Recently our office has received many calls about bee swarms. These calls are typical at this time of year.  Each swarm can contain 5,000 to 20,000 bees.

Understandably bee swarms can cause uneasiness to residents unfamiliar with honey bees. While the swarms might seem frightening, the common honey bee is extremely docile. Unless they feel threatened they are unlikely to react defensively.

Swarming bees are in search of a new home. Honey bees prefer dark cavities with an easily defendable entrance at least 9 feet from the ground. Hollowed out trees are ideal sites, but other favored sites  include: inside walls of houses, in or around chimneys, in outbuildings, fences, shrubs, water meters, utility boxes, barbecue grills, or under decks.

To learn more about honey bee swarms and hives, please see UC’s Removing Honey Bee Swarms and Established Hives.

Topics include:

• What is a bee swarm?
• Damage
• Swarm clusters
• Preventing establishment of a colony in your home
• Removing established colonies from your home
• Preventing future invasions
• Finding professionals to assist with colony extractions

Swarm of honey bees, Apis mellifera, on a lemon tree limb. Photo by David Rosen.

Over the last 10 years, the Goldspotted Oak Borer (GSOB) has killed approximately 80,000 oak trees in San Diego County – including many large trees that were hundreds of years old.

To date GSOB has caused significant economic, ecological, cultural, and aesthetic losses in San Diego County.  The costs of dead tree and infested wood alone is staggering.

GSOB (Agrilus Auroguttatus) is an invasive insect in California. Because it is a non-native pest there are not natural defense mechanisms to keep this insect in check.  There is concern among experts that GSOB will continue to move north through California. Susceptible oak species are: coast live oak, California black oak, and canyon live oak.

It is highly suspected that GSOB entered California in firewood. GSOB larvae can live under the bark of dead oaks for over a year before exiting as adults. It is likely GSOB has spread so quickly in San Diego County via firewood movement. Because of this, it is extremely important to be mindful of where your firewood comes from. The movement of infested firewood could easily establish this destructive pest throughout the state.

To learn more about GSOB, or to get involved in preventing its spread, please see the gsob.org website.

And remember, to protect California’s Forest – Buy and Burn Local Firewood! Don’t move it around!

Oak trees in urban and natural settings throughout California are at risk of dying from the GSOB. Please do what you can to limit the spread of this destructive pest. Photo by K. Jones.

The 2012 California Citrus Conference will be held October 10-12 in Porterville. This event is organized by the Citrus Research Board (CRB) and will include presentations, demos, and exhibitors.

Topics will include:

• ACP/HLB
• Pests
• Diseases
• Organics
• Irrigation
• Nutrition

Demonstrations and displays will include:

• ACP tracking and mapping
• Spray demonstrations
• Irrigation technologies
• Sensory evaluation lab

For more information please call the CRB at 559.738.0246 or email them.

The California Citrus Conference will have much information for citrus growers. Photo of navel orange bloom by Jack Kelly Clark.

The Natural Resource Conservation Service (NRCS) works extensively with the nation’s farmers and ranchers to protect soil, water, air, plant, and animal resources while meeting production goals.

Working with agricultural producers allows NRCS to promote conservation practices approximately 1.4 billion acres of the privately held land in the United States. About 92 million acres of land in our country is tended by home gardeners. In an effort to promote conservation on these lands, NRCS has partnered with other organizations to produce, Backyard Conservation: Bringing Conservation From the Countryside to Your Backyard.

This full-color and informative online resource highlights 10 conservation activities that can be used in your backyard, shared spaces, and public places too.

Topics include:

• Trees add beauty and so much more.
• Trees, shrubs, and other plants can provide homes and food for wildlife.
• A backyard pond will likely become the focal point for all your backyard conservation.
• Wetlands filter excess nutrients, chemicals, and sediment and provide habitat for a host of interesting creatures.
• Composting turns household wastes into valuable fertilizer.
• Mulching cools, protects, and enriches the soil.
• Apply only those nutrients the plants can use. (See our previous post on soil test kits to help you get accurate test results.)
• Terracing makes flower and vegetable gardening possible on steep slopes.
• Drip irrigation and other water conservation practices can save water and money.
• Early detection and treatment of pests means a healthier growing environment.

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.

Blackening of the young fruit and tan droplets of ooze are typical of a fire blight infection. Photo by Jack Kelly Clark.