- Author: Chris M. Webb
Caused by the bacterium Erwinia amylovora, fire blight is a common and frequently destructive disease of pome fruit trees and related plants.
Symptoms commonly appear in spring. The first sign is usually a watery, light tan ooze that leaks from cankers. After being exposed to the air, the ooze darkens and leaves streaking on branches or trunks. Other signs of infection are petal fall, flower stem wilt, and the blackening and shriveling of flowers, shoots, and/or young fruit.
As the disease progresses, the pathogen spreads into the wood. The infected wood tissue can become sunken and cracks often develop in the bark around the infected areas.
Ideal conditions for infection, disease development and spread of the pathogen are rainy or humid weather with daytime temperatures from 75 (degree sign) F to 85 (degree sign) F.
Home Gardeners can learn more about fire blight in UC IPM’s Pests in the Gardens and Landscapes: Fire Blight publication. Subjects include: identification and damage; life cycle; and management.
Commercial growers can find fire blight information by crop on UC IPM’s Agricultural pest page.
- Author: Chris M. Webb
After the recent HLB detection in Los Angeles County, many people have been contacting our office. We would like to take this opportunity to remind you about the Ventura County ACP-HLB Task Force.
The Task Force, founded January 2010, “is dedicated to the early detection and swift eradication of this invasive pest, and to preventing the disease it transmits from devastating Ventura County citrus.”
To allow for quick exchange of information and open communication, the Task Force is on Facebook. The information and resources available on their page are extensive.
Recently added resources include a free smart phone app from the USDA designed to help report suspected citrus diseases, including HLB.
- Author: Chris M. Webb
While the Asian citrus psyllid/HLB pest-disease complex has received a lot of press lately, another deadly pest-disease combination has been found in Los Angeles County.
Tea Shot Hole Borer (Euwallacea fornicatus) is a vector for the Fusarium fungus. A native from Asia, this beetle is very small. Females are between 1.8 to 2.5mm (0.07-0.1 inch) long. Males are even smaller at 1.5mm (0.05 inch).
In addition to avocado trees, this insect is a serious pest of tea in Sri Lanka and India. In California, The Tea Shot Hole Borer was first reported on black locust (Robinia pseudoacacia), Lychee (Litchi chinensis), Box elder (Acer negundo), but there were no reports of fungal damage.
What to do:
- Look for a single exit hole with surrounding white powdery exudate.
- Scrape off the bark layer around the infected area to see the canker.
- Follow the gallery to look for the beetle (may or may not be present).
- Avoid movement of infested avocado wood out of infested area.
- Look for other hosts (Castor beans plant, Black locust, Lychee, and Acer) showing symptoms of the beetle/disease.
- Because the beetle tends to colonize both live and new dead wood, chip the dead wood within the grove and cover with a tarp for at least a week to prevent further beetle colonization.
- Sterilize tools to prevent spread of the disease with either 25% household bleach, Lysol (add symbol) cleaning solution, or 70% ethyl alcohol.
For more information please see the Fusarium dieback on California Avocado trees vectored by the Tea Shot Hole Borer Pest Alert developed by researchers at UC Riverside. The flyer is available in English and in Spanish.
- Author: Chris M. Webb
The first Small Farm News of 2012 is ready for viewing! As always this newsletter is full of relevant and practical information to assist small-scale farmers and ranchers.
Topics in this issue are:
- Workshops to prepare growers for food safety
- Building statewide support for California agritourism
- Selling wholesale at a farmers market
- Tips for growing, selling organic
- CSA operators offer tips
- How to identify ‘snake-oil’ products
- Pedro Ilic Award honors Paul Vossen
The newsletter can be found on this page of the UC Small Farm Program website.
- Author: Chris M. Webb
UC Farm Advisor Oleg Daugovish will hold an Irrigation field day Thursday, April 19 from 9:00 am to 11:15 am.
Scheduled topics include:
- Update on conditional waiver and requirements for irrigated lands in Ventura County
- Evaluation of three differing irrigation regimes in California strawberry
- Salts and soil analyses in strawberry beds under different irrigation regimes
- Soil test results interpretation and corrective management
- View experiment plots onsite
VCALIG educational credits have been requested from the Los Angeles Regional Water Quality Control Board.
There is no cost to attend. If you have questions, require translation into Spanish, or to register please contact Oleg Daugovish at 805.645.1454 or odaguovish@ucdavis.edu. More information can be found on the agenda.
In the event of rain, the meeting will be held at the UCCE Conference Room located at 669 County Square Drive in Ventura.