Although genetic testing has confirmed zebra chip in only three Idaho Falls County and one Minidoka County locations, plants with symptoms have been collected or reported from several other Idaho locations.
Potato psyllids also continue to be trapped at several sites across the state being monitored by the University of Idaho, according to a pest alert.
Many of those psyllids tested positive for Candidatus liberibacter, the organism responsible for zebra chip.
University researchers have yet to find any immature psyllids on leaf samples.
And they encourage growers and consultants to continue aggressive scouting.
Zebra chip, which is harmless to humans, changes the way potato tubers store sugars.
When the potatoes are heated, such as during frying, the sugars caramelize, creating undesirable brown stripes.
For more information on psyllid management and zebra chip, download the 8-page informational booklet from Pacific Northwest Extension.