- Author: Jeannette E. Warnert
Research by Jim Stapleton, a UC Cooperative Extension advisor and Statewide Integrated Pest Management Program Coordinator for Natural Resources, based at the Kearney Agricultural Research and Extension Center, was published as Feasibility of solar tents for inactivating weedy plant propagative material in the March 2012 issue of the Journal of Pest Science.
Stapleton was inspired to conduct the study when a fire crew came upon a patch of Iberian starthistle growing along a stream in the Sierra foothills near Mariposa. Iberian starthistle is a robust, spiny weed native to the Middle East that, left unchecked, can dominate entire landscapes.
“Crews were going through and cutting dried plants and stacking them, but the seeds survived,” Stapleton said. “If you start moving plant material around with viable seeds, seeds are liable to spread, making the problem worse instead of better.”
Iberian starthistle is only one of many exotic, invasive plants that are capable of transforming California’s open areas into useless and unsightly tracts of land. On rangeland, for example, such weeds diminish desirable annual rangeland feed for cattle and wildlife. Weeds can shade out native wildflowers, make recreational areas inaccessible and, in dense infestations, become a fire laddering fuel.
In the past, such weeds may have been stacked and burned, but fire danger and air quality regulations have forced land managers to find alternatives.
“You wouldn’t want to try this on a 40-acre area,” Stapleton said. “Eradication of weeds with solar tents is best suited for small-scale weed infestations in warm climates.”
For the research project, Stapleton constructed three replicate solar tents with concrete rubble, mulberry shoots and clear plastic tarps. He placed johnsongrass rhizomes inside black trash bags along with about one cup of water. The sample bags were left inside the solar tents for 72 hours.
“Regardless of where you are, regardless of financial resources, you should be able to construct a solar tent,” Stapleton said. “Most of the materials needed – rocks and sticks – are easy to find on site.”
Air temperature inside the sample bags rose to 158 degrees Fahrenheit. Over the three days of the experiment, the rhizomes were exposed to temperatures 140 degrees and higher for 10 hours. None of the rhizome segments treated for three days in the solar tents sprouted. In contrast, rhizomes maintained in clear vegetable storage boxes and kept indoors for comparison all sprouted.
Annotated diagrams for suggested construction of solar tents can be found on the UC Solarization website.
- Author: Jeannette E. Warnert
Freelance photographer Elena Zhukova was at the UC Kearney Agricultural Research and Extension Center March 8 as part of a photo shoot involving all the UC campuses. To browse the professional photos Zhukova shot at other UC locations, visit the UC Office of the President gallery website. Below are snap shots of Zhukova at work at Kearney.
- Author: Jeannette E. Warnert
Felicitas "Lita" Santos is marking her last day at the Kearney Agricultural Research and Extension Center March 8. Santos worked at Kearney for 25 years, much of that time staffing the receptionist's desk in the main academic building. With her cheerful demeanor and vast knowledge of the institution, she has come to be known as "The Face of Kearney."
- Author: Jeannette E. Warnert
Namesake of the UC Kearney Agricultural Research and Extension Center’s postharvest center, F. Gordon Mitchell, died in February. He was 88.
Mr. Mitchell began his distinguished career with the University of California Cooperative Extension immediately following graduation from college in 1949. He was the viticulture advisor in San Joaquin County for eight years before taking a position as statewide pomology specialist at UC Davis in 1957.
During his career, Mr. Mitchell’s work resulted in an industry-wide change to rapid cooling methods, the improvement in fruit packing efficiency, and greater understanding among farmers about the requirements of produce during the postharvest time period. He worked primarily on plums, peaches, nectarines, cherries, pears, strawberries, applies and kiwifruit, however, during his 42-year career conducted research on virtually all pomological commodities.
Mr. Mitchell retired in 1991. When Dinuba farmer/packer LeRoy Giannini contributed funds to build the new postharvest laboratory at Kearney, he suggested naming the building after Mr. Mitchell. On Feb. 8, 1993, the facility was christened the F. Gordon Mitchell Postharvest center.
Emeritus UC Cooperative Extension specialist Jim Thompson of the UC Davis Department of Biological and Agricultural Engineering said Mr. Mitchell worked tirelessly with the California agriculture industry to improve the market for the state’s fresh fruits and tree nuts.
“He developed the early concepts and standards for handling California Granny Smith and Fuji apples, kiwifruit, and pistachio nuts,” Thompson said. “When the tree fruit industry had questions about postharvest issues, their first phone call was to Gordon."
UC Cooperative Extension postharvest horticulturist Mary Lu Arpaia, who is based at the UC Kearney Agricultural Research and Extension Center, counts Mr. Mitchell as a mentor and guidepost for her career.
“Sometimes the best things in life that happen to you are unplanned,” Arpaia said about taking a job in the UC Davis postharvest lab when she was a graduate student. “That job was with Gordon and that was serendipity. When I think back on that one event I know it was one of the most important events in my graduate career and subsequent adventures in life.”
Arpaia said Mr. Mitchell’s work with his colleagues with forced air cooling and packaging established him to be a leader, “albeit a soft spoken one,” in the field of postharvest handling.
Mr. Mitchell was a Davis resident for 55 years. The family obituary described him as a gentle and devoted soul who took great pride in his faith, family and career. Mr. Mitchell is survived by his sister, two sons, a daughter and six grandchildren.
- Author: Jeannette E. Warnert
In recognition of a productive career advancing integrated pest management programs in California and for tireless support of IPM practitioners, UC IPM entomologist Walt Bentley received a Lifetime Achievement Award from the Association of Applied IPM Ecologists.
The award was presented at the association's annual meeting, Feb. 6 in Oxnard, Calif., by his IPM colleague Pete Goodell, a nemotologist who is, like Bentley, based at the UC Kearney Agricultural Research and Extension Center in Parlier, Calif. Goodell is the current president of the Association of Applied IPM Ecologists.
Goodell said a hallmark of Bentley's work has been his ability to connect and empathize with his clientele, an outgrowth of his childhood on a small family farm near Linden, Calif. He began his career with UC Cooperative Extension in 1977 as an entomology farm advisor in Kern County and transferred to his position at Kearney in 1994.
"His projects over the years have addressed real problems of real people," Goodell said. "He spent many hours on farm calls and at the front counter, answering questions, seeking information on the problem and, if required, formulating a plan to seek a solution."
Bentley was part of many research and extension teams formed with campus and county academics to solve local problems, from potato tubermoth to mealy bugs to worm pests in tree fruits and nuts. Bentley focused on the biology of the pest and the weak link in its life cycle where management could employed: chemical, cultural or biological.
Goodell said that Bentley valued outputs and outcomes. He published more than 400 articles in diverse outlets, including the local press, trade magazines, newsletters, ANR publications, UC IPM Pest Management Guidelines, book chapters and peer-reviewed journal articles.