More traps to be set in
basin for pest
By HOLLY OWENS H&N Staff Writer
TULELAKE — More traps for
potato tuberworm moth will be set in fields
around the Klamath Basin this year in an effort
to track and research the newly found pest.
The Klamath County Extension
Service through Oregon State University will set
some traps, with funding help from the Oregon
Potato Commission.
Potato growers are encouraged
to set their own traps as well.
“This year we’re hoping for a
much better look at what’s going on in the
Basin,” said Kerry Locke, a Klamath County
extension agent, during a seminar for potato
growers Feb. 16 at the Tulelake-Butte Valley
Fairgrounds.
Pheromone-baited traps, which
attract male tuberworm moths, will be used to
monitor the pest’s population.
“You have to have a trap in
your own field, and we certainly recommend
that,” said Philip Hamm, plant pathologist and
superintendent of the Hermiston Agricultural
Research and Extension Center of Oregon State
University.
No standardized recommendations
exist for pesticide application, but research
done in northern Oregon’s Columbia Basin
suggests one treatment for adult moths has been
found to be as effective as several applications
throughout the season.
“One application at the end of
the season had the same impact,” Hamm said.
“When you treat those fields you just knock them
down
with pyrethroids.”
The adult moths are easy to
kill, Hamm said, but with more than one
generation developing during a growing season,
the pest is proving persistent.
“They come back because there
are two or three other life stages you need to
worry about,” Hamm said.
Keeping the soil moist, thereby
preventing cracked soil, eliminates an entry
point for female moths,
which lay eggs on the eyes of tubers.
Weeding out volunteer potato
plants in newly established grain, hay and
alfalfa fields that have previously grown
potatoes was another recommendation for growers
to help slow down the spread of tuberworm moth.
Packing sheds face another
problem: How to prevent the pest from spreading
to neighboring fields from packing shed
operations. Packing sheds in the area bring in
potatoes from the Columbia Basin, which has been
coping with its own tuberworm infestation.
The biggest priority, Hamm
said, is taking care of potatoes culled during
packing.
There should be no storage of
cull piles.
“If you pack them out right
away and don’t have a cull pile you shouldn’t
have a problem,” he said.
To stop tuberworm egg and pupae
development in stored potatoes, Hamm recommended
keeping crops at a temperature between 50 to
58.2 degrees.
But in some colder regions, the
tuberworm threshold has been known to be a few
degrees lower.
“It’s less than 50 degrees
which makes it different, seemingly, than the
population in California,” Hamm said.
For seed growers, Hamm said
potatoes with tuberworm will most likely be
detected before they make it to the field.
Through culling done by grower, packer and
customer, infested tubers, which are subject to
rot due to tuberworm tunneling, are taken out of
production.
Once the seed potatoes are planted, the
tuberworm would need to travel 8 to 10 inches
just to get out of the ground.
“I don’t think they get out of
the ground. I don’t think it’s an issue,” Hamm
said.
Once research is complete, Hamm
believes the tuberworm moth will become less of
a problem, and it will be just another one of
several pests and diseases potato farmers
routinely deal with.
For information, call the
Klamath County Extension Service at 883-7131.