WINNIPEG, Manitoba (Reuters) - Killing frosts hit crops in northwestern Alberta late Tuesday, but a widespread frost across the Prairies looks to arrive a day later than expected, a Canadian Wheat Board analyst said Wednesday.
Frost is of particular concern to Western Canadian farmers this year because many crops are one to two weeks behind normal growth, leaving them vulnerable to damage that reduces quality. The harvest of all crops is moving at its slowest pace in six years due to rainy weather, with less than one-quarter finished as of Monday.
Killing frosts, which halt the growth of plants when temperatures fall below minus 2.2 degrees Celsius (28 degrees Fahrenheit), settled into Alberta's Peace region, a major grower of wheat and canola, said Stuart McMillan, the Wheat Board's crop and weather analyst.
A small pocket of northwestern Manitoba around Grandview also had killing frost.
A more widespread killing frost looks to arrive Friday morning in Alberta and spread east, one day later than the Wheat Board forecast on Monday.
"It's looking like it might be not as severely cold (as thought earlier)," McMillan said. "The downside is there's still a very good chance of rain coming through and farmers are not going to get a real good chance (to harvest crops)."
Killing frost might miss some southern areas altogether this weekend, McMillan said, adding that temperatures look warmer next week.
Canada is the top exporter of spring wheat, canola and rapeseed and a key shipper of oats.
A killing frost freezes the moisture in immature wheat kernels, causing them to rupture and shrivel, McMillan said.
In immature canola, frost halts growth with seeds still unripe, which lowers its value.
Editing by John Picinich