Cooperative Extension Contra Costa
University of California
Cooperative Extension Contra Costa


Untreatable fungus giving almond producers pause

An airborne fungus from Europe, ganoderma adspersum, has been killing almond trees in the San Jaoquin Valley since it was discovered in the area five years ago, reported John Cox in the Bakersfield Californian.

The fungus rots wood from the inside out, usually weakening the trunk a ground level. 

Three kinds of ganoderma fungus infections were identified recently in California almond orchards; University of California researchers say 94 percent of the cases were of the adspersum variety.

"We are seeing those trees collapsing at 11, 12, 15 years old,” said UC Cooperative Extension orchard systems advisor Mohammad Yaghmour. The infections have results in the removal of orchards at less than half their typical 20- to 25-year life span.

Spraying for the fungal disease is ineffective. Yaghmour believes that in time researchers will identify a root stock that is resistant to the fungus.

A fallen almond tree that was weakened by Ganoderma fungus. (Photo: Bob Johnson)
Posted on Thursday, January 23, 2020 at 9:19 AM
Tags: almonds (30), ganoderma (1), Mohammad Yaghmour (3)

Non-native wild burros cause natural resource damage

The National Park Service has contracted with Peaceful Valley Donkey Rescue to humanely remove 2,500 to 4,000 burros in Death Valley National Park, a particularly challenging effort because the Bureau of Land Management, which manages adjoining land, does not consider the non-native equines a problem, reported Miranda Willson in the Las Vegas Sun.

The rescue organization rounds up the burros and puts them up for adoption.

A group of burros in Death Valley National Park. (Photo: National Park Service)

Experts say the burros damage vegetation near the park's desert springs, which support rare and endemic fish, plants, invertebrates and insects. They also compete with native grass-eating mammals — like endangered desert bighorn sheep — for food and access to increasingly rare watering holes, according to Laura Snell, livestock and natural resources adviser at the University of California Cooperative Extension.

“We've seen quite a bit of competition at watering holes throughout Nevada and northeast California,” Snell said. “All of those animals need water, and there's maybe only one watering hole available year-round.”

Executive director of Peaceful Valley Donkey Rescue Mark Meyers said wild burros are a part of American history that people can experience and preserve by adopting them.

“We used them for the Spanish Trail, we used them for Catholic mission systems, we used them for the railroad, we used them for mining. We used them for all these capacities, and then we said, ‘We don't need them anymore,' ” Meyers says. “These animals built our country, yet they're the ones that aren't supposed to be here.”

Posted on Monday, January 13, 2020 at 9:25 AM
Tags: burros (1), Death Valley (1), Laura Snell (2)
Focus Area Tags: Natural Resources

UCCE promotes CalFresh to increase access to healthy, local food

CalFresh Food signage at the market

A UCCE-led work group promoted the use of EBT/CalFresh and other farmers' market incentives for families to purchase more fruits and vegetables at farmers' markets, resulting in a 30% increase in EBT/CalFresh customers.   The...

Posted on Friday, January 10, 2020 at 11:52 AM

Turn food and garden waste into rich fertilizer with worms

UC Master Gardeners in Stanislaus County presented an all-natural, sustainable solution to disposing garden and food waste during a session for the community on worm composting, reported John Holland in the Modesto Bee.

All it takes is an 18-inch deep bin, equipped for drainage, and a supply of red worms. Provide the worms a substrate that contains a mix of high carbon materials - like shredded paper, dry leaves or sawdust - and kitchen scraps - such as fruit and vegetable cores and peels, leftover grains and coffee grounds. A few months later, the worms will have transformed the contents into a rich organic fertilizer ready to be applied to garden plants.

"It's a great fertilizer," said UC Master Gardener Dennis Lee. "It's very inexpensive for you to produce. You can do it indoors. There's very little odor - actually, no odor.

A red wiggler worm moves through substrate during composting process. (Photo: Holger Casselmann, Wikimedia Commons)

Learn more:

Orange County UC Master Gardeners created a video series on worm composting 

Vermicomposting - Composting with Worms, from San Joaquin County Master Gardeners 

Posted on Monday, January 6, 2020 at 9:44 AM

Integrated aquatic pest management shows promise

Carolynn Culver, a research scientist at UC Santa Barbara and an California Sea Grant extension specialist, is researching whether native sunfish can be used in place of toxic chemicals to reduce invasive mussel larvae and other pests in Southern California lakes and reservoirs, reported Sonia Fernandez in the USCB online magazine Futurity.

Quagga mussels at different stages of development. (Photo: California Department Fish and Wildlife)

Quagga and zebra mussels are two of the most devastating aquatic pests in the United States. The small freshwater mussels grow on hard surfaces such as water pipes, and can cause major problems for water infrastructure. First appearing in North America in the 1980s, and in California in 2007, mussel management with chemicals has been shown to impact water quality.

“Commonly used mussel control methods are problematic for San Diego reservoirs since they are primary water supply reservoirs,” said study coauthor Dan Daft, a City of San Diego water production superintendent and biologist.

A pipe clogged by an accumulation of invasive mussels. (Photo: Mussel Prevention Program, San Luis Obispo)
The researchers found that when one species of sunfish, bluegill, was penned up in an area where mussels occur, it could significantly reduce microscopic larvae and newly settled young mussels on surfaces within the pen, and on the pen itself. This method could be one key piece of an integrated pest management strategy, and provides a nonchemical method for targeting early life stages of the mussels, which are hard to detect.

In another study aimed at protecting water from toxic chemicals, Culver worked with UC Cooperative Extension advisor emeritus Leigh Johnson to study hull cleaning practices that can be alternatives for using copper-based paints, which leach copper into water.

The team showed that frequent, minimally abrasive, in-water hull cleaning was effective and did not cause an increase in fouling as reported for other hull cleaning practices. Results from the study, along with other research findings, informed the development of an integrated pest management framework that boaters can adapt to different regions and specific needs.

“It's not a one-size-fits-all approach — it's adaptive,” Culver said. “Boaters can tailor it to local environments, regulations and boating patterns, and it can be applied in areas where toxic paints have been restricted, as well as where they continue to be used. It can help to keep boat hulls clean, while reducing impacts on water quality and transport of invasive species — three issues that often are not considered together.”

 Read more about UCCE quagga and zebra mussel research and extension.

Posted on Thursday, January 2, 2020 at 10:33 AM
Focus Area Tags: Environment

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