Posted: Thursday, March 22, 2012 11:00 AM
State inspectors survey 80 nurseries for fungal disease
By MITCH LIES
State plant officials found boxwood blight in two nurseries last month, bringing to three the number of Oregon nurseries found with infected plants.
All three nurseries are in Washington County, according to Dan Hilburn, administrator of the Oregon Department of Agriculture's plant division.
The discoveries came as part of surveys requested by the nurseries, Hilburn said.
The most recent discoveries came in early and mid-February and contained smaller patches of the fungal disease than the initial December discovery, Hilburn said.
In all three cases, the nurseries buried or burned infected plants and boxwoods within a 2-meter radius of the infected plants under orders from ODA, Hilburn said.
"The idea is to get it out of the nursery trade," Hilburn said. "That is our goal here, so people can buy our boxwoods and not have to worry about them being infected."
ODA inspectors have surveyed 80 nurseries since the first discovery, Hilburn said.
Officials do not believe the three discoveries are connected. They are unsure how the disease made its way to Oregon.
"There is not a pattern that would cause you to suspect that it came in at one time from one source," Hilburn said.
Boxwood blight has been found in nine states and one Canadian province. It has been present in New Zealand and Europe for about a decade.
In severe cases, boxwood blight can defoliate boxwoods. Infected plants also exhibit discolored stem cankers and a white powdery appearance on leaves and stems.
The disease strikes quickly, Hilburn said.
He advised nurseries when buying boxwoods to segregate shipments and monitor the plants for a month or so before incorporating them into their regular stock.
"You just don't move it into your other plants right away," Hilburn said. "That's how it can spread."