliage of host plants; and
•Merit® 2F or CoreTect™ (imidacloprid), a systemic insecticide for controlling the immature life stages of ACP, will be applied to the soil underneath host plants. Link to Q & A on Merit is here and  CoreTect™ is here 

Click to access HQA_Coretect_ACP_English.pdf

Merit® 2F is applied from the ground using hydraulic spray equipment. CoreTect™, which is used in place of Merit® 2F in situations where there are environmental concerns about soil surface runoff of liquid Merit® 2F, is applied by inserting the tablets into the ground and watering the soil beneath the host plants.

Public Notification:  Residents of affected properties shall be invited to a public meeting where officials from CDFA, the Department of Pesticide Regulation, the Office of Environmental Health Hazard Assessment, and the county agricultural commissioner’s office shall be available to address residents’ questions and concerns. Residents are notified in writing at least 48 hours in advance of any treatment in accordance with the Food and Agricultural Code sections 5771-5779 and 5421-5436.

Following the treatment, completion notices are left with the residents detailing precautions to take and post-harvest intervals applicable to the citrus fruit on the property.

More Information on Pesticides used from CDFA’s Website Under HOT TOPICS

What to Expect when CDFA is Inspecting, Trapping and Treating


A state mandated quarantine was initiated for Ventura County back in December of 2010 for the ACP.  A quaratine is an attempt to isolate and control spread of harmful insects, restricting their movement and requiring spraying and treatment to contain, manage and control populations.

Area Wide Management (AWM) was initiated in 2016 to coordinate growers for the management and treatment of insects in a quarantined area to reduce spread of the insect.  The AWM for Ventura County was initiated by the Ventura County ACP-HLB Task Force, which is a growers organization organized in 2010 and supported by the VC Farm Bureau to:

“coordinate an effective industry response to the threat posed by the Asian citrus psyllid, with the goal of achieving maximum suppression of the ACP population and delaying the introduction and potential spread of Huanglongbing disease.”

HERE is a dropbox folder with the ACP-HLB Task Force presentations and maps showing treatment areas in Ventura County.

Their contact info is 805-289-0155
Link to their Facebook page:
In Ventura County, the University of California Division of  Agriculture and Natural Resources   “strategy for all regions is to minimize the number of extra pesticide treatments applied for ACP in order to preserve IPM programs and reduce the risk of resistance. ”  More info HERE
The 2019-2020 Area Wide Management Plan for treatment is attached below.
2019-2020 AWM schedule final


Early Detection options are less toxic with more info HERE

Background info on ACP/HLB
-UC IPM Pest Notes