Thousands of ancient olive trees laden with fruits, just ahead of what promised to be a bumper crop for Italy’s olive producers, have been marked with a blood-red X. They are supposed to be cut down by government officials, immediately, in hopes of stopping the spread of a deadly plant bacterium that is spreading across southern Italy’s olive trees and could threaten all those across Europe.* But grassroots activists who are helping the farmers resist the slaughter are gaining ground by enlisting lawyers to fight for farmers’ rights. They are also calling for civil disobedience by urging farmers to plant new olive tree seedlings in the line of fire. All because the science of whether the bacterium is actually to blame for tree deaths in Puglia is not yet certain.

Italian officials have dispatched groups of forestry corps personnel, armed with chain saws, in response to a controversial European Union–backed eradication plan to ostensibly stop the deadly Xylella fastidiosa bacterium from spreading through Italy’s most productive olive oil producing region.

Xylella was first confirmed in the region in 2014 but scientists have yet to prove that it is uniquely responsible for the death of hundreds of thousands of olive trees south of Lecce in the base of the heel of Italy’s boot. Some olive trees in the area, known as the Salento, have been carbon-dated back 2,000 years. They are an integral part of the cultural heritage of the region, which extends far beyond agricultural productivity.

That’s why the uncertainty about the real effects of Xylella has led many tree owners and activists to question whether the extreme eradication plan is truly useful. They wonder out loud whether it is simply a way to placate the European Union, which has expressed concern that the destructive disease could spread north through Italy’s most lucrative olive producing regions and then farther, around the Mediterranean Sea and beyond.

The plan consists of cutting and burning both sick and healthy olive trees in a wide buffer zone north of Lecce to stop insects that carry the bacterium, which may be the reason it is spreading. Yet protests of the plan have arisen both on a grassroots and regional judicial level. There is no science, they say, to support the success of such an eradication plan (see sidebar). And local farmers are not embracing other recommended methods to fight the disease, including spot use of insecticides, because they think evidence does not exist to support those steps either.

And yet scientists on the front line in Italy say the battle cannot be won such without a comprehensive strategy that includes selective cutting, insecticides and other grove management practices. Chief among them is Donato Boscia, group leader of the Bari unit at the National Research Council of Italy's Institute for Sustainable Plant Protection, who first discovered the bacterium on his father-in-law’s trees. “It will take more than one weapon to win this,” he told Scientific American. “Without full cooperation, we will not succeed in saving any of Puglia’s olive trees.”

On October 12 the forestry corps started their chain saws to act on an eradication order to cut 3,000 trees in an area near the towns of Trepuzzi, Squinzano and Torchiarolo, north of Lecce. The tree owners had been given notice and a time limit by which they could cooperate. They could either voluntarily cut their own trees or allow forestry corps on their land and receive reimbursements for losses—or they would face fines of up to €1,000 ($1,130) for failing to do so.

By the end of the first day of this latest wave of cuttings, some 61 trees had been felled. An incredible 700 more are slated for eradication by the end of this week, according to regional authorities.

The regional agricultural minister, Leonardo di Gioia, urged everyone to work together. “Numerous growers have already received eradication notices; it is of vital importance that these be put into action immediately,” he said in a statement. “I urge institutions, business owners, growers associations and all who received the orders, without exclusion, to cooperate—with a sense of responsibility. Everyone's future is at stake, the future of Puglia.”

But on October 14, just two days after the cutting started, an Italian Regional Administrative Tribunal stepped in to demand that the chain saws be put down until at least November 4 while the tribunal considers a lawsuit lodged by 21 growers whose trees are slated to be killed. The growers say they should be given proof that Xylella is killing their trees before facing such extreme measures.

The judicial respite came with temporary permission for farmers who joined the lawsuit and whose trees are slated to be killed to quickly harvest their olives before the new November deadline. But Giuseppe Silletti, the special commissioner for the government in charge of the eradication, has demanded that his forestry corps continue to cut down the trees despite the judicial block. He warned that “the whole area will become a desert” like groves farther south in the Salento, where Xylella has been blamed for the death of many thousands of trees. Farmers in Puglia anxiously await November 4 to find out whether their trees will be given a stay of execution or face the chopping block.

People on all sides of this drama are operating with an alarming sense of tension and haste. On October 11 an olive tree owner in Torchiarolo who did not join the lawsuit, but whose trees were to be killed, said he would comply with the eradication order and cut dozens of his trees. But the activist group Popolo degli Ulivi took to social media and sent the message to its foot soldiers to rush to the farmer’s groves to stop him. They got there just in time, blocking the highway and with it the forestry corps members who were also rushing to help him complete the self-eradication once they heard of the activists’ plans. The activists convinced the farmer to stop.

The activists have also started crowdfunding efforts to raise the €1,000 fees for farmers who are fined for noncompliance. And they have urged all farmers in the eradication zone to plant new seedlings next to those destined to be killed as a symbolic act of civil disobedience, because all trees—no matter the age—are to be destroyed. Hundreds of seedlings have been planted so far.

Meanwhile, the French Ministry of Agriculture has just confirmed the first case of X. fastidiosa in continental France, after identifying it on the island of Corsica over the summer. The strain is different from the one affecting olive trees in Puglia, and so far it has only affected milkwort plants, which can be eradicated with little bother since they are ornamental wildflowers. But French officials are eyeing Italy warily. There is no evidence the strain will spread to grapes in France, but if it did, that would be just as devastating to the local culture as the destruction of olive trees in Puglia.

*Editor's Note (10/21/15): This article was edited after posting. The original version mistakenly referred to the Xylella fastidiosa bacterium as a virus.