Killer invading ash trees

Jun. 22, 2013 @ 04:17 PM

The emerald ash borer has been spotted in Vance, Granville and Person counties.

This little insect is a killer. The adult is metallic green and about one-half inch long. The larvae are white, flat-headed with distinct segments.

The adults emerge in late spring and the female lays eggs shortly after emerging.

When the larvae hatch, they bore into an ash tree and feed under the bark, cutting off circulation of water and nutrients. If not stopped, the tree eventually will die.

The emerald ash borer, a native of Asia, was first found in the United States in Michigan in 2002. Since then it has spread to 20 states.

Lance Walheim, a horticulturist with Bayer Advanced, a company providing products for lawn and tree care, said, “We’ve been watching it closely. It’s devastating and it’s moving.”

The discoveries in the Tri-County were made this month.

Walheim said there are several signs that indicate a tree is infected:

• The tree starts thinning out at the top.

• The bark is splitting.

• Tracks under the bark show where larvae have fed.

• Woodpeckers are actively feeding on the larvae.

If these signs are noticed, the tree can be treated with products to stop the emerald ash borer.

“The product is poured at the base of the tree,” he said. “It’s absorbed up into the tree.”

The treatment should be applied once a year, in the spring or fall.

Paul McKenzie, horticulture agent with the Vance County Cooperative Extension Service, said, “Ash trees are not common in this area. There are not many large stands.”

That’s a plus. Individual trees are easier to treat than large stands.

The emerald ash borer can spread short distances by flying from one tree to another. However, the biggest threat across long distances occurs when beetles or larvae are accidentally transported from an infested area to another area. This is usually done by humans shipping infested ash wood to another location.

It is for that reason that Granville and Person counties have been placed under a quarantine by the N.C. Department of Agriculture and Consumer Services. Under the quarantine, no ash trees can be moved outside the quarantined area.

In addition, no cut hardwood firewood of any kind can be moved out of the quarantined area.

If an individual or organization wants to move ash trees or ash firewood out of the quarantined area, they must reach a compliance agreement with the department in order to obtain a certificate.

Individuals wanting more information about the emerald ash borer can contact the following sources:

• McKenzie at (252) 438-8188.

• Vance County Ranger Brad Manring at (252) 438-7249.

In addition, the North Carolina Forestry Service website has a link to Frequently Asked Questions related to the emerald ash borer. It can be accessed at ncforestservice.gov.

Individuals can report an emerald ash borer infestation by calling the pest hotline at (800) 206-9333 or by email at newpest@ncagr.gov.

 

Contact the writer at dirvine@hendersondispatch.com.