The emerald ash borer is back, and Iowa State is ready.
In response to a statewide quarantine set by the Iowa Department of Agriculture, Iowa State has removed 300 ash trees from campus over the past seven years.
“We want to reduce the number of ash trees [on campus] from around 20 percent to 8 percent,” said Rhonda Martin, landscape architect in facilities planning and management. “There were about 1200 ash trees to begin with … when we get to 600 or 700, we’ll decide what to do next.”
Ash is used in a number of products, including firewood, paper, baseball bats and basket weaving. It is also a common shade tree in urban areas. The ash trees removed from campus are now being used by the Alumni Association to make mantle clocks and keepsake boxes, which will go on sale on their website later in the year. No ash trees that were removed from campus were infected with emerald ash borers.
The ash trees are being replaced with a “diverse number of trees including yellowwood, Kentucky coffee trees, American elms, tulip trees and catalpa,” according to Martin.
The infestation in Iowa started about three years ago. The quarantine on the movement of ash wood went into effect Feb. 11. Iowa State has been preparing for a possible infestation for the last seven years as part of a readiness plan put together by the Iowa Department of Agriculture, the Iowa Department of Natural Resources and the Iowa State University Outreach and Extension when emerald ash borers first became a threat.
The emerald ash borer is an exotic beetle from Asia that is generally half an inch long or smaller. They feed solely on ash trees, which are one of the most abundant tree species in America. The emerald ash borer is difficult to detect and impossible to eradicate since it has no natural predators in the United States and no pesticides have been developed to combat it.
Symptoms of an emerald ash borer infestation include bark splits and cracks, canopy thinning and epicormic sprouting, according to IowaTreePests.com, a website set up by the Iowa Department of Agriculture to educate the public on various pests and to provide resources for combatting them.
“No emerald ash borers have been found within 15 miles of campus,” Martin said. “But when they come, we’ll decide what to do next, whether we want to remove [the remaining ash trees] or treat them.”
Six counties in Iowa have confirmed infestations of emerald ash borers: Allamakee, Black Hawk, Cedar, Des Moines, Jefferson and Union. The quarantine that has been put into place forbids the movement of ash trees and products in and out of affected counties to prevent the spread of emerald ash borers.
To diagnose if a tree has been infested, samples can be submitted to the Plant and Insect Diagnostic Clinic at 327 Bessey Hall.