The farmer drove a diesel-powered hay baler in a circuit around his field, followed by his son on a clattering machine that grabbed the bales with metal fingers.
Edward F. Stanfield, 77, and his son, Edward B. Stanfield, 49, have followed this oil-inspired choreography for decades on their 600-acre farm in the Randallstown area of Baltimore County.
Like farmers around the world, they grow their hay, corn and soybeans with petrochemical fertilizers and pesticides, harvest them with diesel combines, pack them with oil-based plastic and ship them in diesel trucks.
The mechanized "Green Revolution" the family joined after World War II created an explosion in food productivity that allowed global populations to multiply. But it also forged a dependence on oil that could now lead to a food crisis, a small but growing number of scholars and activists warn.
Dr. Brian Schwartz, co-director of the program on global sustainability and health at the Johns Hopkins Bloomberg School of Public Health, said governments should start planning for a worst-case scenario, with soaring oil prices disrupting food supplies, just as they plan for other possibilities like nuclear war and bioterrorism.
"We have an industrial model of food production that requires intense amounts of fossil fuels," Schwartz said. "Food is going to be a huge problem for us."
Dale Allen Pfeiffer, author of the recent book Eating Fossil Fuels: Oil, Food and the Coming Crisis in Agriculture, goes even further in his warnings. With global oil production soon sliding into decline, fuel prices might continue to skyrocket until the world's food system collapses, causing starvation, he wrote.
"Growing evidence indicates that world [oil and gas] production will peak around 2010, followed by an irreversible decline. The impact on our agricultural system could be catastrophic," he wrote. "Hunger could become commonplace in every corner of the world, including your own neighborhood."
Pfeiffer estimated that the U.S. population of about 300 million is roughly a third larger than can be fed with the gradually shrinking oil supply expected over the next half-century. As a comparison to the agricultural crisis the world faces today, he noted, "The black plague during the 14th century claimed approximately a third of the European population, plunging that continent into a darkness from which it took them nearly two centuries to emerge."
The surge in oil prices has already hurt the Stanfield farm's output. As fertilizer costs doubled and diesel prices spiked, Edward B. Stanfield said, he'd had to grow less corn this year.
"It all goes up," he said of prices linked to oil. "There is no way to escape [oil], unless we're going to go back to the horse-drawn days, and I don't think we can survive with the number of people we have in the world today," he said, watching his father drive a tractor down a long row of cut hay.
The idea of starvation triggered by oil prices sounds outlandish - and indeed, it is dismissed by many economists, farmers and petroleum producers.
John Felmy, chief economist at the American Petroleum Institute, said the world's oil supply would not decline at any foreseeable time. The only risk of economic collapse and hunger, he said, will come if the government tries to intervene with price controls. Felmy said that more offshore oil drilling, as advocated by President Bush last week, could help with oil and food prices.
"Economists say you never run out of anything - it's just how costly it gets," said Felmy. "Technology continues to improve, and we continue to find new sources of oil. There is every indication that there is sufficient oil in the ground that could be recovered."
Schwartz, of Johns Hopkins, said statistics compiled by well-respected petroleum geologists suggest that this picture of plenty is misleading. He said a critical mass of experts is predicting that petroleum production will shrink in the next few years because new oil discoveries have been declining since the 1960s, despite increased exploration. Meanwhile, demand for fuel will continue to rise rapidly in the expanding economies of countries such as China and India.
Falling production will accelerate the already soaring price of fuel, to the point that it's too expensive for average consumers and farmers, Schwartz said.
It's not that the world will literally run out of oil, Schwartz said. Some oil will always remain in the ground. The problem is that petroleum is a limited resource, and oil production always follows a bell curve, with a peak and then an inevitable dropoff, he said.
More reliance on low-grade tar sands or harder-to-reach oil will cost more, contributing to price escalation. Increased drilling of known oil fields, such as those in Alaska or off the California coast, will only temporarily delay the fundamental dynamic of surging demand but less coming out of the ground, Schwartz said.
This problem of "peak oil" was first outlined by Shell Oil's research director M. King Hubbert during the 1950s. He was ridiculed when he predicted in 1956 that the United States, then the world's biggest source of oil, would experience a production peak between 1966 and 1972, followed by decline.
But Hubbert was proved right when oil production in the lower 48 states peaked in 1970 and then started to drop, despite increased drilling, Richard Heinberg wrote in The Party's Over: Oil, War and the Fate of Industrial Societies.
Canada's oil production peaked in 1974, Egypt's in 1993, Syria's in 1995, Ecuador's in 1999, Yemen's in 2001 and Mexico's in 2004, among other countries now in decline. Overall, oil production is past peak in 33 of the world's 48 largest oil-producing companies, according to data compiled by Schwartz.
Even Saudi Arabia, with the world's largest petroleum reserves, may have peaked. The kingdom is pumping increasingly large amounts of water into the globe's largest oil field, called Ghawar, trying to get the remaining fuel out if it, industry historian Matthew R. Simmons wrote in Twilight in the Desert: The Coming Saudi Oil Shock and the World Economy.
Simmons, a former oil adviser to Vice President Dick Cheney, is no tree-hugging alarmist. But he says Saudi oil production "is likely to go into decline in the very foreseeable future."
The well-known oil investor T. Boone Pickens concluded that the world passed its peak oil production in 2005, echoing the rough time frame laid out by Hubbert and several oil geologists. Even the buttoned-down investment firm Merrill Lynch has predicted that world oil production will peak in 2015.
To plan for this inevitable downturn, nations must quickly shift toward renewable fuels, including solar energy and wind, Schwartz said. The United States must start to conserve energy and change living patterns so that people no longer commute from sprawling suburbs. People need to walk to work, use mass transit and start eating food from local farms so they don't depend on fish and fruit flown in from Asia and South America, he said.
"Countries are not prepared for this at all," Schwartz said. "And because they are not prepared, they will tend to go toward temporary solutions like burning more coal and oil shale that will only make climate change worse."
It's possible that an oil shortage could mean better health. When petroleum supplies were cut off to Cuba in 1989 because of the fall of the Soviet Union, Cubans had to start walking and biking to work and farming in their neighborhoods. The nation's obesity rate dropped by half, and fewer people died of heart attacks and diabetes, said Dr. Manuel Franco, another Johns Hopkins researcher.
Still, replacing oil isn't easy. It's more dense with energy than most alternatives. Burning one barrel (42 gallons) provides the same energy as 12 farm laborers working every day over a year.
The Stanfields burn the equivalent of about 1,400 gallons a week in their diesel-powered tractors and combines during harvest. With cheap oil, father and son have been able to work the fourth-generation family farm as a twosome. But without diesel, they would need scores of field workers.
Although Americans are keenly aware of rising fuel prices, Edward B. Stanfield doesn't believe they're yet ready to trade in golf clubs for scythes.
"It would take hundreds of people with back-breaking work to operate this farm," Stanfield said. "And where would these workers come from? Our society today is lazy. People just want to go to the store and buy their food. They don't want to know where it comes from."