Tala, Mexico ? Men with machetes still hack at tequila-producing agave plants; corn stalks still sway in fields dotted with ancient stone churches. But one element is missing from the timeless, picturesque scene: There is not a burro in sight.

“There used to be 50 in every town. Now there is one, if that,” said Nicolas Vazquez Ortega, a ranch manager. “Before you used to see packs of mules and donkeys in the fields when you were driving along the road. Now they are disappearing.”

Although it seems as improbable as Hawaii running out of pineapples or France without Beaujolais, Mexico has a shortage of donkeys. As farmers abandon the countryside for big cities, move to the United States or shift to tractors and cargo trucks, burros — long a backbone of Mexican agriculture and a symbol of Mexican life — have become increasingly scarce.

This trend has so alarmed officials in Jalisco, one of Mexico’s most important agricultural states, that they are planning to import donkeys from Kentucky to revive the dwindling population. The project, they said, will bring economic benefits to ailing rural areas, where many poor farmers still depend on beasts of burden.

Many farmers have shunned donkeys because of their negative association with poverty and backwardness, officials said. Now, as the animals have started disappearing, people are “realizing their importance,” said Martin Martinez Cervantes, a Jalisco rural development official.

Farmers say they cause less damage than machines amid the tight rows of blue agave, the spike-leaved plants that produce tequila. Coffee growers in other states say they get better traction than trucks on highland slopes. And in many remote areas with no roads, they are still the only ride home.

Martinez said the demand for donkeys began to dwindle as more young, rural Mexicans relocated in the United States and began sending home enough money for their parents to buy a tractor or a pickup.

Some farmers who shunned donkeys for the efficiency and status of modern machines now regret their haste.

Felipe de Jesus Padilla Robles, 81, a farmer in Tala, said he always took good care of his donkey, whom he has now outlived. For years, he said, the two of them worked alongside each other in the sugar cane and corn fields. “We understood each other,” he said.