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After phasing out methyl bromide, growers grapple with crop disease while encountering regulations, labor shortages

Tim Hearden, Western Farm Press

March 20, 2020

7 Min Read
Peter Navarro
Second-generation farmer Peter Navarro stands in his strawberry field in Watsonville, Calif. He says it’s getting more difficult to grow the berries in California as regulations and labor shortages persist.Tim Hearden

[Note: This is the second in a series of articles examining what California agriculture could look like by 2030 – a decade from now.]

Second-generation farmer Peter Navarro has seen the industry go through significant changes since his father and uncle arrived in the Pajaro Valley on California’s Central Coast as laborers in the 1950s.

As he and other growers have phased out their use of methyl bromide as a fumigant, he’s switched to newly developed varieties that are more resistant to soilborne diseases – and he produces more berries on fewer acres.

“Right now we’re down to 50 acres,” said Navarro, a California Strawberry Commission board member. “In the Pajaro Valley, the average you see is smaller plots. In the Salinas Valley, the plots are larger.”

OBSTACLES REMAIN

But no shortage of challenges remain for a strawberry industry that produced California’s sixth most valuable crop in 2018 at $2.34 billion in cash farm receipts, according to the state Department of Food and Agriculture. As with other commodities, labor shortage and regulations are making it more expensive to grow a crop, and then there’s the weather.

For instance, the unseasonable rainstorm that hit much of California late last spring came just as berries were sizing up for the peak season, said Navarro, who also grows raspberries and blackberries. The rain interfered with pollination, causing what’s known as crooked fruit, and then was followed by an early-June heat wave.

Related:California ag faces a decade of challenges

“It’s a difficult process,” Navarro said of growing berries. “Strawberry plants are delicate. Any disease can take them down.”

And the industry will face an even more uphill battle when the chloropicrin and Telone that have replaced methyl bromide as go-to fumigants become too expensive or are regulated out of existence, University of California, Santa Cruz sociologist Judy Guthman asserts in a new book.

“California produces the best berries in the world, but it’s getting harder and harder to grow here,” Navarro told Western Farm Press. “Everything we do and use – the ground preparation, the plants, the plastic – all have restrictions and laws. And labor is probably our No. 1 issue, with wages going up every year, health insurance and the sick pay issue.”

SUCCESS STORY

Navarro’s remarks come as virtually every commodity in California is grappling with the winds of regulatory and market change. Yet while other leading industries such as almonds and wine grab much of the fanfare for their sustainability push, one would be hard-pressed to find a more resilient lot than the state’s strawberry growers in the past decade.

As Guthman notes in her book Wilted: Pathogens, Chemicals and the Fragile Future of the California Strawberry Industry, strawberries were introduced in California during the 1880s and have benefitted from decades of UC and private breeding efforts that led to improvements in productivity and taste.

Despite taking frequent criticism for their backbreaking labor conditions and reliance on highly toxic chemical fumigants, strawberries became the nation’s favorite berry, leading the category in volume and value, according to the strawberry commission.

Strawberries are now a year-round fruit in California, with harvests moving south with the winter sun, and the state accounts for 88 percent of U.S. production. The industry has been on a production winning streak in recent years, setting records in seven out of eight years from 2006-2013 and establishing new records – by far – in 2017 and 2018.

But as Guthman observes, much of the industry’s success over the years can be traced to methyl bromide, which was growers’ predominant tool for controlling the soilborne pathogens to which the industry is particularly vulnerable.

METHYL BROMIDE

Under a global treaty negotiated in the 1990s, most methyl bromide use was eliminated by 2005, but strawberry growers relied on critical use exemptions until the chemical was phased out of that industry in 2016. The two remaining available fumigants, chloropicrin and Telone, are facing increased scrutiny by state regulators and will likely eventually be phased out, too, researchers warn.

Their elimination could jeopardize the future of the industry, Guthman argues.

“The California strawberry industry, so dependent on fumigants, has been bred for the wrong things and subsequently is not now poised to be particularly resilient to the change foisted upon it by their loss,” UC Cooperative Extension strawberry advisor Mark Bolda wrote in a blog post in November.

“Breeding has been built around methyl bromide, land use is determined around the ability to fumigate out problems and return to it with little time for rotation and rest, and labor is dependent upon the high yields enabled by fumigation,” Bolda wrote. “It all fits together under efficacious fumigation, and will all fall apart without it.”

Overall organic acreage in California rose from 3,420 acres in 2015 to a projected 4,204 acres in 2020, but UC scientists point out that organic growers still encounter such problems as nutrient deficiency, for which they are unable to use the controlled-release fertilizers that conventional growers use.

“It’s just so expensive to grow a crop,” said Navarro, the Watsonville, Calif., grower. “I personally have not grown organic. There could be more challenges, such as more susceptibility to diseases and invasive pests. If you continue to grow on the same ground, it’s even more of a challenge. You do have to invest a lot into soil to keep it productive.”

PUSH FOR RESEARCH

Just as San Joaquin Valley fruit and nut tree growers are scrambling to improve water efficiencies before the next drought, the California Strawberry Commission and other entities have placed a heavy emphasis on research.

Among alternative concepts that scientists from the UC and elsewhere have been working on in recent years are raised bed troughs, “soilless” fields and anaerobic soil disinfestation. In 2017, a team of scientists based at UC Santa Cruz received a $2.5 million USDA grant to further research biological soil disinfestation, crop rotation and other natural methods for fumigating soil, according to the strawberry commission.

Steve Fennemore, a UC plant sciences specialist in Salinas, has spent more than 20 years seeking alternatives to methyl bromide. Among his efforts has been to steam-clean soil using a tractor outfitted with a boiler; he went to Norway in September to meet with a company with a commercial steamer.

While achieving buy-in among industry leaders has been a challenge, Fennemore says steam fumigation has worked better in field trials than anaerobic soil disinfestation – using flooding to change the soil’s microbial ecology. He envisions growers hiring the companies to steam-fumigate their fields, or at least the most critical acres, he said.

“It’s not cheap,” Fennemore told Western Farm Press. “We’ll have to find a way to do it less expensively.”

NEW VARIETIES

With production getting more expensive, growers are gravitating to more prolific varieties developed by the UCCE, other agencies and private companies. Among the more popular new varieties are the UC-developed Monterey and San Andreas strawberries, both of which are “day-neutral” varieties that are more tolerant of summer heat and more resistant to diseases.

Meanwhile, the strawberry commission recently committed up to $5 million over five years to establish and grow a strawberry research center at California Polytechnic University, San Luis Obispo. The center has grown to 10 acres of farmland and has a team specializing in plant pathology, entomology and automation.

In the past several years, the commission and the center have sponsored a daylong growers’ workshop to showcase advances in production automation, highlighting on-farm robotics and integration of digital technologies in strawberry production, according to a news release.

The UCCE’s Bolda believes the answer to overcoming the industry’s obstacles lies “in a number of practices, not all of them necessarily directed at reducing or resisting soil pathogens, being used together,” he wrote.

WORKING TOGETHER

“Developing something this complex takes the input of people from multiple disciplines,” he added, “and we in the research community, from breeders, to plant pathologists, to pomologists, to growers, both from the public and private sector, have been doing just that for at least the past several years. We don’t have the solution yet, but we will get there, I am certain.”

Both Navarro and Fennemore expect acreage to continue to decline in the next decade. But plantings in 2020 are expected to increase slightly to a little more than 32,000 acres, and volume “is expected to reach record levels from Easter to Independence Day,” the commission declared in its annual acreage report in December.

Navarro tries to remain optimistic.

“Every day is a different challenge,” he said. “It’s good because we were raised this way. You’re outside. It’s something we like to do. I think overall we’re doing a really good job.”

[Next month: Is there money to be made from meeting more stringent production standards, and what industries could benefit the most?

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