Division of Agriculture and Natural Resources
Division of Agriculture and Natural Resources
Division of Agriculture and Natural Resources
University of California
Division of Agriculture and Natural Resources

UC blogs

What’s the difference between yams and sweetpotatoes?

Do you know the difference between a yam and a sweetpotato?

“A true yam is not grown in the U.S., it's found in South America,” says Jason Tucker, vice president of the California Sweetpotato Council. Real yams have dry, dark flesh and are not the same plant species as sweetpotatoes, he explained.

“A yam is a sweetpotato, at least for those grown in the U.S.”, says Scott Stoddard, UC Cooperative Extension advisor in Merced County. “The rest of country has predominately just one type of sweetpotato, with tan skin and orange flesh, but in California, we have four marketing classes.”

The four kinds of California sweetpotatoes are

  • Jewell, with tan skin and orange flesh
  • Jersey, with light yellow skin and white flesh
  • Oriental, with purple skin and white flesh
  • Garnet, with red skin and deep orange flesh

The red-skinned sweetpotatoes are what many people in the United States call yams.

The California Sweetpotato Council spells sweetpotato as one word because it isn't a potato, it is a different plant species.

Sweetpotato classes, from left, are Jewell, Oriental, Jersey and Garnet. Photo courtesy of the California Sweetpotato Council.
Posted on Friday, November 21, 2014 at 8:26 AM

The food vs. fuel debate: Growing biofuel in the U.S.

Studies suggest biofuel can be grown on 'marginal land,' but no standard definition of 'marginal land' exists.
In order to slow global climate change and achieve greater energy independence, Americans are showing an increasing interest in switching over to clean, renewable fuels made from home-grown crops. In fact, Congress has mandated that at least 16 billion gallons of cellulosic ethanol be added to the U.S. fuel supply by 2022.

However, estimates suggest that growing crops to produce that much biofuel would require 40 to 50 million acres of land, an area roughly equivalent in size to the entire state of Nebraska.

“If we convert cropland that now produces food into fuel production, what will that do to our food supply?” asks Maggi Kelly, UC Cooperative Extension specialist and the director of the UC Division of Agriculture and Natural Resources Statewide IGIS Program. “If we begin growing fuel crops on land that isn't currently in agriculture, will that come at the expense of wildlife habitat and open space, clean water and scenic views?”

Kelly and UC Berkeley graduate student Sarah Lewis are conducting research to better understand land-use options for growing biofuel feed stock. They used a literature search, in which the results of multiple projects conducted around the world are reviewed, aggregated and compared. 

“When food vs. fuel land questions are raised in the literature, authors often suggest fuel crops be planted on ‘marginal land,'” Kelly said. “But what does that actually mean? Delving into the literature, we found there was no standard definition of ‘marginal land.'”

Kelly and Lewis' literature review focused on projects that used geospatial technology to explicitly map marginal, abandoned or degraded lands specifically for the purpose of planting bioenergy crops. They narrowed their search to 21 papers from 2008 to 2013, and among them they found no common working definition of marginal land.

“We have to be careful when we talk about what is marginal. We have to be explicit about our definitions, mapping and modeling,” Kelly said. “In our lab, we are trying to understand the landscape under multiple lenses and prioritize different uses and determine how management regimes impact the land.”

The research report, titled Mapping the Potential for Biofuel Production on Marginal Lands: Differences in Definitions, Data and Models across Scales, was published in the International Journal for Geo-Information.

Click here for this story in Spanish.

An initiative to improve energy security and green technologies is part of the UC Division of Agriculture and Naturalist Resources Strategic Vision 2025.

 

Posted on Friday, November 21, 2014 at 7:45 AM

Parents can make healthful eating fun for kids

Guide for parents helps teach kids healthy practices early in life.
New parents sometimes joke that they wish babies, like consumer products, would come with an instruction manual. Because, ultimately, parents want to do what's best to keep their children healthy, but what's best to do isn't always intuitive. To help to make it easier for parents, UC Division of Agriculture and Natural Resources offers a short guide, called “Healthy, Happy Families” to help parents teach their kids about nutrition.

Studies have shown that we develop our eating habits early in life, according to lead author Lenna Ontai, UC Cooperative Extension specialist in the Department of Human and Community Development at UC Davis.

“We know that it is not enough to just teach parents what to do. We have to support them in how they can take that knowledge home and use it effectively,” said Ontai.

Healthy, Happy Families provides parents with practical information about how children develop and tips for raising a healthy and happy child. It includes fun and easy activities for parents to do with their preschool-aged children to promote healthful eating.

Children who spend more time with their parents tend to be happier and learn better, the authors write. They recommend eating together as a family to help children learn to make healthy food choices. Letting children help plan and prepare meals helps them develop new skills. Children also learn social skills during family meals such as talking and listening.

Now available in Spanish!
Each of the eight lessons is designed to take 15-20 minutes. The book includes suggestions for encouraging positive behavior and activities such as cooking together. To entice children to try new, nutritious foods, let them explore textures, tastes, colors and sounds of food. Fuzzy kiwifruit, sour apples, red peppers and crunchy celery may pique their interest.

For cooking with kids, they recommend

  • Explaining why it's important to wash our hands.
  • Setting up an area for the child that is away from the stove and oven.
  • Using a low table or safe step stool.
  • Letting the child taste.
  • Using child-sized utensils.
  • And most of all, making it fun!

In a fun way, parents can create a healthy learning environment and teach their children healthful habits that will last a lifetime.

“Helping parents tune into their children's development and supporting positive interactions around food makes a big difference as children grow,” Ontai said. 

The Healthy, Happy Families workbook is available in packages of 10 for $15 in English and is now available in Spanish as Familia sana, familia feliz in Spanish. There is also a companion publication for teachers called the Healthy, Happy Families for Teachers curriculum. All three publications can be ordered at http://anrcatalog.ucdavis.edu.

Posted on Thursday, November 20, 2014 at 8:04 AM

UC scientists help clarify use of insecticide

Argentine ants tending brown soft scale on a citrus twig. Chlorpyrifos is sometimes necessary to control ants in citrus.
The insecticide chlorpyrifos is a critically important tool for California producers of alfalfa, almonds, citrus and cotton, according to a comprehensive report coordinated by the UC Statewide Integrated Pest Management Program. As part of an action plan, the report identifies specific research, extension and policy gaps that should be addressed to ensure safe, effective use of the insecticide.

The report, Identifying and Managing Critical Uses of Chlorpyrifos in Alfalfa, Almonds, Citrus and Cotton, was commissioned by the California Department of Pesticide Regulation (CDPR) earlier this year and submitted by UC IPM in October 2014.

“We feel the department entrusted UC IPM with this task because of its reputation for developing effective IPM systems and its track record in bringing groups together to address challenging issues,” said Pete Goodell, UC Cooperative Extension advisor for integrated pest management and report principal investigator. Lori Berger, also of the statewide IPM program, was the project coordinator.

To gather input for the report, Goodell and Berger formed four “crop teams” with leaders from the alfalfa, almond, citrus and cotton industries. While chlorpyrifos is used in many of California's more than 300 crops, these four crops were selected due to the amount of acreage treated and insecticide use patterns. Combined, these commodities are grown on about 2.5 million acres and valued at more than $10 billion per year in California.

Chlorpyrifos is a common insecticide used under the trade names Lorsban, Lock-on and generic formulations to control ants, stink bugs, aphids, whiteflies and other pests. The report details the insecticide's use patterns as compared to other pest control tactics, such as resistant varieties, mating disruption, field sanitation and other insecticides.

“Our industry teams told us that chlorpyrifos is an essential component of their IPM programs,” Goodell said. “The teams believe decision support tools would be useful to help pest control advisers and growers recognize the critical use scenarios that require its application.”

As a part of the discussions, the teams asked that CDPR develop comprehensive, science-based information about the specific risk pathways posed by chlorpyrifos and work with the industry to develop any new application safety measures. The representatives of the agricultural community also asked that new human health data from the U.S. Environmental Protection Agency be considered in future CDPR regulatory decision-making to ensure that the most current data available informs their decisions.

For the second phase of the project, UC IPM will hold outreach meetings in 2015 and 2016 for pest control advisers, UCCE farm advisors, commodity group representatives and farmers who grow alfalfa, almonds, citrus and cotton.

“There is a new generation of professionals coming into the field,” Goodell said. “UC's IPM Program is well-prepared to equip them with decision-making tools that include a wide variety of insect management options.”

The full report can be found on the CDPR website: http://cdpr.ca.gov/docs/pestmgt/crit_uses.htm

An initiative to manage endemic and invasive pests and diseases is part of the UC Division of Agriculture and Natural Resources Strategic Vision 2025.

Posted on Monday, November 17, 2014 at 11:07 AM

Students' olive-oil fraud buster wins international prize

The iGEM olive-oil biosensor inventors are, from left, James Lucas, Sarah Ritz, Simon Staley, Yeonju Song, Brian Tamsut and Lucas Murray. Not pictured here was team member Aaron Cohen. (Karen Higgins/UC Davis)
A student team composed of some of the best and brightest young minds at UC Davis took the grand prize last week in an international competition for the high-tech biosensor they created to detect low-grade or adulterated olive oil.

The award was presented to the Aggie inventors during the finals of the three-day global iGEM (International Genetically Engineered Machines) competition in Boston. The competition, this year featuring 245 teams from Asia, Europe, Latin America and North America, challenges student teams to design and build biological systems or machines and present their inventions in the international competition.

The students had spent several months designing and building the palm-sized biosensor, which they dubbed OliView. The biosensor is equipped to quickly and easily evaluate the chemical profile of oil, providing producers, distributors, retailers and ultimately consumers with an effective, inexpensive way to ensure olive oil quality.

Verifying olive oil quality is a concern for consumers – many of whom are willing to pay higher prices for the health benefits and flavor of true, extra-virgin olive oil. And honest olive oil producers want to prevent other producers from passing off sub-par olive oil as the real deal, while retailers, distributors and producers want a quick, easy way to ensure olive oil quality.

In addition helping detect fraudulent olive oil, the students' new biosensor will also monitor for good oil that may have gone rancid with age. 

The team of undergraduate students included Lucas Murray, Brian Tamsut, James Lucas, Sarah Ritz, Aaron Cohen and Simon Staley, with Yeonju Song serving as the “shadow” or alternate team member. You can tune into Aaron Cohen's recent Nov. 6 Science Friday interview during a discussion of synthetic biology.

The full story and a brief video about the new olive-oil biosensor and this stellar team of young inventors are available at: http://news.ucdavis.edu/search/news_detail.lasso?id=11076.

Reports on olive-oil quality are available at the web site of the UC Davis Olive Center at: http://olivecenter.ucdavis.edu/research/reports.

Posted on Wednesday, November 12, 2014 at 1:17 PM

Next 5 stories | Last story

Webmaster Email: jewarnert@ucanr.edu