Cooperative Extension San Joaquin County
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Cooperative Extension San Joaquin County

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Agricultural water conservation — a serious look

With this latest set of storms replenishing California’s snowpack and water levels in reservoirs, rivers and streams, it may be hard to think about water conservation issues. But this is a still a semi-arid state, so it is always prudent to prepare for droughts.

So where can we save the most water? Farming in California depends on irrigation, so agriculture seems the largest potential source for cost-effective water savings in the state. Although agriculture’s share has been declining, it still accounts for roughly 75 percent of all human water use, compared to 25 percent for urban uses.

The recent book, Managing California’s Water: From Conflict to Reconciliation, examines agricultural water conservation extensively and points out the complexity of this issue.  The book’s findings are based on scientific and economic research and field experience in California and worldwide.

Much agricultural water is still devoted to relatively low-value crops:  In 2005, over 60 percent of “net” water use in the agricultural sector – the amount consumed by crops – was for irrigation of pasture and field crops such as alfalfa, corn, rice, and cotton, which generated only 14 percent of crop revenues. These statistics imply significant potential for reducing farm water use without incurring overwhelming consequences for the state’s economy.



Contrary to popular understanding, however, improving on-farm irrigation efficiency is usually a poor way to achieve real agricultural water savings.  Real conservation usually requires shifting to crops that use less water or reducing crop production, such as by fallowing farmland. This is because much of the irrigation water applied when farmers use “inefficient” techniques like furrow irrigation is returned to streams or aquifers, where it becomes available for reuse.

This is the international scientific consensus on irrigation conservation, from studies worldwide. Most groundwater recharge in California’s Central Valley is from irrigation runoff and percolation. This recharge helps to replenish depleted aquifers and serves as a significant source of supply during drought. Only a few areas in California, such as the Imperial Valley, can save large amounts of water by adopting more efficient irrigation techniques. In such areas, the excess irrigation water flows into saline water bodies or contaminated aquifers, where it is unavailable for reuse, so reducing runoff generates real water savings.



Even though improving irrigation efficiency usually does not produce significant real water savings, it can provide economic benefits for farmers.  Farmers usually pay for the amount of water they apply to their fields, not the amount consumed by crops.  When farmers face limited supplies, they often have an incentive to adopt more efficient techniques, such as drip irrigation, to make use of every possible drop on their farms.

These techniques, often combined with laser leveling of fields and more precise doses of fertilizers and pesticides, can improve crop productivity and quality. In recent decades, many San Joaquin Valley farmers have made such changes, which have enabled them to plant greater acreages of higher-value fruit, nut and vegetable crops.

Improving irrigation efficiency also can provide environmental benefits. For instance, agricultural runoff sometimes contains harmful salts and other chemicals, and more efficient irrigation can help reduce these discharges.  This is another reason for the rise in more efficient irrigation techniques on the west side of the San Joaquin Valley, where farmers are required to limit runoff of selenium, a toxin to wildlife. Similarly, by reducing diversions, irrigation efficiency may allow higher streamflows on particular stretches of rivers, improving conditions for aquatic life.

Although counterintuitive, more efficient irrigation techniques also can increase water consumption. By allowing farmers to farm their fields more intensively and to expand irrigated acreage with the water they “save,” techniques like drip irrigation can increase net farm water use within a region, thereby reducing groundwater recharge and nearby streamflow.  Conservation-oriented policies that neglect this possibility can exacerbate groundwater overdraft, as studies from New Mexico to Yemen have shown.

What is the right policy to encourage effective agricultural water conservation? It depends on the objective. To encourage real water savings, the best policy is to let market forces work. Water markets are a flexible and efficient way to encourage farmers to create real water savings for higher-valued uses. California needs to improve the ability to buy and sell water, by reducing state and local barriers, to give farmers better price signals. To reduce polluted agricultural runoff or improve streamflows in some areas, the best policy is to adopt regulations that directly address pollution discharges and instream flows, and allow farmers to choose the most cost-effective way to meet these requirements.

In contrast, policies that impose particular irrigation technologies, or even ban specific crops, are likely to impose higher costs on farmers and society, while failing to save real water. Given the immense variety and variability of conditions in California, rigid regulatory policies to promote agricultural water conservation seem more likely to create more controversy and increased social cost than usable water savings.

Agricultural water conservation is an important part of California’s water future. But simplistic notions of water conservation threaten to mislead California’s water policy debates by presenting the false claim that water saved from on-farm use is necessarily water saved to the system. It is time to take water conservation seriously. In doing so, we also must undertake water conservation scientifically, rather than rhetorically.

(This post is excerpted from the California WaterBlog—“Taking Agricultural Conservation Seriously”.)

Posted on Wednesday, March 30, 2011 at 8:41 AM
  • Posted By: Trina Wood
  • Written by: Jay Lund, Ellen Hanak, Richard Howitt, Ariel Dinar, Brian Gray, Jeffrey Mount, Peter Moyle, Barton “Buzz” Thompson

UC offers webinar series on community forests

If you are passionate about a forest near you then you may want to tune into the UC Cooperative Extension webinar series on Community Forests.  The webinars will begin at 6:30 p.m. Pacific Standard Time on April 7 with additional programs on April 13, 20 and 27. Participants may also want to take part in related field trips to Arcata Community Forest, Usal Redwood Forest, Tahoe-Donner and Weaverville Community Forest.

Community forests are forested lands that are managed to produce what people value. Forests may be valued as a source of timber for lumber, clean water, wildlife habitat, recreational purposes or for all of these benefits in combination.

The webinar series aims to present an overview of community forestry as it is currently being practiced in California. The intended audience is natural resource managers, environmental and forest activist groups, residents of forested regions who might benefit from a community forest approach in their areas and the general public concerned with forest management.

This program is a collaborative effort of the University of California Cooperative Extension and the Northern California Society of American Foresters, with funding support from the USDA Forest Service and the University of California.

Additional information and a link to registration are available at http://ucanr.org/community_forests.

UC collaborators on the project are natural resources advisors Mike De Lasaux, Susie Kocher, Gary Nakamura and contractor Richard Harris.

A webinar series and field trips will educate the public on community forests.
A webinar series and field trips will educate the public on community forests.

Posted on Thursday, March 24, 2011 at 8:26 AM
Tags: forest (12), Gary Nakamura (1), Mike De Lasaux (4), Susie Kocher (14)

White-nose syndrome takes devastating toll on bats

White-nose syndrome, a horrific disease that has killed millions of bats on the East Coast since its identification in 2006, is spreading fast across the United States, warns Rachael Long, UC Cooperative Extension farm advisor for Yolo County. She dreads its arrival in California.

This disease is caused by a fungus that grows most noticeably on a bat’s muzzle, coating it in a white powder, hence the name "white-nose." It primarily affects hibernating bats by causing them to be more active, according to Long.

"As a result they wake up more often during the winter, burn up fat reserves, and die of starvation," Long said. Where the disease is occurring, bats that were relatively common are now rare.

"Like a tsunami on a quiet beach, white-nose syndrome is expected to strike California in the next couple of years," Long said. "With 25 species of bats in our state, the potential loss in the abundance and diversity of bats could be devastating."  

Bats are extremely important in our environment. They are voracious predators of insects, often consuming their body weight in insects each night. As a result, they are important allies to farmers, helping to reduce the numbers of insects that damage crops and providing important ecosystem services in agricultural landscapes.

Currently no one knows where white-nose syndrome came from or how to control it. The disease first showed up in New York in 2006 in a cave that is a popular tourist destination, so it may have been introduced by a foreign visitor.

The hope is that enough bats have a strong enough immune system to survive the disease to repopulate the landscape before colonies go extinct. Likewise, researchers hope that the fungus will not adversely affect migratory colonies, that is, those bats that spend the winter in warmer climates and return to more temperate regions in spring and summer. The fungus favors cooler conditions so it may primarily impact bats that hibernate. California is home to both types of bats. For example, the Mexican freetailed bats migrate, but big brown bats hibernate.

Long suggests a number of ways that one can help bats and the white-nose syndrome crisis, including the following:

  • Report unusual late-winter bat behavior (for example, bats flying during the daytime) or unexplained bat deaths to your state wildlife agency.
  • Adhere to state, federal and local cave advisories and closures to help prevent the transmission of white-nose syndrome. Even though bats carry the fungus, people can also move the disease around and in greater distances than bats.
  • Share with family and friends the benefits of bats and information about the white-nose syndrome crisis.
  • Encourage state and federal legislators to allocate funding towards the effort to understand and fight white-nose syndrome.
For more information about white-nose syndrome, visit the U.S. Fish and Wildlife Service’s website at www.fws.gov/WhiteNoseSyndrome or the Bat Conservation International website at http:www.batcon.org.

For more information about bats, see Long's research articles published in California Agriculture journal: "Well-placed bat houses can attract bats to Central Valley farms" and "Bats feed on crop pests in Sacramento Valley."

The photo above of the little brown bat with white fungus on his nose is courtesy of Ryan von Linden of the New York Department of Environmental Conservation. The U.S. Fish and Wildlife Service has this photo and other photos showing symptoms and the effects of white-nose syndrome at http://www.fws.gov/WHITENOSESYNDROME/photos.html.

Posted on Wednesday, March 16, 2011 at 8:11 AM

Loss of Williamson Act would threaten wildlife habitat

California’s premier farmland protection tool – the Williamson Act – is on the state’s budget-cutting chopping block and with it critical habitat needed for conservation.

A UC Davis study completed by a team of graduate students working with rangeland watershed specialist Ken Tate and other faculty found that 43 percent of the 10 million acres of “non-prime” land in the program, used primarily for cattle grazing, is also critical for statewide conservation goals. Conservation status was determined by the California Rangeland Conservation Coalition, a voluntary partnership between ranchers, environmentalists, government agencies, and others working to preserve and enhance the state’s rangeland areas.

For nearly 50 years the Williamson Act has provided private landowners with tax breaks in exchange for an agreement to keep land in agricultural or open space use for a specified period of time. The state compensated counties for the reduced property tax revenue but cut these subsidies in 2008 and again in 2009. Legislation passed in October (Assembly Bill 2530) allows counties to voluntarily implement modified contracts for reduced terms but does not ensure continuation of the Williamson Act beyond 2015.

To understand how loss of the Williamson Act would affect ranchers and the environment, the researchers surveyed 700 members of the California Cattlemen’s Association in 2010. Their findings confirmed what many in the industry already know: ranching is a low-profit industry. Seventy percent of surveyed ranchers made less than $10,000 in 2009 and less than half reported making a profit. Seventy-two percent of the ranchers surveyed consider the Williamson Act to be “extremely important” to their operations.

Survey results also show that loss of Williamson Act funding at the state level would put critical habitat at risk for development. Forty-two percent of the surveyed ranchers said they would sell some or all of their rangeland without the tax relief. Fifty-six percent of the ranchers predict their sold land would be developed for non-agricultural uses.

“California’s rangelands provide clean drinking water, wildlife habitat, open space, and sequester carbon among many other critical ecosystem services,” Tate says. “We need tools such as the Williamson Act to conserve this important landscape.”

Study authors include doctoral students Sarah Myhre, Iara Lacher, Will Wetzel, Dale Manning, and Dan Swezey. They were participating in a collaborative project for an “IGERT” traineeship focused on rapid environmental change. The program is funded by the National Science Foundation. A concise policy brief on the survey was published in October 2010 and includes an illustrated map of the areas that could be affected by the demise of the Williamson Act. The policy brief and additional information about the program is available online at http://reach.ucdavis.edu/programs/williamsonact.html.

Posted on Monday, March 7, 2011 at 10:14 AM
Tags: Ken Tate (4), rangeland (14), wildlife (24), Williamson Act (1)

Show me the honey

“Going green” means buying local honey, say honey bee experts at the University of California, Davis.

“It’s not only supporting the local beekeepers in our flagging economy, but imported honey can be problematic,” said bee breeder-geneticist Susan Cobey. “When you buy imported honey, you don’t always know what you’re getting. The ‘honey’ could be a mixture of corn syrup and water, or blends of honeylike products. It could contain pesticides or antibiotics. It could be mislabeled or from a different country or floral source than indicated on the label.”

“Also,” Cobey said, “you don’t know how it’s been treated after bottling. Heated honey, for example, breaks down the enzymes and causes the honey to lose flavor.”

Some unethical honey importers illegally mark their products or route them through other countries to avoid paying tariffs or to avoid public health safeguards.

A recent investigative report published in the Seattle Post-Intelligencer found that “big shipments of contaminated honey from China are frequently laundered in other countries — an illegal practice called ‘transshipping’ — in order to avoid U.S. import fees, protective tariffs or taxes imposed on foreign products that intentionally undercut domestic prices.”

“In a series of shipments in the past year, tons of honey produced in China passed through the ports of Tacoma and Long Beach, Calif., after being fraudulently marked as a tariff-free product of Russia,” according to the investigative report.

Investigative reporter Andrew Schneider found that laundered Chinese honey is often shipped into the United States from Australia, Cambodia, Hong Kong, India, Indonesia, Malaysia, Mongolia, Russia, Singapore, South Korea, Taiwan, Thailand and Vietnam, then relabeled as coming from there instead of China.

The news is not new, and neither are the "stings." The Associated Press recently related that "a Chinese business agent for several honey import companies was arrested in Los Angeles Tuesday (Feb. 15) on federal charges filed in Chicago for allegedly conspiring to illegally import Chinese-origin honey that was falsely identified to avoid U.S. anti-dumping duties. The charges resulted from an investigation conducted by U.S. Immigration and Customs Enforcement's (ICE) Homeland Security Investigations (HSI)."

The business agent was accused of "conspiring between 2004 and 2006 to illegally import Chinese-origin honey that was falsely identified as originating in South Korea, Taiwan and Thailand to avoid U.S. antidumping duties."

The fact is, the United States doesn't produce enough honey to supply the demand. And due to the lower price, U.S. consumers may reach for the imported honey instead of the locally produced honey.

"Currently U.S. honey producers can supply about half the honey consumed in the U.S.  annually,” said Extension apiculturist Eric Mussen of the UC Davis Department of Entomology, who writes and publishes the bimonthly newsletter, from the UC Apiaries. “We have to import substantial amounts of honey. If the foreign sources lower their prices far enough, our honey producers can't sell their honey at competitive, above cost-of-production prices. To maintain our market, we cannot allow low-cost honey to slip past the tariffs now in place to keep domestic sales moving."

The UC Davis bee experts expressed concern that antibiotics banned in the United States are used to treat diseases in bee hives in other countries, and then the honey is shipped here. For example, beekeepers in China sometimes use an animal antibiotic, chloramphenicol, in their hives. When humans ingest the honey, it can cause serious illness and sometimes death.

Show me the money? Or show me the honey?

Honey Extraction
Honey Extraction

FRAME OF HONEY COMB ready for the extraction process at the Harry H. Laidlaw Jr. Honey Bee Research Facility at the University of California, Davis. UC Davis doesn't market honey, but the bee experts at the Laidlaw facility encourage consumers to buy honey locally, not imported honey. (Photo by Kathy Keatley Garvey)

Susan Cobey
Susan Cobey

BEE BREEDER-GENETICIST Susan Cobey with a frame of her New World Carniolans she rears at the Harry H. Laidlaw Jr. Honey Bee Research Facility, UC Davis. (Photo by Kathy Keatley Garvey)

Posted on Wednesday, March 2, 2011 at 8:04 AM
Tags: antibiotics (2), Eric Mussen (6), Susan Cobey (2), UC Davis (24)

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