Backyard Orchard News
Two's company. Three's a crowd?
Sometimes we wish it were half a dozen.
Last July we were admiring two newly emerged Gulf Fritillary butterflies on Mexican sunflowers (Tithonia) when a Western Tiger Swallowtail fluttered down, seemingly out of nowhere, to occupy the same sunflower as one Gulf Frit.
The Gulf Fritillary (Agraulis vanillae) and the Western Tiger Swallowtail (Papilio rutulus) eyed each other for a few seconds. Then in the way of the West ("This town isn't big enough for the both of us") the tiger spread its wings and took off.
A Western Tiger Swallowtail readies for a landing on the same flower occupied by a Gulf Fritillary. (Photo by Kathy Keatley Garvey)
Two's company. Three's a crowd? (Photo by Kathy Keatley Garvey)
This year was a 'perfect storm' for California red scale; combine the drought with higher than normal average daily temperatures and pesticides that disrupt scales and you have a crisis.
Drought: Some insect populations increase when trees become water stressed and California red scale is one of those. It could be a direct response to the tree or it could be because increased dust reduces the effectiveness of natural enemies.
Higher than normal temperatures: Typically, San Joaquin Valley conditions produce 4 to 4.5 generations of California red scale per year. Usually, by November 1, the female scales stop producing crawlers and shut down for the winter. This year, the degree days (heat units) were higher than normal the entire red scale season (from March 1 - Dec 1). This produced a full 5th generation of scale and scale crawlers were still emerging in December. Many growers struggled to control California red scale because the problem appeared late in the season and this pest is very difficult to control with insecticides once it reaches the fruit. Degree day units were high not only this year, but have been higher than the 30 year average for the past 3 years, accumulating extra scales each year.
Insecticides: Research has demonstrated that systemic neonicotinoids such as imidacloprid can reduce scale on fruit and leaves but are not effective in controlling California red scale on woody tissues such as bark and twigs. These insecticides are also toxic to natural enemies. Using these products year in and year out builds scale on the wood, that eventually makes its way to fruit.
Below are the flights and five generations of crawler activity at Lindcove Research and Extension Center. Also shown are the degree day units accumulated at Lindcove through the season. See degree day units for California red scale for other locations.
Jeff Mitchell, Cooperative Extension Cropping Systems Specialist at the UC Davis Department of Plant Sciences and Kearney Agricultural Research & Extension Center, recently received a $5000 grant from the agricultural biotechnology company Monsanto to support a program of high school activities aimed at Ag sustainability.
Mitchell will work with the Conservation Agriculture Systems Innovation (CASI) Center, which promotes the principles of conservation agriculture, which include reduced soil disturbance, permanent soil cover cropping, and crop rotation practices.
Jeff Mitchell receiving a $5000 grant from Monsanto.
Jessica, who is majoring in biochemistry and molecular biology, works in the Chiu lab on the Spotted Wing Drosophila (Drosophila suzukii or SWD), a serious pest of fruit crops. In collaboration with scientists in the U.S. and around the world, including Frank Zalom, UC Davis professor of entomology, West is surveying populations of SWD using next-generation sequencing to determine the extent of possible insecticide resistance.
“By correlating her results to insecticide bioassay data, she can start to understand the mechanisms of developing resistance and use this information to help the agricultural industries manage SWD in a more sustainable manner,” said Chiu, an assistant professor.
The UC Global Food Initiative “is a commitment to apply a laser focus on what UC can do as a public research university, in one of the most robust agricultural regions in the world, to take on one of the world's most pressing issues," said UC President Janet Napolitano. This includes research related to food security, health and sustainability.
West received a $2500 stipend. The selection committee said “Jessica's ability to articulate a novel, hypothesis-driven research idea and follow it up with a detailed plan stood out from the rest.”
Said Chiu: “Jessica wrote an outstanding research proposal, detailing how her project can contribute to the mission of the UC Global Food Initiative.”
West applied for--and received--membership in the Class of 2013, Research Scholars Program in Insect Biology (RSPIP), which was organized by three UC Davis Department of Entomology faculty (Jay Rosenheim, Louie Yang and Joanna Chiu) to provide undergraduates with closely mentored research experiences in biology. The program's goal is "to provide academically strong and highly motivated undergraduates with a multi-year research experience that cultivates skills that will prepare them for a career in biological research and useful for students whose career goals will take them to medical school, veterinary school, or graduate programs in any biological sub-discipline."
Undergraduates can easily feel like they are lost in the crowd, Chui said, and rarely get close mentorship from faculty or other research staff. The RSIBP program fills that bill. “It is highly competitive and being selected is not an easy feat in itself,” Chiu said. West was one of eight students from the pool of 50 applicants selected.
Insects can be used as model systems to explore virtually any area of biology (population biology; behavior and ecology; biodiversity and evolutionary ecology; agroecology; genetics and molecular biology; biochemistry and physiology; and cell biology).
The Chiu lab collaborates with the Zalom lab and with research groups at Oregon State University, Washington State University, North Carolina State University, University of Georgia, and Cornell University to develop pest management strategies to combat SWD. Most drosophila flies feed on spoiled fruits, but SWD prefers fresh fruit (berries and soft-skinned fruits). The national crop loss has been estimated at more than $700 million annually.
“As a result, to control pest population and reduce crop loss, growers now rely on preventive applications of broad-spectrum neuroactive insecticides,” Chiu explained. “The selection pressure for insecticide resistance is therefore extremely high and will likely lead to resistance development in SWD, which threatens the sustainability of these high value crops.”
“Our laboratory has already set up a large network of collaborators all over the world to support this project,” Chiu said. “Jessica regards this project as an opportunity to explore new research areas, while contributing to an urgent food crisis as the crop industries and growers all over the world are becoming gravely concerned. “
Jessica West and her mentor, Joanna Chui, are a good fit. And that should mean bad news for the spotted wing drosophila.
UC Davis undergraduate student Jessica West, who is majoring in biochemistry and molecular biology, has just received the UC Davis undergraduate award President's Global Food Initiative Student Fellowship Program. (Photo by Kathy Keatley Garvey)
What's that wet stuff falling from California skies?
Could it be the "R" word, rain?
Or what Wikipedia calls "liquid water in the form of droplets that have condensed from atmospheric water vapor and then precipitated—that is, become heavy enough to fall under gravity?"
A winter storm is pummelling California, soaking the parched earth. Talk about drenching the three-year historic drought. We're getting reacquainted with umbrellas, raincoats and rain boots. And leaky roofs, heavy sandbags, massive flooding, and power outages.
Of course, the drought is far from over.
Reporter Paul Rogers, in a piece in today's San Jose Mercury News headlined “California Drought: Winter Storms Finally Starting to Boost Storage Levels in Key Reservoirs," quoted Jay Lund, director of the UC Davis Center for Watershed Sciences as saying: ""It's the middle of December, and we've had two good storm systems. This could be the end of the drought; we won't know until late March. But it is certainly an easing of the drought."
On the UC Davis campus, everyone received an Aggie Alert on Wednesday morning, Dec. 10: "A severe winter storm with high winds and heavy rain is forecast for northern California beginning about 10 p.m. this evening, Wednesday, Dec. 10 and continuing through Thursday. At this time, there are no plans to cancel classes or suspend campus operations, but plan for travel delays and use caution when moving around campus. For once, cycling is not recommended."
When cycling is not recommended on the UC Davis campus, that means this is serious rain.
Let's hope we get more of this serious rain. It's been a long time since we've seen rain drops on ladybugs.
Rain drops falling on a lady beetle, aka ladybug. (Photo by Kathy Keatley Garvey)