In northern climates where early frosts and short growing seasons can be a problem, many people probably think global warming would be a plus for agricultural crops. Recent research indicates that will not be the case, at least not for forage crops.
Proving that it's the result of global warming may be difficult, but there can be no disputing the fact that winter temperatures in many areas on the rise. Some scientists now say this change will actually increase a plant's exposure to freezing temperatures.
Scientists from Agriculture and Agri-Food Canada predict crops will be at greater risk of winter damage in the future even though the climate will be warmer. Perennial forage crops are grown on more than 40 per cent of the cultivated land in Eastern Canada and other regions of North America.
The loss of snow cover due to warmer winter conditions will increase exposure of plants to freezing temperatures. Forage crops are also likely to enter the winter in a lower state of cold hardiness due to warmer fall temperatures.
Winter temperatures are expected to increase by two to six degrees celcius over the next 50 years in Eastern Canada, but the survival of perennial crops over the winter months requires the right climatic conditions.
Gilles Bélanger, the leader of this research project, said, "This might be a surprise to many that warmer winter conditions will mean greater risks to perennial forage crops. Perennial forage crops in Canada and in the northern part of the United States prefer the comfort of a nice snow cover after a good rest period in the fall. Rain, ice, and no snow cover in the middle of the winter will occur more often in the future."