"The amount of marihuana produced in Canada exceeded domestic demand. Reportedly, there were OC [Organized Crime] groups producing this drug specifically for export to foreign markets, the largest of which is the United States. According to the U.S. National Drug Intelligence Center (NDIC), while seizures of Canadian marihuana have declined13 at the Canada-U.S. border, Canada continued to be a source country for high-grade marihuana destined for U.S. illicit drug markets.v The reported decline was believed to be due, in part, to Canadian-based Asian OC groups using their expertise to establish cannabis cultivation sites within the United States, thereby avoiding the cost of transporting drugs across the border and the risk of detection.
"Shipments of marihuana destined for Canada were smuggled through air cargo or passenger flights, and arrived primarily at Toronto Pearson International Airport. Canada Border Services Agency (CBSA) reported the seizure of approximately 1.15 tonnes of marihuana in 2009, with 60 percent of the total originating from Jamaica. Jamaican marihuana was primarily supplying a small market in Ontario and Quebec."

Source

RCMP Criminal Intelligence, "Report on the Illicit Drug Situation in Canada - 2009," Royal Canadian Mounted Police (Ottawa, Ontario: 2010), p. 17.
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