Michoacan is burning. A drug cartel that takes its name from an ancient monastic order has set fire to lumber yards, packing plants and passenger buses in a medieval-like reign of terror.

The Knights Templar cartel is extorting protection payments from cattlemen, lime growers and businesses such as butchers, prompting a backlash in the western agricultural state, where some communities are fighting back, taking up arms in vigilante patrols.

Lime picker Alejandro Ayala chose to seek help from the law instead. After the cartel forced him out of work by shutting down fruit warehouses, he and several dozen co-workers, escorted by Federal Police, met on April 10 with then-state Interior Secretary Jesus Reyna, now the acting governor.

The 41-year-old father of two only wanted to get back to work, said his wife, Martha Elena Murguia Morales.

But, as often happens, the cartel responded before the government did.

On the way back, Ayala’s convoy was ambushed, twice. He and nine others were killed.

“I called him after the first one, and he said, ‘They shot at us, but I’m OK,’” Murguia Morales said. “Then I called him again, and he didn’t answer.”

Help finally arrived Sunday when thousands of soldiers rolled in to restore order. The government of President Enrique Pena Nieto says troops will stay in Michoacan until every citizen lives in peace. But the offensive, headed by Secretary of Defense Salvador Cienfuegos, looks a lot like failed operations launched previously by former President Felipe Calderon, who started his first assault on organized crime in Michoacan shortly after taking office in late 2006.

Calderon was trying to stop drug cartels from morphing into mafias controlling all segments of society. But that’s exactly what has happened, as they maintain country roads, control the local economy and mete out justice for common crimes.

In the Tierra Caliente, a remote agricultural region, fire has been a favorite weapon of the cartel. On the highway between Coalcoman and La Ruana, the ruins of three sawmills torched by the cartel still smoldered this week.

The owners reportedly had failed to pay protection fees of 120 pesos (about $10) for every cubic meter of wood they sold, the equivalent of about 10 cents for every two-by-four board.

The Knights Templar also demands that avocado growers pay 2,000 pesos (about $160) per hectare of trees. Avocado warehouses were set afire this month by armed men.

The heart of a conflict where a mafia openly rules and the government is largely absent is nowhere more evident than in the lime groves that cover the hot, hilly plains, miles and miles of trees with the fruit yellowing and falling into uncollected heaps on the ground.

Mexico is the world’s largest producer of limes, according to the U.S. Department of Agriculture, more than 2 million tons in 2012. Much of its exports go to the United States, and Michoacan contributes a large share of that: nearly 475,000 tons of the fruit last year, half from the Tierra Caliente.

It sometimes seems like everything in Mexico, from tacos to potato chips to beer, gets a squeeze of lime.

By late last year, the cartel wasn’t just extorting money from lime growers and packers. It had started charging per-box payments from lime pickers, who make only $10 to $15 per day laboring under the scorching sun.

With officials doing nothing to help, self-defense groups started to spring up in February to fight back. Heavily armed men in masks and baseball caps began manning barricades along highways and patrolling the countryside, sometimes openly battling the cartel.