“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:
- Author: Janet L. White
- Editor: Pamela Kan-Rice
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.
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.
- Author: Pat Bailey, UC Davis News Service, (530) 752-9843, pjbailey@ucdavis.edu
"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.
- Author: Jeannette E. Warnert
California almonds are on a roll. In the last 20 years, scientific discovery and grower ingenuity have nearly doubled almond per-acre productivity. A good yield in the 1980s was 1,400 pounds per acre. The average yield for 2011 was 2,670 pounds of shelled almonds per acre.
Forty years ago, California farmers produced less than 100 million pounds of almonds on about 200,000 acres of almond orchards. Mechanization, improved irrigation efficiency, advances in insect and disease management, pruning research and fertilization studies have fueled explosive growth in the industry. Farmers in California’s Central Valley now tend 760,000 acres of almond trees, producing about 2 billion pounds of shelled nuts a year. The crop, which represents 100 percent of U.S. almond production and 75 to 80 percent of world production, was valued in 2011 at $3.87 billion, surpassing table, wine and raisin grapes, which were valued at $3.86 billion.
“Even with this record production, we have more demand than we have supply,” said Bob Curtis of the Almond Board. “The driver behind that is nutrition studies that show almonds are a healthy food and snack.”
A tremendous amount of UC research is behind the California almond success story, said Bruce Lampinen, UC Cooperative Extension specialist in the Department of Plant Sciences at UC Davis, an expert in almond canopy management.
“Higher density plantings of almonds and a trend towards less pruning, and improved water management have led to much higher yields,” Lampinen said.
Many almond growers have replaced flood irrigation with micro-sprinkler or drip irrigation, said Larry Schwankl, UC Cooperative Extension specialist in the Department of Land, Air and Water Resources at UC Davis. These irrigation systems increase the precision of water and fertilizer application. Over the years, UC Cooperative Extension advisors and specialists established demonstrations of micro-sprinkler and drip systems in many parts of the Central Valley and reached out to farmers to show how they could be managed to optimize production.
“Twenty years ago, we simply guessed at the amount of water that the trees needed and we applied it on a calendar basis,” said Joe MacIlvaine, president of Paramount Farming Company in Kern County, one of the state’s largest growers of almonds, pistachios and pomegranates. “Today, we are delivering water and nutrients directly to the root zones when they are needed.”
Two decades ago, a granular form of nitrogen fertilizer was generally applied to almond orchards in the fall to allow winter rain and irrigation to move it into the soil for use by the trees in spring and early summer. Nitrogen use efficiency was believed to be about 40 percent. Now, nitrogen fertilizer is applied through the irrigation system during the growing season, when the tree needs it.
“Today, our nitrogen use efficiency can be as high as 85 percent,” said Blake Sanden, UCCE advisor in Kern County, an irrigation expert. He and Patrick Brown, professor in the Department of Plant Sciences at UC Davis, have conducted nitrogen trials in almonds with Paramount Farming.
“When you increase the conversion of applied nitrogen fertilizer to higher crop yield, there is significantly less potential for nitrogen to leach below the rootzone and contaminate groundwater,” Sanden said. “But each field is unique and requires site-specific management to achieve these high levels of efficiency.”
Another area where UC research has led to significant crop yield growth is in canopy management and tree spacing. Research by Mario Viveros, UCCE advisor emeritus in Kern County, and other scientists showed that a tendency among growers to over prune was taking a toll at harvest time.
“A lot of farmers who are now growing almonds had experience with fresh fruits, where you do need to prune to get light on the fruit for good color. In almonds more canopy generally means more yield,” Lampinen said. “Today, most almond growers only prune when branches are growing in the way of tractors or other equipment.”
UC research also found that orchards planted with traditional wide spacing between the trees weren’t making the most efficient use of sunlight on the farms. Older orchards had 60 to 70 trees per acre. Today, almond orchards are planted at an average density of about 110 trees per acre based on results of UC research.
However, studies have also shown that crowding still more trees into orchards triggers diminishing returns. In almond production, the nuts are shaken from the trees to dry on the ground before they are harvested.
“If the orchard floor becomes too shaded by trees planted too densely, the orchard floor temperature and humidity become optimal for growth of pathogens that could become a food safety problem,” Lampinen said. “You want enough sunlight to hit the orchard floor to reduce potential pathogens, like salmonella.”
MacIlvaine acknowledged the role of UC Cooperative Extension in helping the almond industry achieve the production milestone in 2011.
“The University of California has been a wonderful partner in improving our farming practices,” he said. “The whole system is not only more efficient, but more sustainable at the same time.”
Hear more of MacIlvaine's comments in the video posted below:
- Author: Jeannette E. Warnert
Follow the event in real time from 5 a.m. to 12 noon Pacific Time on Twitter using the tag #whgarden.
White House Social is a series of in-person meetings of people who engage with the White House through social media, including Twitter, Facebook and Google+. Hayden-Smith has followed Barack Obama, Michelle Obama and the White House on Twitter since Obama's election in 2008. She won the invitation after entering a contest that asked contestants to describe in 140 characters why they wanted to visit the White House garden.
"I'm really excited to be part of this,” said Hayden-Smith, who is also a UC Cooperative Extension advisor in Ventura County, specializing in 4-H youth, family and community development. "The fact that the Obamas are cultivating a food-producing garden on the grounds of the White House says really wonderful things about our country. The First Family is showing its concern about the health of Americans and reducing childhood obesity. That's something we at UC Cooperative Extension care a great deal about.”
Hayden-Smith Tweets as "Victory Grower” (@victorygrower) a persona she created to reflect her interest in a national revival of the Victory Garden movement, in which increasing food production was considered vital to bolstering national security by creating a more secure food supply.
"It's a different 'victory' now, but many of the goals are the same," Hayden-Smith said. "Gardens connect people with food and food production. Food is fundamental. It's what everyone shares in common. As we are entering a more challenging era of increased population and pressure on resources, it is vital for people to understand how to cultivate food.”
Hayden-Smith travels to Washington D.C. on Wednesday, Oct. 17. On Thursday, she and her colleague Rachel Surls (@rachelsurls), UCCE advisor in Los Angeles County, will tour urban garden projects in the nation's capital. They will be Tweeting about their tour on Thursday afternoon using the tag #urbanag.
Though not an official part of White House Social, Surls will have a brief tour of the White House Kitchen Garden on Friday. She will Tweet on Friday using the tag #whgarden.
Surls and Hayden-Smith are joining with UC Agriculture and Natural Resources to promote urban agriculture in California, an effort that is expected to generate multiple benefits. Gardening provides a way for people to be physically active, to improve food access, to increase fruit and vegetable consumption and to reconnect people with agriculture.
Following are background articles related to Victory Grower and urban agriculture efforts:
- Victory Gardens: A boon in hard times
- Summon us to service
- Kitchen table memories
- Urban Agriculture: A good model then, a good model now
- On the future of food
- UC helps you design your landscape and eat it, too
- Outlook: UC's land-grant mission fuels nation's growth, prosperity
- Setting agricultural science strategy in tumultuous economic times
