UTAH (ABC4) – An invasive insect species is threatening to kill aspen trees native to Utah.
Researchers from Utah State University have confirmed the presence of the insects in Utah forests. The insect, called oystershell scale, is a tiny, sap-sucking creature that looks like an oyster or mussel. It attaches itself to the bark of a tree. They will initially affect a small portion of the tree, but will eventually take over full branches, effectively killing the host.
They tend to hang out in shady parts of a tree and prefer avoiding direct sunlight. Their presence was most recently discovered in the Uinta-Wasatch-Cache National Forest in Pole Canyon, located east of the Provo area.
Officials say young trees are particularly susceptible to the insect, which has caused worry as many Utah forests already lack young aspen trees. The most affected species are ash, aspen, willow, cottonwood, and boxelder trees in Utah.
“Quaking aspen is the most widely distributed tree species in North America, and it adds an important component of biodiversity, wildlife habitat, and fall color to Utah landscapes,” said Darren McAvoy, Utah State University Extension assistant professor of forestry.
So far, park experts are doing what they can to stop the invasion in its tracks.
“Applying fire to the affected landscape appears to be the most promising management strategy for controlling the spread of oystershell scale, but we are just starting to learn about it, so more research is needed to understand this relationship,” says McAvoy. “Historically, other invasive species have practically wiped out certain species of trees in the U.S., including the American chestnut and western white pine. Oystershell scale is known to have killed large groups of native forest tree species in several eastern states. It is currently causing significant damage to aspens in northern Arizona, where it has been active over the past decade, weakening and killing aspen trees below 8,200 feet in elevation.”
What can the public do to help?
Officials say it’s important not to move firewood that may be infected by oystershell scale into a forest. If the invasive insects are spotted in the wild, confirmed sightings along with a GPS location, photo and a description of the affected tree, should be sent via email to park official Justin Williams of the USDA Forest Service at firstname.lastname@example.org.