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Don’t move firewood and pests

As autumn temperatures cool, many people like to warm themselves with a cozy fire.  When choosing firewood, natural resources experts ask that people use local firewood to avoid moving harmful insects and plant diseases into and around California.

“Buy firewood from a local source close to your home to prevent the spread of insects and diseases, such as the goldspotted oak borer, sudden oak death and emerald ash borer,” said Tom Scott, a UC Cooperative Extension specialist based at UC Riverside who studies these invasive pests.

“Firewood is one of the least-regulated natural resource industries in California,” said Scott, “but this is a situation where the university can play a critical role in changing behavior through research and education rather than regulation.”

Scott and his UC Cooperative Extension colleagues are working with the U.S. Forest Service, the California Firewood Task Force and other agencies to educate and discourage woodcutters, arborists, firewood dealers and consumers from transporting infested wood.

“Many people don’t realize that firewood can harbor harmful insects and plant pathogens. Moving around infested wood can introduce those pests and pathogens to new areas where they might take hold and could have devastating impacts to trees, our natural resources and local communities,” said Don Owen, California Firewood Task Force chair and CAL FIRE forest pest specialist based in Redding.

“Even wood that looks safe can harbor destructive pests,” cautioned Janice Alexander, UC Cooperative Extension sudden oak death outreach coordinator in Marin County.

For example, female goldspotted oak borers lay eggs in cracks and crevices of oak bark, and the larvae burrow into the cambium of the tree to feed so they may not be visible.

The goldspotted oak borer has killed more than 80,000 oak trees in San Diego County in the last decade and Scott hopes it can be contained in that region. The half-inch-long beetle is native to Arizona but not to California and likely traveled in a load of infested firewood, according to Scott.

In his research, Scott has found outbreaks of goldspotted oak borer 20 miles from the infested area, which leads him to believe movement in firewood is the most likely reason for the beetle leap-frogging miles of healthy oak woodlands to end up in places like La Jolla. In communities where people harvest local trees for firewood, oaks have remained relatively beetle-free, Scott said.

In addition to concealing goldspotted oak borer, firewood may harbor other destructive invasive species such as emerald ash borer or the pathogen that causes sudden oak death. Sudden oak death has killed more than a million oak and tanoak trees in 14 coastal California counties, from Monterey to Humboldt. The highly destructive emerald ash borer has been identified in Michigan, Indiana, Ohio and Illinois, but not California.

“Our best defense against the GSOB outbreak is the enlightened self-interest of Californians purchasing firewood,” Scott added.  “If you want to protect the oaks around your house, neighborhood, and nearby woodlands, make sure that you’re not buying wood that could contain these beetles.”

In a broader sense, buy firewood from reputable dealers, from local sources whenever possible – and try to make sure that the wood you buy has been properly seasoned and doesn’t contain pests.

Tips for buying oak firewood

• Don’t buy green firewood from unknown sources, it has the highest chance of containing pests and pathogens.
• Ask where the firewood originated. If it isn’t local, ask what precautions the seller has taken to ensure that the firewood is free of harmful insects and disease or consider buying from another local source.
• Wood should preferably be bark-free, or have been dried and cured for one year prior to movement.
• If you see D-shaped exit holes, be reluctant to buy unless you know the wood has dried for at least a year or longer.

For more information about the pests and diseases that threaten California’s oaks, visit these websites:

• GSOB.org
• firewood.ca.gov 
• suddenoakdeath.org

 

Sudden oak death disease has killed over a million trees in California.

Williamson Act cuts: Ranch land, critical conservation areas, at risk

State budget cuts have dramatically reduced funding for the Williamson Act, California’s conservation law that provides property tax relief for the owners of 15 million acres of rangeland and farms — preserving California’s prized open space.

New research reveals that if cuts continue and the act is eliminated, owners of ranchland plan to sell 20 percent of their total acres, according to William Wetzel and his co-investigators. Wetzel is a doctoral candidate in the UC Davis Department of Evolution and Ecology. The findings appear in the October–December 2012 California Agriculture, UC’s peer-reviewed research journal.

“In all, 37 percent of ranchers predicted they would sell some or all of their rangeland without support from the act,” Wetzel said. “Of those who would sell, 76 percent predicted buyers would develop the land for nonagricultural uses — suggesting that a significant amount of California’s open space could be lost.”

For smaller ranchers, tax relief often means the difference between a small profit and a loss, he and his colleagues found. They surveyed 700 ranchers who have Williamson Act contracts, randomly selected from act participants whose land comprises 15 million acres of working ranches and farms. Researchers asked ranchers for plans under a hypothetical elimination scenario.

Under the 1965 act, landowners promise to keep their property in agricultural use for set periods (originally, 10 years at a time). In exchange, they receive significant reductions in property taxes. The state reimbursed counties for most of the lost tax revenue until 2009, when the state virtually eliminated its contribution.

The scientists used both a written questionnaire and geospatial analysis to assess the impacts of eliminating the act. The geospatial analysis revealed that 72 percent of rangeland parcels enrolled in Williamson Act contracts contained habitat “important” or “critical” for statewide conservation goals, as defined by the California Rangeland Conservation Coalition. The Coalition designates 43 percent of enrolled parcels as “critical” for statewide conservation goals.

“Thousands of farmers and ranchers in 53 of California’s 58 counties have participated in Williamson contracts,” said Iara Lacher, co-author and UC Davis doctoral candidate. “California rangelands not only provide forage for cattle, they encompass unique ecosystems that provide habitat for threatened and endangered species. They also form most of the major drainage basins of the state, constantly filtering and purifying the water supply.”

Almost all of California's surface water, including drinking water for millions of people, passes through rangeland. This land -- grasslands, oak woodlands, wetlands, shrublands and desert -- accounts for 57 million of the state's 101 million acres, according to the California Department of Forestry and Fire Protection. Of that, most is used for grazing, 34 million acres. Grazed land itself consists of 18 million privately owned, and 16 million publicly owned, acres (the latter leased for grazing).

Rangeland accounts for more than 10 million acres under Williamson contracts; 5 million acres are prime farmland. Rangeland is considered “non-prime” because the soil is less fertile than that used for intensive agriculture. The distinction depends on the per-acre production potential of a parcel of land.

“Rangeland can provide many ecosystem services precisely because it is not put to intensive use, unlike suburban developments or irrigated agriculture,” Wetzel explained. At the same time, grazed land is the rangeland most at risk of conversion, with the current rate estimated to be 47,000 acres per year. Of ranchers surveyed, 72 percent considered the Williamson Act to be “extremely important” to their operations; 23 percent said they were likely or very likely to end their entire ranching enterprise if they lost this tax relief.

“California ranching is a vulnerable, low-profit industry,” said Dale Manning, study co-author and UC Davis doctoral candidate. “Of those surveyed, 38 percent lost money, 19 percent roughly broke even, and 42 percent made a profit. Of the ranches that made a profit in 2009, 70 percent made less than $10,000.”

Under the original Williamson Act program, contract-holding counties received annual subvention (financial assistance) payments from the state in proportion to their enrollment and to the productivity of the enrolled lands. These funds helped compensate for the tax revenue losses counties faced due to their participation.

Beginning in budget year 2008–2009, California drastically reduced subvention reimbursements to counties as part of a plan to phase out the program. In 2009–2010, California Governor Arnold Schwarzenegger cut state subvention funding to $1,000, essentially eliminating state support.

Before subvention payments were cut, state reimbursements to counties ranged from $5.2 million in heavily agricultural counties such as Fresno, Kern and Tulare to less than $12,000 in more urbanized counties such as Orange and San Bernardino. In 2010, in response to subvention payment loss, Imperial County ended its participation in the program, allowing contracts to expire countywide.

Under mounting budget deficits, a number of counties have placed a moratorium on new Williamson Act contracts because of uncertainty surrounding the future of subvention payments.

The research article, and the entire October–December 2012 issue, can be downloaded at http://californiaagriculture.ucanr.edu.

California Agriculture is the University of California’s peer-reviewed journal of research in agricultural, human and natural resources. For a free subscription, go to: http://californiaagriculture.ucanr.edu, or write to calag@ucanr.edu.

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WRITERS/EDITORS: To request a hard copy of the journal, e-mail crllopez@ucanr.edu.

MEDIA CONTACT: William Wetzel, Williamson Act study author, doctoral candidate, Department of Evolution and Ecology, UC Davis, (914) 552-7482, William.wetzel@gmail.com. Available on October 26 and after Nov. 1.

Dan Swezey, UC Davis doctoral candidate and study co-author, is an alternate contact when Wetzel is unavailable, (831) 345-6108, dsswezey@ucdavis.edu.

Rangeland data was taken from the California Department of Forestry and Fire Protection 2010 publication, California’s Forests and Rangelands: 2010 Assessment. http://frap.fire.ca.gov/assessment2010/pdfs/california_forest_assessment_nov22.pdf.

Selective dairy breeding could help prevent lameness, boost productivity

Dairies could increase their efficiency, reduce their carbon footprints and improve the health of their herds if they considered foot warts and other hoof ailments when they develop breeding plans, suggests a new study led by UC Davis researchers.

"Most dairy breeding programs select for milk production but the results of this study indicate that the cow's conformation, particularly in terms of hoof health, also should be considered," said Anita Oberbauer, professor and chair of the UC Davis Department of Animal Science and lead author of the study. The study is published in the October issue of the Journal of Dairy Science.

By reducing hoof-health problems through selective breeding, dairy producers could increase herd longevity, improve milk yield and reduce economic inputs and environmental impacts related to raising replacement heifers, the study concludes.

Oberbauer noted that lameness and hoof health are also animal welfare issues that can cause dairy producers to cull, or retire, cows early from their milking herds. As of 2011, an average of more than 40 percent of California dairy cows were culled annually, and lameness was one of the top three reasons for culling.

The 29-month study, conducted on three California dairies, correlated milk-production records with weekly observations of hoof health problems for more than 5,000 cows, including those that were visibly lame and those that were "dry," or finishing their milking cycle.

Recorded lameness-related hoof conditions included white line disease, sole ulcer, other claw horn lesions, foot rot and foot warts.

Foot warts were the most prevalent of the ailments, occurring in more than 17 percent of the monitored cows. The research also demonstrated a sizable genetic component to sole ulcer and foot warts, indicating that a breeding program directed at reducing hoof disease will likely lead to measurable improvements.

The study concluded that a breeding program that considers hoof-health traits would be unlikely to jeopardize the cows' milk productivity.

Oberbauer said that further study is now needed to identify the specific genes or DNA regions that are responsible for hoof-health traits.

UC Davis has helped to make California the nation's largest dairy state, contributing to better sanitation procedures, improvements in raw milk handling and quality, and innovations that have reduced the environmental impact of livestock waste. The J-5 vaccine alone, developed in 1988 by veterinary medicine faculty to prevent mastitis in dairy cattle, saves producers $11 million annually. Faculty research carried out at UC Davis also helped eradicate bluetongue virus in parts of the United States and rinderpest in much of Africa. Both diseases affect livestock.

Collaborating researchers on this study included Steven Berry, a Cooperative Extension dairy management specialist, staff researcher Janelle Belanger, alumna Rachel Goldrick and Professor Thomas Famula, all of the UC Davis Department of Animal Science; and Juan Manuel Pinos-Rodriguez of Instituto de Investigacion de Zonas Deserticas, Mexico.

The W.K. Kellogg Endowment and the University of California's Agriculture and Natural Resources division funded the study.

Zebra mussels and quagga mussels threaten California water systems

Some of California’s many introduced species — plants, animals, insects, and aquatic organisms — have marked impacts on ecological systems.

Invasive aquatic organisms can impact fish, shorebirds, marsh plants, and other wetland species, and alter functions of lakes, watersheds, floodplains, and coastal ecosystems.

Estuarine ecologist Ted Grosholz, a UC Davis professor and Cooperative Extension specialist in the Department of Environmental Science and Policy, is an expert on invasive species and addresses outreach education on zebra mussels and quagga mussels.

These two invasive, freshwater Eurasian mussels—zebra mussels and quagga mussels — could have a profound impact on California’s lakes and water distribution systems.

Both quarter-sized mussels showed up in California about six years ago. They attach themselves to water conveyance systems — pumps, pipes, dams, aqueducts, and fish hatcheries — and proliferate. According to Grosholz, “our drinking water and agricultural irrigation systems could be shut down quickly by these organisms.”

Los Angeles water districts are coping with the mussels, which are in Southern California watersheds, and reservoirs and canals of the Colorado River. The larval stage of the mussels disperses readily in water, so it gets moved around easily. There is tremendous concern about their potential spread into Lake Tahoe, and they have recently shut down a reservoir near San Jose. These mussels have cost the state tens of millions of dollars.

Zebra and quagga mussels pose a serious ecological threat in California. In the Great Lakes, where they became established 25 years ago, they have removed phytoplankton — a food source for juvenile fish — thereby impacting the food web. They have also concentrated the environmental contaminant botulism, resulting in massive kills of diving ducks and shorebirds.

Aquatic invasive species are moved long distances by ships — in ballast water, hulls and attached to ships’ surfaces. Within California they can be moved by recreational and fishing boats, trailers and other equipment.

“Once aquatic species are introduced, the cat is out of the bag — they spread easily, and they’re very difficult to control,” notes Grosholz.

Since the state doesn’t have the resources to adequately enforce zebra and quagga mussel control, areas such as Clear Lake and Fallen Leaf Lake are establishing local mandatory vehicle and boat inspection programs.

Grosholz works closely with resource agencies and other organizations to develop programs aimed at identifying and reducing the spread of invasive aquatic organisms. “It’s important to increase awareness of these species because they’re such a problem,” says Grosholz. “Their impact on ecosystems is big, and early control is very important.”

To read more about invasive aquatic species, including zebra and quagga mussels, see:

CA&ES Outlook magazine, pages 4–7

Quagga/Zebra Mussel Invasion, UC Cooperative Extension Coastal Resources

Quagga and Zebra Mussels, California Dept. of Fish and Game

Quagga and Zebra Mussel Prevention Program, San Luis Obispo County, California

Quagga and Zebra Mussel, Calif. Dept. of Boating and Waterways

How to design your landscape and eat it, too

Edible landscapes are growing like zucchini in the sun as more people recognize the health and economic benefits of designing their yards with pretty plants that taste good, too.

“Sales of fruits and vegetables have remained strong, even during this recession when sales of other plants have lagged,” said Ron Hoffman, owner of Morris Nursery in Riverbank,Calif., echoing the sentiments of many in the state’s nursery industry. “People enjoy growing their own produce and they want plants that do double duty.”

And when they choose brightly colored edibles — like, say, Neon Lights swiss chard or Bronze lettuce — they can have their landscape and eat it, too. But designing and maintaining an edible landscape is easier said than done. How do you know what plants to choose? What if one plant needs different soil and more water than its neighbor? How do you keep the cat from pooping on your produce?

The folks at the UC Cooperative Extension Master Gardener Program, with assistance from the California Center for Urban Horticulture at UC Davis, are answering those questions and many more at six, two-day, “train the trainer” workshops throughout the state. Funded by a two-year grant from the UC Agriculture and Natural Resources, the program teaches the art and science of edible landscaping to master gardeners who, in turn, will help train the rest of us.

“Before you install an edible landscape, you need to assess the site and the user,” said Missy Gable, program manager for the California Center for Urban Horticulture. “How much time do you have to devote to gardening? What are your harvest needs? We brought together experts from diverse fields such as landscape architecture, horticulture, food safety and water policy to provide an overview of what’s possible with edible landscaping.”

The workshops are inexpensive — $35 for master gardeners and $65 for industry professionals. In exchange for their reduced rate, master gardeners sign an agreement to teach two classes within three months of their training — one for fellow master gardeners and one for the public. Cheryl Buckwalter, a professional landscaper and executive director of EcoLandscapeCalifornia, attended an earlier workshop and called the experience “invaluable.”

“Today's landscapes need to work harder than ever,” Buckwalter said. “They need to be water and resource efficient, functional and aesthetically pleasing. The Edible Landscaping Workshop not only showed me how to design the multi-functional landscape of today by incorporating edibles, I also feel qualified to educate my clients, the public and other professionals.”

Will the workshops change the way people garden?

“As part of the project, we’ll be looking at that very thing,” said Pam Geisel, director of the UC Statewide Master Gardener Program and the project’s principal investigator. “We will evaluate the impact of train-the-trainer methodologies to determine whether participants adopt more productive, sustainable landscapes as a result of being trained or from training others.”

The benefits of edible landscaping are bountiful. Parents, for example, love exposing their children to both the joy of gardening and the value of healthy food. Farmers appreciate that more people realize produce doesn’t grow on grocery store shelves. But without a few pointers, it’s easy to err with edibles.  Sometimes, for example, our eyes are too big for our stomachs.

“Like me,” Gable said. “I’m a plant nerd. This summer I bought four varieties of zucchini because they were so cool. Believe me, no one needs four varieties of zucchini.”

No two yards or gardeners are the same and the course helps people customize their plan to meet their needs. Do you work 12-hour days? Maybe it’s better for you to help out at a community garden than plant too many edibles in your own back yard. Is your garden in full shade?

“Grow blueberries,” Gable said.

There is still room in three Edible Landscaping Workshops this fall: October 26-27 in Los Angeles; Nov. 2-3 in Fresno; and Nov. 30-Dec. 1 in San Luis Obispo. You can register and find more details at http://cchu.ucdavis.edu/events/edible/edible

 

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