Sean McNamara used to volunteer as Redding’s tree warden — marking a few trees each year that needed to come down.
Then the emerald ash borer hit in 2012 and the workload exploded. Last year, McNamara — the owner of Redding Nursery — surrendered his duties to the town road crew.
“It got to be dozens of trees — mostly ash,” McNamara said.
So it is, throughout the state. There are millions of ash trees in the state’s forest. Very few will survive the killing plague brought on by the arrival of a bright green beetle that infests an ash and destroys its ability to feed itself.
“It’s a scourge,” said David Gardener, Roxbury’s tree warden. “It’s tragic.”
You can now see ash trees blotched with huge pale yellow patches. Those patches are where woodpeckers have torn away the tree’s bark to feed on the ash borer larvae living beneath it — a process called blonding.
“Once you see that, you know the tree is gone,” said Rick King, an arborist at the Kent Greenhouse.
The loss of ashes is the third great destructive wave to spread through the forest of the eastern United States in little over a century.
In 1904, the chestnut blight arrived in North America from Asia. The fungal disease started killing one of the great trees in the woods, largely wiping them out by the 1940s.
In 1928, the Dutch elm disease — from Asia as well, despite its name — arrived. By the 1960s the state’s beautiful urban landscape, shaded by arching elms, was gone.
“Ironically, what used to be elms were replaced by the ash,” Claire Rutledge, an assistant agricultural scientist at the entomology department of the Connecticut Agricultural Experiment Station in New Haven, said of the choices made in city landscaping.
It’s unclear whether the ash will return to Connecticut in full, or like the chestnut and elm, hang on as a sort of invalid, stunted species.
But because of increased global travel and commerce, there is an urgent awareness that the government, and private industry — growers, importers, shippers, inspectors, buyers — must increase their vigilance, lest a fourth forest plague arrive.
Experts say these pests cost the U.S. economy $5 billion a year. But Gary Lovett, a forest ecologist at the Cary Institute of Ecosystem Studies in Millbrook, N.Y., said the loss shouldn’t just be measured by economic measures. It should also be measured by the loss in biodiversity. Ash trees are part of our world.
“It’s a huge ecological loss,” he said. “I don’t think people realize that.”
Ash tree seeds feed wildlife — tadpoles eat its seeds as well as birds and squirrels. Its dark reddish-purple fall foliage added to the state’s autumn colors.
Its straight-grained wood can be used for everything from tool handles to baseball bats, to cabinets and guitars — on the album cover of “Born to Run,” Bruce Springsteen’s Fender Telecaster is made out of ash.
The emerald ash borer probably arrived nestled in a wooden packing crate, carried by a ship docking in Detroit. By the time entomologists identified it in 2002 in Michigan, it had already begun to ravage its way across the United States.
Lovett said wood is excellent material for making packing crates and pallets. It’s supposed to be treated to keep insects away, but that’s often not the case because it costs more to use treated wood.
Lovett said federal agencies, such as the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service, need to increase their inspections. The companies that pack plants, the companies that import them and the companies doing the shipping all bear some responsibility in this chain.
So do home gardeners.
“We just don’t need to import woody plants like we have,” Lovett said.
Here is the best case scenario for the ash in Connecticut.
A year after the emerald ash borer arrived in Connecticut in 2012, the experiment station began releasing parasitic wasps that kill the borer.
Rutledge said that eventually, the emerald ash borer will run out of mature trees to infest and its numbers will plummet. When ash seedlings, or young trees growing from ash stumps start emerging, she said, the parasitic wasps can keep the borer in check. Decades hence, the ash will revive.
Others aren’t so sanguine. Once a tree species is lost, it’s hard for to return as it once was.
“It was the chestnut. Then the elm,” said Gardener, Roxbury’s tree warden. “Now the ash.”