Canada will challenge what Ottawa described as an "unfair, unjust and illegal" extension of U.S. import duties on Canadian softwood lumber products, the trade ministry said on Tuesday. The softwood lumber tariffs are the legacy of a decades-long trade dispute over the structure of Canada's timber sector that could not be resolved when a quota agreement expired in 2015. U.S. producers say Canada unfairly subsidizes its lumber sector. The U.S. Commerce Department in July set a duty rate of 7.99% on the product. Canada on Monday filed notices of intent to ...