Subtropical Fruit Crops Research & Education
University of California
Subtropical Fruit Crops Research & Education

We are San Diego & Riverside County Farm Advisors

HLB - Potential Threat Near San Diego County

HLB detected in Riverside County: 

The Asian citrus psyllid is a tiny, mottled brown insect about the size of an aphid that poses a serious threat to all of California's varieties of citrus (e.g., oranges, grapefruit, lemons, and mandarins).


The insect is associated with the fatal citrus disease Huanglongbing (HLB), also called citrus greening disease. The psyllid takes the bacteria into its body when it feeds on bacteria-infected plants and spreads when a bacteria-carrying psyllid flies to a healthy plant and injects bacteria into it as it feeds.

HLB can kill a citrus tree in as little as five years, and there is no known cure. All commonly grown citrus varieties are susceptible to the disease.

The only way to protect trees is to prevent spread of the HLB pathogen in the first place, by controlling psyllid populations and removing and destroying any infected trees.

Learn more about HLB and how to protect your crops from it by following these links. 


News Stories: 

Distribution & Management: 

IPM Blog: 

IPM Pest Notes 

California Citrus Pest & Disease Prevention Committee: 

Topics in Subtropics Blog

  • Ag Expert on Fuller Rose Beetle and CEUs

    Added December 12, 2018
    fuller rose beetle

      UC Ag Expert talks about                                 Fuller rose...

  • Ground Squirrels Thrive Year-Round in Avocado Orchards

    Added December 10, 2018
    ground squirrel

    Ground squirrels eat a variety of fresh greens as well as seeds and dried nuts. In spring, ground squirrels prefer greens over seeds and nuts.  Once the natural grasses begin to dry and wither, squirrels will actively forage for seeds.  As...

  • Get that Tubing Right

    Added December 7, 2018

    While conducting surveys across Merced County, I have noticed diverse ways growers secure the ends of irrigation tubing.  Many are attached using some type of stake made of wood or PVC in which the tubing is tied. Other orchards have the lines...

  • Citrus Forum

    Added December 5, 2018
    citrus forum

    The University of California Cooperative Extension office in Tulare County, is launching a new website to facilitate exchange of information among individuals involved in citrus production in California, from growers to...

  • Which Way HLB - Huanglongbing and Asian Citrus Psyllid? Now in Marin.

    Added November 30, 2018
    ACP adult and nymph

    The best way to delay arrival of HLB in our area and minimize its impact is to keep ACP suppressed down to the lowest level possible.  By treating in coordination with neighbors in an areawide approach, grower ACP treatments can have a greater...

  • Great Citrus Tasting!!!!

    Added November 30, 2018
    lindcove fruit tasting

    Date: December 15, 2018 Time: 9:00 AM - 12:00 PM Contact: Jasmin Del Toro: 559-592-2408 ext 1151 Sponsor: Lindcove Research and Extension Center Location: Lindcove Research and Extension Center Event Details The...

Avocado Production in California Books

Book 1: Background Information

In Book 1, Gary S. Bender, Farm Advisor, takes you through the history of the avocado industry in California and teaches you about grove development.

Browse by Chapter

Book 2: Cultural Care

Book 2 focuses on cultural care and includes articles on irrigation, fertilization, disease and insect control, vertebrate pest management, pruning and frost management. The author for most of the articles is Gary S. Bender, Farm Advisor for Subtropical Horticulture in San Diego County.

Browse by Chapter

Webmaster Email: