It's harvest time for many in the potato industry, and for those not quite to that point, harvest will be here before you know it. And while many growers are thinking about getting those spuds in a storage shed or off to the processor, Washington State University’s Tim Waters says growers need to continue to watch for pests. He says pre-harvest insect pressures have been fairly low, but that does not mean growers are in the clear. Waters says growers need to be very cognizant of potato tuber moth.
“Potato tuber moth is not a problem when the vines are green, because the larvae will mine in between the leaves and on the stems, and that does not cause economic damage,” says Waters. “The problem occurs when the foliage is killed: The moth larvae will go down and feed on the tubers, which causes big problems when you go to put those into storage or run them through a processing plant.”
What do growers need to do? Waters says it’s important to monitor each individual field for tuber moth, using pheromone traps placed upwind.
“If you get a few per night, that’s usually not of concern,” he says. “But when you start to get 10, 15, 20 per night, that’s really a concern, and growers need to think about making an insecticide application to protect the crop.”