Several tree-killing insects spotted locally

YATES, SCHUYLER COUNTIES—There are a number of insects that threaten trees and a deadly one, the Hemlock Wooly Adelgid, has been spotted here in August.

Jerry Carlson, a research scientist with the Department of Environmental Conservation’s Division of Lands and Forests, held an informational meeting about the pest last Thursday. When gone unchecked, it has devasted forests in the Smoky Mountains of Tenessee and North Carolina.  However, Carlson said and hopes the cold here may prevent the adelgid, originally from Japan and coastal China, from being a threat.

“The HWA is here, it’s not going away,” said Carlson.

It is still to early to tell as it takes a few years for the invasive insect to kill trees.  The Hemlock Wooly Adelgid was found in August in Yates and Schuyler Counties.  The infected trees are located along Seneca Lake where the two counties share a border, in the crook of Keuke Lake and halfway up Seneca Lake on both sides.

“(New York’s hard wood forests) are statistically the most valuable in the world,” said Carlson.

He explained how they feed on the trees.  Upon hatching from their eggs, the “crawlers” attach themselves to hemlocks where the needles grow out of the branches.  The insects are incredibly small, looking like flecks of pepper.  As they mature they actually connect to the tree on a cellular level and suck the nutrients from the tree.

The adult adelgids then lay their eggs, covering them with a wooly cover.  This is when they are easiest to spot.  The adults usually lay eggs in March/April and the second generation does the same in June.  Those eggs hatch in the following month and the insects usually mature into adults and stay dormant through the winter.

“With the warm fall I suspect they are getting ready to lay eggs,” said Carlson.

He explained that it takes more than one generation to really kill the trees.  When the tree comes close to dying, the adelgid loose their food source and mostly die off.  The hemlocks revive, but may not be able to survive another onslaught that bad again.

“There is I think, good news,” said Carlson.  “There is more awareness every year.”

The Hemlock Wooly Adelgids were first discovered in the U.S. in 1924, though no one knew they would be a threat.  They made their way to eastern states in the 1950s.  Carlson said they do not know exactly how they end of being transported, but do credit birds, wind and the transport of fire wood.

In 1985 the first adelgid was found in New York in Westchester County.  The southern most part of the state and Long Island have the worst infestation of the pest.  There are currently over 20 counties in New  York with confirmed Hemlock Wooly Adelgid.

“There are Girl Scouts, Boy Scouts, school organizations looking and wanting to learn,” said Carlson.

Vigilance is the best weapon against this, and other invasive threats.  Carlson said they know what to look for, but it is more likely that someone else will find the pest before the DEC or CCE does.

Carlson talked about two pesticides which look like they work.  They are Imidacloprid and Dinotefuran.  Both can be injected right into the tree so the adelgid absorb it and die.  He explained that while it has proven to be effective, there has been a five plus years later when the adelgid reappeared.

Brett Chedzoy also presented quickly about three other threats to trees; Oak Wilt, the Asian Longhorn Beetle and the Emerald Ash Borer.

If anyone thinks they have the Hemlock Wooly Adelgid, or any such threat to trees, they are invited to take a photo of the pest/problem and send it to that county’s Cornell Cooperative Extension.  The number for Schuyler County’s CCE is 607-535-7167 and Yates County’s is 315-536-5123.  Carlson’s e-mail is jacarlso@gw.dec.state.ny.us.