Driving his tractor through a windy field at the feet of western Canada's Rocky Mountains, Doug McBain spreads small white pellets and canola seed into the freshly turned soil.
This is no ordinary farming process. McBain is testing a new form of fertiliser that could help rejuvenate crops by returning sulphur - one of the biggest by-products of oil and gas production - back to the earth.
Sulphur is essential for healthy crop growth and occurs naturally in food such as onions and eggs. Yet its combination with other elements can create dangerous compounds such as hydrogen sulphide.
Companies helping to meet rising energy demand are tapping into oil and gas fields with higher levels of the bright yellow chemical. Tighter regulations also mean more sulphur must be removed from transport fuel before it can be burned.