Bulletin E-Edition:
Adult cereal leaf
beetles like this one eat through leaves of cereal plants and grasses, sometimes reducing farmers’ crop yields by 75 percent.
Photos courtesy Oregon Department of Agriculture
Area farmers battle beetles with wasps
By Jeff McDonald / The Bulletin
Published: August 04. 2006 4:00AM PSTCentral Oregon farmers are experimenting with new ways to battle a crop-eating pest, the cereal leaf beetle, that has worked its way across the nation.
The beetle, which feeds on grasses and the leaves of cereal crops - including spring and winter wheat, barley and oats - reached Oregon in 1999 and now infests about half the state's counties.
Insecticides are effective, but expensive, costing about $10 to $15 per acre, agricultural officials say.
Farmers on the East Coast and in the Midwest have virtually eliminated the beetle naturally by introducing a predator: the Tetrastichus julis, a tiny parasitic wasp.
Central Oregon farmers are using the wasps for the first time this year.
The stakes are big. Infestation can reduce a crop's yield by 60 percent to 75 percent if not caught early, said Mylen Bohle, an agronomist with Oregon State University Extension.
Throughout the state, growers spent $602,100 in 2005 on 50,175 acres to combat the beetle with insecticides, according to the state's Department of Agriculture.
Farmers grow between 10,000 and 20,000 acres of cereal crops in Central Oregon, Bohle said.
Approximately 660 acres were treated with insecticide in Jefferson and Crook counties in 2005.
Now, more farmers are turning to biological control through wasps as a more natural and affordable way to combat the beetles.
The wasps, so small that they're barely visible, attack the larval stage of the cereal leaf beetle. Upon hatching, the baby wasps kill the beetle's larvae, Bohle said.
"The beetle can do a tremendous amount of damage," he said. "Without treatment, the beetle could potentially impact a couple hundred producers."
Researchers at Central Oregon's Agricultural Research Center, or COARC, in Madras have set aside 5 acres for an insectary to breed the wasps and cereal leaf beetles.
They need to breed the pair together because the beetles' larvae serves as the food source for the wasps, Bohle said.
"In other states, they no longer have to spray for the cereal leaf beetle," he said. "I see no reason why it won't work here."
Through a cooperative project between the state and federal departments of Agriculture, OSU and COARC, small populations of wasps were released into two small fields in Culver and Madras in June.
The owner of a field in Madras, Bob Crocker, will know how much damage the beetle did when he harvests his wheat crop next month. He became one of the first Central Oregon farmers to employ the biocontrol methods on his field.
Crocker doesn't know how many acres of his 40-acre wheat field were lost due to the cereal leaf beetle.
"We've never had damage like this before," he said. "Hopefully, we won't have a problem from now on."
Rex Barber Jr., owner of Big Falls Ranch in Culver, experienced isolated infestation of the beetle this year. He spent approximately $800 on insecticides to treat one 40-acre field this year, but likely will release the wasps next year.
"We haven't had general infestation, but it's very likely next year," he said.
Next year, farmers will be encouraged to allow the edge of their fields to go unsprayed in order to allow some of the beetles to provide a food source for the wasps. They can contact Bohle at 447-6228 for more information.
"We have to allow the ce-real leaf beetle to get to a significant level to give the wasps something to eat," Bohle said. "If all goes really well, within a few years, Jefferson County grain growers will no longer need to worry about applying insecticides to their wheat fields."
Jeff McDonald can be reached at 383-0323 or at jmcdonald@bendbulletin.com.
ARTICLE ACCESS: This article is among those available to all readers. Many more articles are available only to E-Edition members. Sign up today!
blog comments powered by Disqus
