There have been no confirmed cases of late blight to date in Ontario.
The late blight infected potato field detected in Michigan on June 21 was burned and disked very quickly. No late blight symptoms were found in surrounding fields. As previously reported, late blight has also been found in east-central Ohio and northwestern Pennsylvania, as well as in several states further south.
Weekly updates about late blight in New York and the contiguous states and Canadian provinces can be found at http://nysipm.cornell.edu/scouting/late_blight/default.asp.
A model predicting favourable weather conditions for late blight infection in North America can be found at: http://uspest.org/risk/tom_pot_map. This only indicates favourable weather conditions, and not the presence of the pathogen. Without late blight inoculum, the disease will not develop even in highly favourable conditions.
You can click on a “pin” on the map to get more details and customize the information. The environmental conditions within an individual field may differ from the macro level conditions reported here.