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Laurel Mountain Borough learns about invasive insect

| Wednesday, July 24, 2013, 9:01 p.m.

Following the monthly council meeting of Laurel Mountain Borough, foresters from the Pennsylvania Department of Conservation and Natural Resources gave a presentation with information on Hemlock woolly adelgid. The invasive aphid-like insects are killing hemlock trees throughout the east coast and Laurel Mountain Park is experiencing this problem.

Council president Joseph Griffith Jr. said the presentation was an opportunity to inform the council and residents, though the borough does not have a set plan for dealing with the problem at the present time.

“We have to talk to the residents and with the Laurel Mountain Park Association to see what we can do and how we should approach it. I wanted to get some information so we can plan what we can do and what we should do,” Griffith stated.

Forest Health Specialist David Schmidt from the Bureau of Forestry in Ebensburg said the adelgids attach themselves to the openings on the trees where needles have fallen and suck carbohydrates and other nutrients from the tree, leaving the tree malnourished and unable to grow.

Adelgids reproduce parthenogenetically, meaning without a mate, and Schmidt said often up to three insects would attach to a single new needle of a tree. As the populations of the insects grow, the tree cannot produce the necessary food to sustain the adelgids, and they die off. Then as the tree recovers, the insects return to feed again.

“It just continues this cycle,” Schmidt explained. “The problem is the hemlock never fully recovers. So after a certain number of these cycles, the health just keeps declining until you have a drought, or some root disease that gets in there and the tree just has no energy to fight this off, and it's over.”

Fallen hemlocks, Schmidt went on, open up areas that were formerly shady, which allows invasive plants to get a foothold in the new sunny spot. Local wildlife and invertebrates do not eat these foreign plants, because it disturbs the animals' digestion, allowing the invasive plants to further propagate.

Schmidt detailed a two-part process for treating the problem. The first is a chemical called Imidacloprid, which would be injected into the soil, and absorbed by the trees, which makes them toxic to the adelgids. This chemical lasts five years and is sold in stores like Lowes under the brand name Bayer Tree and Shrub Protect and Feed.

Schmidt explained that whoever applies the chemical must be trained to ensure the safety of that person, the trees and nearby residents.

“They have to be trained in the safe and proper use of the product, how it's used, how it's mixed and the proper personal protective equipment to wear, which is critical,” Schmidt said.

The second part of the treatment is in the use of the Laricobius nigrinus beetle, which eats the adelgids. Schmidt explained that the insects are still in the testing phase, but would be used in a quarantined condition to avoid any unwanted after-effects following the adelgid eradication.

“We don't want to bring in a problem,” Schmidt commented. “Everybody thinks we brought in those ladybird beetles that get all over everything, and we didn't. They are rough on the aphids, but they are a pain. We are real careful about what is brought and what we decide we want to actually begin doing experiments with.”

Griffith said the council would talk about the information presented and decide a plan of action after discussing with local residents and other park associations.

The next meeting is 7:30. Aug. 21 at the community center of Laurel Mountain Park.

Peter Turcik is a contributing writer for Trib Total Media.