Prince Edward Island Seed Potato Export to the United States halted - again - due to Potato Wart

The U.S. border has closed to Prince Edward Island seed potatoes after potato wart was again found in two P.E.I. fields, the Canadian Food Inspection Agency confirmed late Friday.

The CFIA confirmed potato wart in fields on two separate farms on Oct. 1 and Oct. 14 after growers submitted "suspect potatoes," the agency said in an email response to a CBC inquiry.

The potato wart fungus is spread through the movement of infected seed potatoes and contaminated soil.

It poses no threat to human health or food safety, but is known to decrease yield — the number of good potatoes that can be harvested and sold.

The CFIA took immediate action to impose control measures on the affected fields, it said, to prevent the spread of the fungus.

Although no potatoes from either farm have been shipped outside of the province, the release said seed potato shipments from P.E.I. to the U.S. have been "temporarily suspended."

The movement restrictions do not apply to fresh P.E.I. potatoes for table stock or processing, which continue to be exported domestically and internationally.

Same thing happened last year

Trade of seed potatoes between P.E.I. and the U.S. was shut down in 2000 when potato wart was first found on the Island.

Since then, new protocols have been introduced for monitoring and controlling the spread of the fungus, and there were no trade issues after subsequent discoveries of the fungus, including in 2012 and 2014.

The border closure in 2000 cost P.E.I. potato farmers $22 million in sales.

About 15 per cent of potatoes grown on P.E.I. are used for seed.

The United States has been the single biggest international buyer. In 2019, $3.1 million of $4.5 million in seed potato exports went to U.S. buyers.

The interprovincial and international trade of seed potatoes from P.E.I. represents approximately 2.1 per cent of all P.E.I. potato production when measured by volume, the CFIA said.

"These actions are being taken in order to maintain our markets, including the U.S. market, for table and processing potatoes," the email said. "Specific country import requirements from P.E.I. to all other destinations are currently being evaluated, based on the requirements of different countries as it relates to potato wart."

If this sounds familiar, it is: in October 2020, potato wart was discovered in two fields in Queens County, after routine export soil testing identified the fungus in the fields, about 20 hectares on the same farm. Exports were halted to the U.S. as a result. Those fields were retested and the CFIA found them to be wart-free in February, 2021. The export ban was lifted March 11.

Potato wart can remain dormant in a field for more than 20 years.