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
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Art of the USDA
The USDA Pomological Watercolor Collection is one of the most unique collections in the Rare and Special Collections of the National Agricultural Library (NAL). As a historic botanical resource, it documents new fruit and nut varieties, and specimens...
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Figuring the Loss of Trees
UC Davis Ag Econ Department has put together a set of crop loss calculators in Excel. They are generic, but also specific to lemon and avocado. If you have had damage from the recent fire, take a look at them. At this point it may be...
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Fire in the Orchard
The very fact that avocados can be grown in hard to get to places means that the trees are also in areas that are subject to wildfire damage. Recently several hundred acres of avocado burned in the Fillmore/Santa Paula foothills. The fire was fanned by...
Riverside and San Diego County Newsletter
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| Volume 1, Issue 3 | Read our latest local newsletter |
| Volume 1, Issue 2 | Read our latest local newsletter |
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Topic in Subtropics Newsletter
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| Spring 2024 | Click here to read this issue of the Topics in Subtropics newsletter. |
| Winter 2024 | Click here to read this issue of the Topics in Subtropics newsletter. |
PEST ALERT - Black Fig Fly
(Diptera: Lonchaeidae: Silba adipata)
Invasive Fig Pest Recently Discovered in Southern California
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.
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.