Moscow, Idaho
August 5, 2009
A new computer program developed
by University of Idaho weed
scientists is designed to simplify herbicide selection and
prevent development of herbicide resistant weeds and damage to
future crops.
Weed scientists Donn Thill, Joan Campbell and Traci Rauch
developed the program for dryland farmers in northern Idaho,
eastern Washington and eastern Oregon. Weed scientist Don
Morishita at the Kimberly Research and Extension Center is
working to expand the program's use to southern Idaho irrigated
crop rotations.
"The goal is to help growers make decisions about which
herbicide might best control weed problems and fit into their
crop rotations," said Thill, a professor of weed science and
superintendent of the Palouse Research, Extension and Education
Center at Moscow.
The program, "Herbicide Resistance and Persistence Management,”
is available on a free trial basis to growers. Growers who
decide to use the program will be charged a $50 annual
subscription fee to cover updates.
The program combines two of the College of Agricultural and Life
Sciences' most popular publications into a dynamic program that
can provide more frequent updates than printed offerings, Thill
said.
Tracking and adjusting herbicide use is essential to controlling
resistance in weeds. Over 200 weeds worldwide now show
resistance to commonly used herbicides. Thill and Campbell have
been leaders in helping Northwest growers plan strategies to
limit herbicide resistance in weeds.
The main way to avoid resistance is to change herbicides based
on their modes of action on weeds.
Growers can face substantial challenges in both trying to use
herbicides from different groups to control common weeds and
then keeping clear records through multiple seasons.
The University of Idaho's herbicide management program can help
accomplish both tasks.
In addition, the program targets another challenge for growers,
deciding which herbicide best fits their crop rotations. Some
herbicides can persist in the soil for more than a year in
concentrations high enough to damage future crops that are
especially susceptible to damage.
The backbone of the program is manufacturer's labels required by
federal law for all herbicides. The label information contains
directions on which crop the herbicide is registered and
directions on how to use it.
The program's data files contain all herbicides and their uses
in Pacific Northwest dryland, or non-irrigated, agriculture that
have been registered by the U.S. Environmental Protection
Agency, a massive undertaking. Multiple crops and rotations made
a computer program the best option for growers, Thill said.
The database tracks label directions on herbicide persistence
for up to five years, although in most cases the effects are
gone in a year. Some crops, however, can suffer herbicide injury
several years later. In rare instances, Thill said, unique soil
conditions could extend herbicide persistence but common sense
made five years seem a logical limit.
Thill said the weed scientists plan to update the database twice
each year to keep the data as current as possible. The program
is available for purchase online at
www.cals.uidaho.edu/herbicidemanagement. Growers who download
the program will have a six month trial period before they have
to pay a subscription fee.
The program's development was funded by the Idaho Wheat
Commission, Idaho Barley Commission and University of Idaho
College of Agricultural and Life Sciences.
Written by Bill Loftus |
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