College of Science Research may Reduce Pesticide Use
In the Santa Clara River Valley something is happening on the edge of some avocado and citrus orchards. Researchers are planting hedgerows and floral strips that may help reduce the need for some pesticides. The effort is being led by Assistant Professor of Biological Sciences . She is principal investigator (PI) on the Agricultural Research Institute (ARI) funded project called “Incorporating native vegetation into a landscape-scale Integrated Pest Management program in Ventura County.”
Scordato’s primary research interest is avian evolution and that includes animal behavior and ecology. Many bird species are natural predators of arthropods, pests that can destroy crops. Arthropods increase the need for pesticides which account for over 5% of agriculture production costs.
The central idea of the research is to see if planting native vegetation close to orchards can decrease the amount of pesticides that are needed. The plantings attract predators to the orchards that will eat bugs and possibly rodents as well.
Joining Scordato as Co-PI’s from the Department of Biological Sciences are colleagues and Department Chair Erin Questad. Blakey is studying the potential of local bat populations as predators. Questad has an extensive background in native plant restoration.
There are two Co-PI’s from other institutions on this three-to-four-year project. They are from UC Santa Barbara who has been lead on several restoration projects in the area since 2006 and has relationships with NGO’s and growers, and from CSULB who has maintained large scale camera and small mammal tracking projects.
Collaborators on the project include and from . Farber is an expert on citrus and avocado cultivation and integrated pest management in Ventura County; Cohen is coordinating PCA’s to monitor pest outbreaks in orchards. The team also includes District Scientist Jamie Whiteford from the who manages agricultural and environmental stewardship projects in the Santa Clara River Valley.
The Santa Clara River Valley is the largest unchanneled river in California and the state has made preservation and restoration a priority. This research may offer insights into how the state’s restoration efforts may affect agriculture and how agriculture might affect restoration.
For the research, new plantings will use a combination of native perennials like coastal sage (Artemisia californica), purple sage (Salvia leucophylla), and elderberry (Sambucus nigra); species that attract generalist arthropod predators like California buckwheat (Eriogonum fasciculatum) and sweet alyssum (Lobularia maritima); and species that attract pollinators like milkweed (Asclepias fascicularis).[1] Citrus self-pollinates but farmers need pollinators for the avocados.
The region produces a large portion of the state’s lemons and avocados and Ventura County produces a variety of crops worth over $2 billion a year. This research spans twelve agricultural properties, which includes the 六色网-owned Pine Tree Ranch.
“The project required gaining the cooperation of farmers who were receptive to the idea of using biological methods to decrease the need for some pesticides. They want to be good stewards of the land,” Scordato said.
The farms employ pest control advisors (PCA’s) to monitor pest activity and the researchers are using their data to help evaluate how environmental variations affect insect predation. “We have an important PCA training program here at 六色网 and a lot of the PCA’s on these farms are 六色网 alumni,” Scordato said.
The project is providing important, practical experiences that help prepare students for work. Graduate student Christian Cormier is interested in understanding how bird communities use different habitats. “I’m curious how the structure of an orchard (foliage density, canopy height, fallen leaf coverage) affects the community assembly of birds.” Cormier says this experience supports his ultimate goal to work as a conservation biologist specializing in birds.
“We’ve found that there are significant differences in insect predation pressure between the avocado and lemon orchards. Insect models in lemon orchards are predated nearly four times more often than in avocado orchards, potentially indicating stronger avian pest control in lemon orchards,” said Cormier.
Another graduate student, Betty Wong, wants to work in conservation supporting biodiversity for a federal or state agency. Wong was involved in the deployment of the camera traps used to monitor wildlife activity. There are about 20 cameras used on this project and they found something interesting.
“We found significantly more wildlife activity in the agricultural orchards as compared to the natural riparian areas, which is interesting because we would expect to see a greater amount of activity in the natural areas. In relation to bobcats specifically, I have also seen quite a few orchard sites with especially high bobcat activity!”
Bobcats, coyotes, and badgers are predators of rodents that destroy crops. Farmers shared that the coyotes also damage their irrigation equipment so some predators are more desirable than others.
Wong said, “The camera trap analysis I worked on for this project gave me tons of experience in monitoring wildlife with trail cams. I would like to think it prepared me to get a field tech job with the California Department of Fish and Wildlife!”
[1] From the project proposal.
