Last-minute planning, forced by delays in releasing irrigation water, and a late spring created conditions ideal for pest proliferation, said Brian Charlton, cropping system specialist with the Oregon State University Klamath Basin Research and Extension Center.
Potato farmers who didn't receive surface water allotments at the beginning of this planting season had to lease fields that had access to water, many of which aren't ideal for potatoes. That combined with prolonged cool, wet weather allowed seed corn maggots and wireworms to feed on potato seed pieces and young plants.
Land in Langell Valley and Bonanza, which hasn't grown potato crops for a long time, has been particularly problematic, Gasser said.
"That's the nature of the beast," said Bob Gasser, co-owner of Basin Fertilizer and Chemical Co. in Merrill. "People were going into ground they don't normally go into with no time to prepare the ground.
"It's the last-minute decisions everyone had to make this year."
The pests
Seed corn maggots, the larval stage of the common fly, thrive in areas that are cool, moist and have vegetation to feed on.
Many farmers this year didn't have time to prepare leased fields - oftentimes permanent pasture ground - for planting, so there were remnants of previous uses, including fly eggs and vegetation, in the dirt when the seed pieces were put into the ground, Charlton said.
The maggots feed on seed pieces, making them vulnerable to fungi and bacteria.
Wireworms, the larval stage of common black beetles, attack more mature plants by burrowing into newly formed tubers, making holes in the potato. The extent of that damage won't be evident until after harvest, Charlton said.
"We historically haven't had too much trouble with that pest, so a lot of growers went to backup ground in the spring and didn't do bait testing. It came to light when they found (wireworm) on seed pieces," Charlton said.