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Despite late blight, Wisconsin’s potato crop will meet market demands for quantity and quality

News about late blight has raised concerns among retailers, processors
and other users about the availability and quality of stored potatoes
in Wisconsin this winter, reports A.J. Bussan, UW-Madison extension
vegetable specialist. But Bussan doesn’t think that either quality or
quantity will be a problem.

“The volume of stored potatoes does not appear to be in jeopardy due
to issues of late blight at this point in time,” he writes in a
newsletter article to growers. “All growers have been taking
preventative action to manage late blight since reaching critical
severity values 6 to 8 weeks ago and detections in production fields
have been limited to a single case. With vine kill actively ongoing
throughout the state and storage crop due for desiccation within days,
the threat of late blight decreases.

“Late blight cannot survive unless living potato/tomato tissue is
present. Growers are thoroughly scouting desiccated fields for any
signs of green tissue. Fungicide should continue to be applied if
stems or leaves remain viable or green after vine desiccation,” Bussan

Typically, about 80 percent of the state’s crop is put into storage
until needed by processors. The last time Wisconsin had a late blight
outbreak in potatoes was 2002.