From the College of Agricultural and Environmental Sciences

An interdisciplinary team of scientists and researchers from University of California, Davis, are studying agave plants in the Golden State as farmers are turning to the crop as a potential drought-tolerant option of the future.

The research is centered on studying agave genetics, virus susceptibility, pest control, soil management and crop productivity, said Ron Runnebaum, a viticulture and enology professor who is leading the team of researchers at the newly formed UC Davis Agave Center.  

 “As more and more people are planting, it’s important for us to be engaging with growers to inform the expansion of planting,” Runnebaum said. “We’re fortunate UC Davis has a lot of the expertise from other crops that can be adapted to the emerging industry needs in California.”

The goal of the UC Davis Agave Center is to organize researchers, staff and students around the growing fields of study and education needs of agave growers, processors and distillers.

Agave plants don’t require much water and their hardy leaves are fire resistant. The crop can be used as a fiber, distilled into spirits or converted into a sweetener. That combination of traits could offer an alternative to fallowing fields by switching from thirsty crops to one requiring less water.

UC Davis began investigating the fledgling crop in California after philanthropists and farm owners Stuart and Lisa Woolf established a research fund in their name. The goal: examine if the crop is viable and sustainable in California.

“The only reason that we’ve been able to go out and collect any data is because of the funding Stuart and Lisa provided,” Runnebaum said.

Plant pathologist and postdoctoral researcher Juliana Osse de Souza taking agave samples on a field visit in Huron with Stuart Woolf. (Melissa Haworth / UC Davis)

Agave by the numbers

It’s hard to get an exact count of agave plantings because it’s not a crop tracked by the state. Prior to 2023, less than 50 acres were planted, and in the past year, more than 200 acres were planted, Runnebaum said. This year he will be sending a survey out to farmers in conjunction with UC Agriculture and Natural Resources to get a better sense of the industry.

Two indicators of growth: A symposium held in December at UC Davis attracted more than 160 people and featured a program that included a variety of topics and speakers. The California Agave Council, which co-hosted the event and formed in 2022, is also growing.

At the symposium, California Department of Food and Agriculture Secretary Karen Ross urged growers and others interested in agave as a crop to be mindful of its many uses, economic benefits and environmental impacts.

“Let’s ask all the questions and explore all of the possibilities,” Ross said. “Let’s think about all it can be.”

The value of research

The research need is there, as more plants are brought into California or moved around the state.

Runnebaum and the team have submitted proposals with state, federal and philanthropic funders – the Woolf donation was meant as a seed donation – to be able to expand research and analysis over the long term.

“If we’re not able to get funding for a couple of years there could be a lot of plant material moving around the state that is not characterized as much as it could be,” Runnebaum said.

The team went to agave harvests in Yolo and Santa Barbara counties late last year to collect plant material and take samples to be analyzed back on campus.

“We are able to characterize the plant material by using advanced instrumentation and expertise on campus that individual growers do not readily have access to,” Runnebaum said.

Working with industry is beneficial both ways. It allows UC Davis experts to gain experience in the field and ensures they are addressing the most pressing challenges facing this emerging crop. The data gathered will help growers better quantify the relationship between irrigation and growth, as well as other aspects of the crop.

Interdisciplinary focus

The budding research crosses many areas and could expand with additional investment. Runnebaum is focusing on what temperatures, nutrients, yeast strains and other factors lead to successful fermentation and distilling outcomes of agave grown in California.

The presence of viruses can impact growth and yield and because agave plants are often propagated using vegetative cuttings, the virus can be readily spread to the next field. Plant pathologist Juliana Osse de Souza is looking at known virus diseases in agave plants and the viral load in the collected specimens.   

“Once a plant gets infected by a virus, they are infected for their entire lives,” she said. “This opens a wide range of questions. What is the biological relevance of these viruses?”

Other scientists are looking at plant genomics to develop tools to assist growers. In the field, they are examining what herbicides may provide the best production so growers have access to the effective treatments.

Plant acclimation, growth and productivity under California’s various growing conditions are also being examined.

For more information on how to partner with or contribute to agave research at UC Davis, contact Melissa Haworth at mdhaworth@ucdavis.edu or 530-979-1440.