Hero Image

We are San Diego & Riverside County Farm Advisors

Effects of Drought and Botryophaeria Fungi on Permanent Crops

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).


“For more information on the Asian Citrus Psyllid, please click on “Exotic Pest” above”

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. 


Topics in Subtropics Blog
  • ACP mounted
    Which Way HLB/ACP?

    From: Cressida Silvers CA Citrus Pest and Disease Prevention Program ACP/HLB Grower Liaison Ventura, Santa Barbara and San Luis Obispo Counties 805 284-3310 (phone or text) ACP/HLB Resources   New and improved CDFA Citrus Division...

    By Ben Faber
    Author - Advisor
  • BidwellsBarsweetorangeCRC1512003
    Older is Better?

    Oldest orange variety released from quarantine   Stan Lim/UC Riverside German Rafael Villalba-Salazar, nursery technician, harvesting budwood from mother citrus trees at the UC Citrus Clonal Protection Program facility. The 1000th tree...

  • bff laying egg
    Black Fig Fly Today

    Black Fig Fly (Diptera: Lonchaeidae: Silba adipata) Invasive Fig Pest Recently Discovered in Southern California Click Here to Download the "Pest Alert" PDF Overview Fig growers need to be aware of the black fig fly (BFF), an invasive insect that was...

    By Ben Faber
    Author - Advisor
Riverside and San Diego County Newsletter
Issue Articles
Volume 1, Issue 3

Read our latest local newsletter 

Volume 1, Issue 2

Read our latest local newsletter 

Volume 1, Issue 1

Read our latest local newsletter 

Topic in Subtropics Newsletter

Issue Articles
Fall 2021

Click here to read this issue of the Topics in Subtropics newsletter.

Summer 2021

Click here to read this issue of the Topics in Subtropics newsletter.

PEST ALERT - Black Fig Fly

Avocado: Food of the Gods

Watch this video (in Spanish here) on Avocado Fruit Production. California is the biggest avocado producer nationwide; this delicious, versatile fruit arrived in the state in the 1890s. The demand for avocados has increased substantially over the last couple of decades. Nevertheless, avocado production faces many challenges.

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