Aphids linked to Morrow County wheat withering
Umatilla County problems found to be unrelated; probe wraps up
By MATTHEW WEAVER
Aphids caused the withering of wheat in Morrow County, an Oregon State University scientist says.
OSU extension agronomist Larry Lutcher said 2,000 to 3,000 acres were damaged last fall in Morrow County, down from an original estimate of 30,000 to 40,000 acres.
"The problem has luckily turned out to be a fairly minor problem," he said. "It's really being overshadowed by the rust right now."
Damp, cool weather has caused an outbreak of stripe rust in many wheat-growing areas of the Northwest.
Lutcher isn't concerned about a repeat of aphid problems.
"A cereal yellow dwarf virus infection caused by aphids sometimes is very unusual in the fall," he said. "It was a situation where all the stars aligned perfectly."
Crops infected by the virus would not recover, Lutcher said.
Lutcher recommends farmers who plant before mid-September apply insecticide to the seed, providing about four weeks of protection.
In nearby Umatilla County, the Oregon Department of Agriculture expects to close 20 unrelated investigations into wheat withering last fall.
In November, growers reported instances of wheat withering on 4,000 acres.
Dale Mitchell, assistant administrator of the department's pesticides division in Salem, Ore., said staffers are drafting their findings.
The department is reviewing the cases to determine whether there is enough evidence to indicate alleged violations of the state pesticide control law through drift of chemicals to adjoining properties.
"In some of the investigative findings, we do have the presence of glyphosate detected," Mitchell said.
The evidence in each case must determine whether the glyphosate found on a location came from another location and was the responsibility of another party.
"Just the finding of glyphosate may not be enough evidence to support that a particular party was responsible," Mitchell said.
If responsibility can be determined, the department decides on an appropriate enforcement response, ranging from a notice of violation to a fine or action against a license. The situation depends on whether the individual's history of violations, Mitchell said.
Mitchell hopes to have the findings concluded by the end of June.