Apple Maggot Numbers May Be Declining State Officials Say Pesky Insects Not Showing Up In Most Tests
The worm may be turning for some of Washington’s apple growers.
According to the Washington state Department of Agriculture, the number of apple maggots statewide may be down.
The apple maggot fly is particularly pesky for tree fruit growers because it turns infested apples brown and mushy. It’s a great threat to the $684 million state industry.
“It’s not a real pretty picture to imagine biting in there and seeing larvae,” said Mike Klaus, an entomologist with the state Agriculture Department.
The pest affects apple, crabapple and Hawthorne trees. At one point in the 1980s it was costing commercial apple growers $70 million to eradicate the insects.
To control the spread of the flies in the 1980s, the state first enacted quarantines, prohibiting people from transporting apples from known infected areas such as Spokane and Klickitat counties and Western Washington.
The block on transporting the fruit has helped, even in Spokane, said Sydney McCrea, a Master Gardener and longtime adviser to many Spokane garden hobbyists.
“We haven’t seen it very often here,” she said. “There have been a few showing up, but not very much.”
And most of those were in the Spokane Valley, Klaus said.
On the other hand, “We’ve never caught an apple maggot up in Green Bluff,” he said, referring to Spokane County’s pocket of small family-run orchards just north of town. “We continue to test up there to show that apple maggots are not threatening these orchards.”
Likewise, tests in Yakima County didn’t turn up a single apple maggot fly last year, Klaus said.
Ellensburg is a different story. A 1998 test showed signs of apple maggots in one place and a similar test in 1999 turned up the insect just a block away, evidence that there is a colony nearby. When this happens, Kraus’ crew reports it to the county pest board, which either removes the fruit or sprays insecticide to kill the flies.
Still, inspections statewide last year didn’t turn up any infected fruit destined for commercial sale.
The apple maggot fly is slightly smaller than a house fly and its wings have dark stripes. The insect lays its eggs on developing fruit. The larvae then tunnel through the fruit, destroying both the skin and the flesh.
The state Agriculture Department will continue its statewide survey and is now distributing traps for the insect. For more information, call Mike Klaus at 509-225-2609.