Published: June 19, 2009 12:36 am      

ENVIRONMENT: Asian species of ash borer found in area.

An invasive green species has arrived in Western New York, and state officials are taking up arms to eradicate the creatures.

Although it doesn’t pose a threat to humans, the Emerald Ash Borer, a type of beetle native to Asia, has the potential to wipe out the ash tree population. On a grander scale than what Dutch elm disease did to urban landscapes in the 1960s and 1970s.

It would also, state officials say, have an impact on the state and national economies. The eastern United States produces nearly 114 million board-feet (1-foot wide, 1-foot long and 1-inch thick) of ash timber at a value of $25.1 million. When you factor in other businesses that benefit from ash wood, the economic losses nationwide could be more than $20 billion.

Officials say it was only a matter of time before the insect arrived in New York state.

“It is not surprising,” said State Agriculture Commissioner Patrick Hooker. “This beetle has been detected on either side of Lake Ontario for several years now and there is little that can be done to stop the natural spread of this devastating pest.”

Since its 2002 detection.

in the United States, the beetle has migrated from where it was first found — the Detroit area — to 13 states and at least two Canadian provinces.

Awkward in flight, the Emerald Ash Borer mostly migrates by “artificial” means, such as movement of infested firewood, logs and nursery stock.

In an effort to halt or at least slow down its spread, the New York state Department of Environmental Conservation last year banned transporting firewood more than 50 miles. That ban is not expected to be lifted any time soon.

“We’re hopeful to stop the spread of firewood,” said Wayne Cooper, a regional forester for the DEC. “People should burn it at home, and don’t bring it into state parks.”

The first appearance of the beetle in New York state was confirmed this week, in the Cattaraugus County Town of Randolph, where between 20-30 trees have been affected.

What it is and does

Approximately 1/2-inch in length, with shiny green wings and a copper-colored underside, the adult Emerald Ash Borer can be found munching on the leaves of ash trees.

The beetle itself doesn’t do much damage to the trees. The danger lies with the larva. After a beetle lays its eggs on the tree’s bark, the larvae burrow underneath, creating tunnels called “galleries.” Moving in serpentine fashion, the larvae galleries go beyond the cambium layer, which controls growth, into the phloem, disrupting water and nutrient transport.

“The outside of the tree looks fine,” said Cooper, “but inside it is getting strangled.”

Back on the surface, the adult beetle leaves behind a D-shaped hole that is difficult to notice at first.

Signs that a tree is infected by the beetle include the canopy dying off; a yellowing, extensive sprouting from the roots and trunk; and browning of leaves. Infested trees may also exhibit woodpecker damage.

“Woodpeckers are better at finding these insects than we are,” Cooper said.

Cooper also stressed that ash trees in New York state are suffering from several maladies, so just because a tree looks sickly it may not be infected by the beetle.

The effects

With its specific taste for ash trees, the emerald ash borer could wipe out the species similar to how Dutch elm disease decimated eastern North American elm trees, mostly from the 1950s to 1970s.

Robert W. Silsby, in his book “Settlement to Suburb: A History of the Town of Tonawanda,” described the effect of Dutch elm disease: “It began its attack on the stately elm trees that lined many of the area highways during the early 1950s. In spite of public and private efforts to cut and burn diseased trees, it continued through the decade apparently little deterred by the efforts of arborists and other experts.”

Many cities and towns planted ash trees in the wake of Dutch elm disease. Ash trees “are a significant species in New York state,” said Megan Gollwitzer, a spokesperson for the DEC’s Buffalo office.

Losing the ash trees would be more noticeable than Dutch elm’s effects; there are 900 million ash trees in New York state alone, representing 7 percent of all trees in the state. There are more than a billion in Ohio. Dutch elm disease claimed a total of 200 million elm trees nationwide.

Most of the ash trees in New York state are of the white and green variety. People are likely familiar with white ash, especially if they play baseball; most wooden bats are made from the tree.

What’s being done

While driving along local roads, one may notice triangular prisms in nearby trees. Hanging from ash tree branches, their purple color starkly contrasts the surrounding green limbs. Coated with a sticky substance, the devices are baiting traps that are hoped will lure Emerald Ash Borers for collection.

Roughly 6,000 of these traps — 2,000 in Western New York — are being installed throughout New York counties adjacent to neighboring states and provinces where the bug has been detected. Spaced about 1.5 miles apart in grid-like fashion, the prisms will help determine the beetle’s whereabouts.

A mixture of manuka and phoebe oil, derived from plants native to New Zealand, is smeared on the prisms to lure the beetle, which is also attracted to the color purple.

The prisms will remain hanging for up to 90 days, when they are collected. Inspections and sample collections will occur after 45 days. People are advised to leave the prisms where they are and further warned that the sticky substance is difficult to wash off.

“We’re pretty confident we’ll determine the extent of infestation,” Cooper said.

The 50-mile limit on transporting firewood remains in place, and people are being told not to being firewood into state parks, specifically Allegany State Park.

Officials believe the primary way the insect spreads is when firewood and wood products are moved from one place to another. New York’s forests and parks are considered high-risk areas, especially Allegany due to its proximity to Randolph. Hence, the ban.

“We’re working on regulations that might lead to quarantines,” Cooper added.

A five-mile radius “delimiting survey” will take place in the Randolph area that includes an increase in trapping.

The affected trees were discovered by a pair of forest researchers who had noticed a decline in the trees. They found adult beetles, and Rick Hoebeke, entomologist at Cornell University, backed their suspicions. Samples of the bugs were confirmed by a U.S. Dept. of Agriculture laboratory in Washington, D.C.