‘Biblical’ insect swarms prompt Oregon to fight pests
Driving on a windy canyon road through the pastures of northern Oregon, Jordan Maley and April Aamodt are on the lookout for Mormon crickets, giant insects that can ravage crops.
“There’s one right there,” Aamodt said.
They are not difficult to spot. The insects, which can grow to over 2 inches (5 centimeters), stain the asphalt.
Mormon crickets are not new to Oregon. Originating in western North America, their name dates back to the 1800s, when they ruined the fields of Mormon settlers in Utah. But amid drought and warming temperatures – conditions favored by insects – outbreaks across the West have worsened.
The Oregon Legislature last year allocated $5 million to assess the problem and implement a program to “suppress” Mormon cricket and grasshoppers. An additional $1.2 million for the program was approved earlier this month.
It’s part of a broader effort by state and federal authorities across the western United States to deal with an outburst of Mormon grasshoppers and crickets that has hit from Montana to Nevada. But some environmental groups oppose the programs, which rely on the aerial spraying of pesticides over large areas of land.
Maley, an Oregon State University extension worker, and Aamodt, a resident of the small town of Arlington on the Columbia River, are both involved in efforts to raise awareness and investigate the Mormon cricket in the area.
In 2017, Arlington experienced its biggest outbreak of Mormon cricket since the 1940s. The roads were “greasy” with the crushed innards of the huge insects, which damaged nearby wheat crops.
Breeder Skye Krebs said the outbreaks were “truly biblical”.
“On the highways, once you kill them, the others come,” he explained. Mormon crickets are cannibalistic and will feast on each other, dead or alive, if they are not sated with protein.
The insects, which are not true crickets but shield-backed grasshoppers, are flightless. But they can cover at least a quarter mile in a day, according to Maley.
Aamodt fought the 2017 outbreak with what she had on hand.
“I got the lawnmower out and started mowing them and killing them,” she said. “I took a straight hoe and stabbed them.”
Aamodt organized volunteers to fight the infestation and earned the nickname “Queen of Cricket”.
Last year, another infestation caused local authorities to “joke each other”, Maley said.
“We had all these high-value crops and irrigation circles,” he explained. “We just had to do what we could to keep them out of this.”
In 2021 alone, agricultural officials in Oregon estimate that 10 million acres of rangeland in 18 counties were damaged by Mormon grasshoppers and crickets.
Under Oregon’s new initiative, private landowners such as farmers and ranchers can ask the Oregon Department of Agriculture (ODA) to investigate their land. If the ODA finds more than three Mormon crickets or eight grasshoppers per square yard, it will recommend chemical treatment. In some areas near Arlington surveyed in May shortly after hatching, there were 201 Mormon crickets per square yard.
State officials recommend aerial application of diflubenzuron. The insecticide works by inhibiting development, preventing nymphs from becoming adults. Property owners can be reimbursed up to 75% of the cost.
Diana Fillmore is a breeder participating in the new cost-sharing initiative. She says “the ground is crawling with grasshoppers” on her property.
The ODA recommended that he treat his 988-acre ranch in Arock, southeast Oregon. Since the program’s protocol calls for applying insecticide to only half of the proposed area, alternately targeting swaths and then skipping the next one, that means nearly 500 acres of his land will actually be sprayed.
Fillmore decided to act, remembering the damage of the last year.
“It was awful,” Fillmore said. “The locusts have completely wiped out some of our fields.” She was forced to spend $45,000 on hay that she wouldn’t normally have to buy.
Todd Adams, entomologist and coordinator of the ODA’s Eastern Oregon Field Office and Grasshopper Program, said that by mid-June the ODA had received 122 survey requests and sent 31 treatment recommendations for approximately 40,000 acres (16,187 hectares).
Landowners should act quickly if they decide to spray diflubenzuron as it is only effective against nymphs.
“Once they become adults, it’s too late,” Adams said.
Oregon’s new program is for private landowners. But the federal government owns more than half of Oregon’s total land, and the US Department of Agriculture has its own program for outbreaks on western public lands.
The U.S. government’s grasshopper suppression program dates back to the 1930s, and the USDA’s Animal and Plant Health Inspection Service (APHIS) has sprayed millions of acres of pesticides to control outbreaks since the 1980s. .
APHIS national policy director William Wesela said the agency sprayed 807,000 acres (326,581 hectares) of rangeland in seven western states in 2021. So far this year, it has received treatment demands in Oregon, Idaho, Montana, Utah, Nevada and Arizona, according to Jake Bodart, its director of plant health for Oregon.
In a 2019 risk assessment, APHIS acknowledged that the primary insecticide used, diflubenzuron, remains “a restricted use pesticide due to its toxicity to aquatic invertebrates,” but said the risks were low.
APHIS says it follows methods to reduce worry. It instructs pesticide applicators to skip windrows and apply the insecticide at lower rates than stated on the label.
But environmental groups oppose the program. Last month, the Xerces Society for Invertebrate Conservation and the Center for Biological Diversity (CBD) sued APHIS in US District Court in Portland. In their filing, they accuse APHIS of harming rangeland ecosystems and failing to adequately inform the public about treatment areas.
They also allege that the agency violated the National Environmental Policy Act by failing to evaluate all alternatives to pesticides or analyze the cumulative effects of the program.
Federal officials declined to comment on the lawsuit because it is pending in court.
Conservationists say the reduction in grasshoppers decreases the food source for other wildlife that feed on them.
“We are very concerned about the impact of these broad, sweeping sprays on our grassland and rangeland ecosystems,” said Sharon Selvaggio, Xerces Society’s pesticide program specialist.
Selvaggio added that the sprays can be “toxic to a wide variety of insects” beyond grasshoppers and Mormon crickets, expressing particular concern for pollinators such as bees.
Both environmental groups want the agency to take a more holistic approach to pest control, exploring methods such as rotational grazing.
“We’re not trying to stop APHIS from using pesticides again,” said Andrew Missel, an attorney at Advocates for the West, the nonprofit law firm that filed the lawsuit. “It’s really about reforming” the program, he added.
In Arlington, “cricket queen” Aamodt said residents have been experimenting with alternatives to pesticides. In 2017, some trees covered with duct tape to trap insects. The following year, the local authorities brought goats to graze the hillsides.
For now, those battling future infestations are hoping the state’s new program will provide much-needed support.
“Keep in mind these are people who are taking time out of their own lives to do this,” said OSU extension worker Maley. “The volunteers made a huge difference.
Rush is a member of the Associated Press/Report for America Statehouse News Initiative. Report for America is a nonprofit national service program that places reporters in local newsrooms to report on underreported issues.