Jeremy Bagott is the author of “Guaconomics.”

When President Trump began blustering in late March about shutting the border with Mexico, possibly blocking produce-laden trucks and other cross-border commerce, long-suffering U.S. avocado growers could have been excused if they had erupted in a fit of pre-Cinco de Mayo merriment and broken out some strictly U.S.-sourced guacamole.

Avocado growers in California, who once produced 90 percent of the avocados consumed in the United States, remember 1997 as the year of the original sin, when the U.S. Agriculture Department substantially lifted an 83-year-old ban on the importation of Mexican avocados. The ban had been enacted in 1914 to safeguard U.S. avocado production from pests such as the seed weevil. As protectionist measures fell after passage of the North American Free Trade Agreement in 1993, the acceptance of avocados grown in Mexico in turn safeguarded U.S. exports of corn, pork and dairy products to Mexico.

The flow of creamy green gold from Mexico clearly whetted American appetites. In 1989, annual per capita avocado consumption in the United States had been just 1.1 pounds. By 2017-2018, the average American was downing 7.47 pounds of avocados a year.

Avocados once were mostly reserved for special events such as hotel brunches — those remarkable repasts of the 1970s and ’80s in which bite-size bay shrimp were mixed with mayonnaise and scallions and carefully placed into the natural depression of a chilled, ripe avocado. Today, we expect to find the fruit with heart-healthy fats (yes, Persea americana is a fruit) even in our Subway sandwiches and gas-station sushi rolls.

The shift may have roused the U.S. palate, but growers north of the border, almost entirely in California, haven’t fared so well. The years after 1997 saw orchards being sold off piecemeal as “vanity ranches.” Nearly all of California’s central and southern coastal counties, those of San Diego, Ventura, Santa Barbara, San Luis Obispo and Monterey, were affected. Some orchards were sold largely for the value of their farmhouses; developers coveted the land for residential subdivisions. Groves were also marketed to well-heeled buyers to generate paper losses or offset property taxes. Many properties lost their grandfathered rights to cheap water as orchards were demolished. 

With lower labor and land costs than their U.S. counterparts, Mexican avocado growers increased production after 1997, and why wouldn’t they? The United States is now the top export market for Mexico, consuming about 75 percent of total Mexican avocado exports. Mexican distributors now have the luxury of holding out for better price — avocado surge pricing — during periods of increased demand. The rawest neophyte in the orchards of Michoacán is now keenly aware of Super Bowl, March Madness and Cinco de Mayo. Ironically, Cinco de Mayo isn’t widely observed in Mexico except in the states of Veracruz and Puebla, where the Battle of Puebla, a victory over the French, occurred on that date in 1862.

The avocado commerce is almost entirely a one-way street: “In 2017, the United States imported $2.6 billion in fresh avocados,” said the Agricultural Marketing Resource Center, citing government figures, “and exported approximately $28,500 in fresh avocados.”

The U.S. mania for avocados shows no signs of abating; witness the current obsession with avocado toast, a phenomenon that some attribute to actress and lifestyle-monger Gwyneth Paltrow, who featured the crunchy-yet-mushy combo in her 2013 cookbook, “It’s All Good.” Two years later, singer Miley Cyrus got a tattoo of an avocado half (no seed) on her left arm. “Dear Avocado,” she wrote on Instagram, “I love you so much.”

In 2014, Americans ordered $17,000 in avocado toast at restaurants per month; by 2017, the monthly amount had increased to $900,000.

As in so many economic realms these days, China’s rise must be taken into account. A decade ago, avocado imports to China were negligible. The Chinese have since developed a taste for avocados, and imports from Latin American countries increased to 76 million pounds in the 2016-2017 season. It will be years, though, before Chinese demand would present a rivalry for U.S. consumers, who consumed more than 2 billion pounds of avocados last year. Of more concern to U.S. diners hungering for guacamole or avocado toast: Reuters reported that if Trump ever makes good on his threat to close the border with Mexico, the United States’ avocado supply would run out in three weeks.

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