UC Blog
European grapevine moth found in Merced Co.
Three European grapevine moths found recently in a northeast Merced County vineyard mean six grape-growing California counties are now dealing with the new pest, according to an article over the weekend in the Fresno Bee.
The pest, a native of southern Italy, made its first California appearance last fall in Napa County. It has also been trapped in Solano, Sonoma, Mendocino and Fresno counties.
Writer Robert Rodriguez reported that the Merced agricultural commissioner was surprised by the local find. Only about 12,000 acres of vineyards are within the county borders; by contrast, Fresno County as 190,000 acres.
Fresno County UCCE viticulture farm advisor Stephen Vasquez told Rodriguez that he has received dozens of calls from growers about the European grapevine moth since the ag commissioner announced the pest was trapped in three Fresno County locations in late April and early May.
"Farmers want to know how to kill it and what will they have to do as part of the quarantine," Vasquez was quoted in the story. "Many are concerned about their ability to move fruit in and out of the area."
UC Cooperative Extension is working with the ag commissioner's office to offer four grower meetings about the pest in Fresno County. They will be held:
- 10 a.m. to 12 noon Wednesday, May 19, at the UC Kearney Research and Extension Center near Parlier.
- 1 to 3 p.m. Wednesday, May 19, at UC KREC
- 10 a.m to 12 noon Saturday, May 22, at the California Tree Fruit Agreement office in Reedley.
- 6 to 8 p.m. Thursday, May 27, at the Fresno County Farm Bureau office in Fresno.
At each of the meetings, growers will learn about European grapevine moth life cycle, the monitoring program, quarantine guidelines and more. For details, see the meeting flyer. More information about the pest is available on the UC Integrated Pest Management website.
European grapevine moth.
UC nitrate *quick test* protects water quality
Lettuce farmers can use less fertilizer - saving money, cutting back water use and reducing nitrate groundwater contamination risk - without sacrificing crop yield by employing a "quick test" developed by UC Cooperative Extension, the San Francisco Chronicle reported today.
With the quick test, growers can determine how much nitrogen is in the soil and use only as much fertilizer as their lettuce needs to grow.
UC Cooperative Extension farm advisor Michael Cahn told reporter Julia Scott that he helped one company use 70 pounds less fertilizer per acre and get the same yield.
The Chronicle story was focused on imposing regulations to ease water nitrate contamination in California. Cal State East Bay earth and environmental science professor Jean Moran pointed to agriculture as the primary source of the problem.
"It covers a much larger area, it's a constant input of nitrates in groundwater and you have constant irrigation and over-irrigation, which drives the nitrates deeper into the groundwater," Moran was quoted. "But if you look for new evidence of regulations on nitrate issues in groundwater, you just don't find them."
Lettuce irrigation.
USDA and UC join forces against potato psyllid
Scientists at USDA's Agricultural Research Service and UC Riverside will work together to develop a chemical attractant to monitor and manage the potato psyllid, according to an ARS news release issued today.
The psyllid harms the potato industry in two ways. Toxins emitted when the pest feeds causes psyllid yellows and an organism vectored by the psyllids causes a condition known as "zebra chip."
Zebra chip happens when sugars accumulate in some areas of the tuber instead of starch. Dark lines run the length of affected potatoes. In chipping varieties, these areas turn black when the chips are fried, creating a black, striped effect that gives rise to the name "zebra chip," according to the UC IPM Pest Note on potato psyllid.
Under a six-month cooperative agreement, UC Riverside entomologist Jocelyn Millar and ARS scientists in Wapato, Wash., will together try to isolate, identify, synthesize and test the specific chemical or chemicals that female potato psyllids use to attract mates.
"The agreement between UC Riverside and ARS is a pooling of resources and personnel that leverages Millar’s research on insect chemical ecology with the Wapato team’s behavioral assay studies," said the news release, written by Jan Suszkiw.
ARS scientists look at "zebra chips."
UC expert speaks at Lodi town hall meeting
A town hall meeting yesterday, hosted by the North San Joaquin Water Conservation District, included comments from UC Davis Cooperative Extension groundwater hydrology specialist Thomas Harter, according to an account in the Lodi-News Sentinel.
The discussion centered on a local ballot initiative to fund the development of infrastructure for groundwater recharge. The story said authorities are working to solve "the region's groundwater crisis."
"The ground isn't sinking like in Bakersfield," said the general manager of the Stockton East Water District. "But if we don't act on it, that's what we are looking at."
Harter provided general information about groundwater hydrology at the meeting, the newspaper reported.
"Groundwater is like a bank account, if you take more out than you put in, you will have a lower balance," Harter was quoted. "It will be a matter of decades, not weeks or months, to refill the basin."
The upcoming ballot initiative, Measure C, would enable the district to collect a fee for pumping groundwater, the story said.
For groundwater links, publications, research and a blog, see Harter's Groundwater Hydrology website.
Thomas Harter.
Researchers respond to Sac Bee Sierra grazing story
UC Davis Cooperative Extension researchers Ken Tate and Rob Atwill responded to a story about High Sierra grazing published last month in the Sacramento Bee in the California Farm Bureau Federation's newspaper AgAlert.
The Sacramento Bee story suggested that cattle grazing in high-elevation areas of the Sierra Nevada causes water contamination. Following is an opening excerpt of Atwill and Tate's commentary. See the AgAlert link for the complete 600-word response:
"Our shared challenge is to continue to identify and enact grazing practices which reduce pollution risks, enhance watershed health and sustain agricultural enterprises.
"All of our local communities are reeling from budget blows and decreasing revenues. Our local rural communities depend on livestock grazing and associated businesses for a stable economy.
"Sustainable food production and natural resources are crucial to our state, country and world. We all depend upon healthy watersheds."
Ken Tate, left, and Rob Atwill.