It all began at a commercial campground on Rt. 32 several years ago when infested firewood was brought in from out of state by an unsuspecting camper. In the ensuing years, it has spread out over most of Ulster County and made the jump across the Hudson River into Dutchess County. And while there’s no cost-effective way to save most trees from the invasive emerald ash borer, many towns (and homeowners) are choosing to inoculate prized ash trees against the scourge of their wild cousins.
“This infestation is on par with Dutch elm disease and the chestnut blight,” said arborist Vern Rist as he administered a dose of pesticide to an ash tree at Seamon Park May 22.
Saugerties-based Rist, owner of a company called Healthy Plants, was hired by the village to treat four ash trees at the verdant Rt. 9W park at a total cost of $1,020. The trees were already infested, but this should kill the ash borer larvae. Another treatment will be needed in two or three years.
The Seamon Park trees are the first the village has decided to treat. Five other village ash trees have been cut down and burned. A tree survey is planned for this year, which will determine how many ash trees the village has and which are infected.
It’s the larvae of the beetles that kills the trees, Rist explained. The beetles lay their eggs under the bark of the tree, and when in the larvae stage they devour the tender wood and destroy the tree’s circulation system.
Much like the human body, a tree has a circulation system, which brings in water and nutrients from the ground through the root system and distribute it throughout the tree. If that system is destroyed by the larvae, the tree dies.
So, to continue the human body metaphor, the arborist drills holes in the base of the tree, much like a doctor sticking a needle in the arm of a sick patient. Into each of the holes, Rist and his assistant Josh Van Loan insert a needle that leads to a tube and then into a bottle, much like an IV in a sick patient. The bottle, which contains a pesticide, is pressurized, so when applied the pressure causes the substance to flow into the tree where it is spread throughout the circulatory system, killing the larvae.