The latest trapping results for the Eastern and Western Aroostook region are now available for the 7-day period ending June 17. All fields are currently being sampled once per week.
You can access the results by clicking the link below. The data is provided in an Excel file. Once opened, use the tabs at the bottom labeled with township names to view specific results for areas of interest.
Notably, eight traps within the Central Aroostook area had positive detections for Late Blight spores. Traps in Mars Hill, Fort Fairfield, Limestone, Caribou, Crouseville, and Washburn had detections. I would urge caution with quantitatively interpreting spore numbers. There are many factors that could affect spore number, including site location, elevation, proximity to the source, and surrounding vegetation. Interpretation should be limited to qualitative presence/absence or trends over time.
The earliness of this detection likely means that the source is local and likely originating from a cull pile or in field(s) as a seedborne issue.
The deadline for cull potato disposal was June 10th. Following the best management practices for managing cull piles is essential to reduce the spread of potato diseases such as late blight. If you are aware of unmanaged cull piles, please report them to Matthew Randall, Agriculture Compliance Officer, at 207-557-0252 or matthew.randall@maine.gov.
Although as a whole industry we are just past 50% emergence and forecasting hasn’t surpassed the 18 DSV initiation point, I urge all Central Aroostook growers to consider initiating late blight protectant fungicide sprays on anything that has emerged at this point.