MADAN HERI, INDIA (WASHINGTON POST) - All it takes is a match.
One by one, in the coming days, farmers in this compact village in northern India will set fire to the straw in their freshly harvested rice fields.
Pungent gray smoke will rise into the air. Then it will drift south-east towards New Delhi, thickening the smog that has turned India's capital into the most polluted major city in the world.
Just weeks remain before the 29 million people living in greater Delhi are plunged into their annual battle with extreme air pollution.
Each November the past two years, the level of particle pollution considered most harmful to human health has spiked to more than 30 times the limit prescribed by the World Health Organisation. The air in the city remains hazy and dirty throughout the winter.
The Indian government has a new action plan in place: It just shuttered the last coal-fired power plant in Delhi and recently banned the use of certain industrial fuels within the city.
On days when the pollution soars, other measures will kick in, such as a halt to all construction activities and a ban on trucks entering Delhi.
But turning the tide in the fight against pollution will depend on efforts such as the one now underway in the state of Punjab, the powerhouse of Indian agriculture.
There the authorities are engaged in a race to persuade farmers not to torch their fields, urging them to shun a tactic that is cheap and efficient in readying the area for the next crop, but that is also a key source of pollution.
The smog that blankets northern India each winter is a toxic mix of car exhaust, construction dust and industrial emissions that settles over the region as wind speeds and temperatures drop.
What makes it unusual is the addition of smoke from thousands of fires as farmers hurry to switch their fields from fully grown rice to newly planted wheat in the span of a month.
"The uniqueness of the smog season is precisely because crops are being burned at an unheard-of scale anywhere else in the world," said Mr Siddharth Singh, author of the forthcoming book The Great Smog of India.
According to a government-sponsored study, stubble burning contributed 26 per cent of the most harmful particulate matter to Delhi's winter pollution during 2013 to 2014; another found it contributed as much as 50 per cent on certain days during the burning season.
Such particulate matter - referred to as PM2.5 - is 30 times as thin as a human hair and can penetrate deep within the lungs.
The task of dissuading the farmers from burning is a microcosm of India's broader pollution challenge.
Unlike China's authoritarian regime, which has made strides in recent years in stemming air pollution, India must operate within the constraints of a democratic system.
Reducing the sources of pollution in India involves confronting entrenched interests, overcoming political rivalries and motivating people to change their behaviour.
China has been able to "maintain the scale and momentum of action", said Ms Anumita Roy Chowdhury, an executive director at the Centre for Science and Environment in Delhi.
"In India, you have to make democracy work for clean air."
That's especially true in the case of crop burning. Farmers are a powerful constituency in Punjab and in other straw-burning states such as Haryana, and there are roughly two million farmers in Punjab alone.
"The number of farmers is so large that we cannot take very harsh measures," said Mr Kahan Singh Pannu, agriculture secretary in Punjab.
A senior bureaucrat known for his tough approach to polluters, Mr Pannu is leading the anti-burning efforts in Punjab.
He has mostly carrots, not sticks, at his disposal. For the first time this year, India's central government earmarked money to help farmers buy machinery that turns the straw into mulch.
It has also contributed to a large-scale awareness campaign, complete with songs on social media, television advertisements and village-by-village meetings - all urging farmers not to burn.
Mr Gurdial Kumar is one of the foot soldiers in the statewide effort. A 48-year-old employee of the Punjab agriculture department, he and his colleagues began visiting each of the 182 villages in their territory last month.
On a recent afternoon, they arrived in Madan Heri, a village of 2,500 people west of Chandigarh, where about 20 farmers had gathered in the shade of a giant banyan tree.
Mr Kumar and his three colleagues put up posters illustrating the impact of air pollution, including images of diseased lungs and small children wheezing.
They talked about the virtues of the new subsidised machines, including one called the "Happy Seeder".
They appealed to religious precepts; most of the farmers practice Sikhism, whose sacred text emphasises the holiness of nature.
The farmers listened politely but without enthusiasm. Then they launched into questions: How about simply paying farmers a fee per acre not to burn their fields? Why was the government asking small farmers, already financially strapped, to scrape together cash for new machines? If they invested in the machines - which cost about US$2,000 (S$2,751.40) each - when would the government pay the subsidy, equivalent to half of the cost?
Mr Gurtej Singh, 42, said he had farmed - and burned - these fields for more than two decades.
He agreed that setting fires is bad for the environment, but said that dealing with the straw using other methods is more expensive and time-consuming.
"Small farmers can't do it," he said.
He rejected the blame for Delhi's pollution, a common theme among farmers in the area.
Pollution in the capital "is because of vehicles and industry, not because of us", he said.
Farmers did not suffer any ill effects from the crop burning, he asserted. Pollution-related health issues are "a problem of weak people in cities".
Farmers in nearby villages echoed those sentiments.
"Burning is the best solution," said Mr Darshan Singh, 43, as green-tipped rice swayed in the fields behind him. "Whatever machine you use, you have to pay more."
But the government's campaign was having an impact. Mr Darshan Singh was cagey when asked whether he would burn his crop stubble this season.
"Whatever other people do, I will also do," Mr Singh said.
Crop burning is technically banned. If farmers are caught setting fire to their fields, they face fines ranging from US$35 to US$140. In rare instances, some have also faced criminal charges.
"It's not that these are poor, illiterate, information-starved people who are doing a bad thing and if only we educate them, they'll do the right thing," said Dr Aseem Prakash, director of the Centre for Environmental Politics at the University of Washington.
"If people are really serious about tackling (the problem), they have to come up with an economically viable solution."
The trend is moving in the right direction. According to the Punjab government, there were 81,000 fires after the rice harvest in 2016, then the figure dropped to 44,000 in 2017.
Through Friday, there had been 509 fires this year - but the crucial period for burning will come later this month.
Mr Jagdeep Singh, 38, a farmer in Simbal Majra who cultivates 65 acres, just bought a Happy Seeder machine and plans to use it for the first time this month.
The machine cuts the rice straw, spreads it as mulch and sows wheat seeds.
He, too, was closely watching the actions of the state authorities to gauge the seriousness of their campaign against crop burning.
"It seems there will be less fires this year," he said.
"But if the government gives a little relaxation" - he flicked his fingers upward in a flame-like motion - "it will all be done in one day."