MAASLAND, Netherlands (AP) — Bales of hay lie burning along Dutch highways. Supermarket shelves stand empty because distribution centers are blocked by farmers. Then, at dusk, a police officer pulls his pistol and shoots at a tractor.

Dutch farmers are embroiled in a summer of discontent that shows no sign of abating. Their target? Government plans to rein in emissions of nitrogen oxide and ammonia that they say threatens to wreck their agricultural way of life and put them out of business.

The reduction targets could radically alter the Netherlands' lucrative agriculture sector, which is known for its intensive farming, and may also foreshadow similar reforms — and protests — in other European nations whose farmers also pump out pollutants.

That turmoil seems a long way off Friday at Jaap Zegwaard's dairy farm, which occupies 80 hectares (200 acres) of grassland close to the port city of Rotterdam, whose chimneys and cranes form a backdrop to his fields.

Most of Zegwaard's herd of 180 cattle, mostly black and white Holstein-Friesians, graze in meadows close to a traditional Dutch windmill and large white wind turbines. And even if the farm has been in Zegwaard's family for five generations, some 200 years, he doesn't know if he would recommend the farming life to his a 7-year-old daughter and 3-year-old twin boys.

“If you ask me now, I'd say, please don't even think about it," the 41-year-old said. “There are so many worries. Life's much too beautiful to deal with what's going on in the agriculture sector at the moment.”

“Ask the average farmer: it's profoundly sad,” he said.

At the heart of the clash between farmers and the Dutch government are moves to protect human health and vulnerable natural habitats from pollution in the form of nitrogen oxides and ammonia, which are produced by industry, transport and in the waste of livestock.

The Netherlands, a nation of 17.5 million people inhabiting an area a little larger than Maryland, has 1.57 million registered dairy cattle and just over 1 million calves being raised for meat, statistics show. The country's farms produced exports worth 94.5 billion euros in 2019.

Nitrogen oxides and ammonia raise nutrient levels and acidity in the soil, leading to a reduction in biodiversity. Airborne nitrogen leads to smog and tiny particles that are damaging to people's health.

When the Council of State, the country's top administrative court and legislative advisory body, ruled in 2019 that Dutch policies to rein in nitrogen emissions were inadequate, it forced the government to consider tougher measures.

Unveiling a map detailing nitrogen reduction targets last month, the Dutch government called it an “unavoidable transition.” It said the coming year would finally bring clarity for Dutch farmers, “whether and how they can continue with their business. The minister sees three options for farmers: become (more) sustainable, relocate or stop.”

The Dutch government aims to slash nitrogen emissions by 50% by 2030 and has earmarked an extra 24.3 billion euros ($25.6 billion) to fund the changes. Provincial authorities have one year to draw up plans for achieving the reductions.

Nitrogen expert Wim de Vries, a professor at Wageningen University and Research, doubts that deadline is realistic.

“It seems to be very fast and there is a legacy, already for 40 years, because the problem was much bigger in the 1980s. We then called it ‘acid rain,’" he said. "Considering that legacy, it doesn’t make so much difference if we do it in 7 or 10 or 12 years. We anyhow have to wait for decades for nature to improve seriously.”

Farmers have been protesting for years against the government's nitrogen policies, but the emissions targets unleashed new demonstrations, with tractors clogging highways and supermarket distribution centers that led briefly to some shortages of fresh produce.

Farmers also clashed with police outside the home of the minister in charge of the government's nitrogen policies. And this week an officer opened fire on a tractor driven by a 16-year-old. After initially being held on suspicion of attempted manslaughter, the young driver was released without charge.

The Dutch government has appointed a veteran political negotiator to act as a middleman, but the gesture was immediately rejected by activist farmers and the nation’s largest farming lobby group.

“The government does not offer any space to enter into a real conversation,” said the farming lobby group LTO. “Under these conditions, speaking with the mediator is pointless.”

The LTO, which represents about 30,000 farms — nearly a half of the Dutch total — described the nitrogen reduction target as “simply unfeasible.” Dutch farms produced exports worth 94.5 billion euros in 2019.

The group says the government is focused on reducing livestock and buying up farms and not paying enough attention to innovation and sustainable farming practices.

Environmentalists say now is the time to act.

“You rip a plaster off a wound in one go," said Andy Palmen, director of Greenpeace Netherlands. “Painful choices are now necessary.”

Zegwaard's farm is in an area where the government is seeking only a 12% cut in emissions, yet he also demonstrates out of solidarity with others and supports the protests.

“The average person currently sees the Netherlands as a nitrogen polluter, while we are also a food producer. It seems like people have forgotten that," he told The Associated Press.

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