Editorial: A new enemy of the state
The wood of the white ash is light, white, straight-grained, strong and supple. Most of the greats – Mickey Mantle, Ted Williams, Carl Yastrzemski and Carlton Fisk, to name a few – swung bats made from ash, a tree whose existence in America is imperiled by an alien invader, the emerald ash borer. A tree heavily infested with the white larvae of the emerald-green beetles was discovered this month on Hall Street in Concord’s South End. Woodpeckers, which turned out in unusual numbers to feast on the larvae, sounded the alarm.
All ash nursery stock, lumber and wood chips, and all hardwood firewood, not just ash, in Merrimack County has been quarantined and cannot be taken out of the county without a permit. We urge everyone, and especially the many households that pick up a few bucks by selling campfire wood, to respect the ban and be on the lookout for the beetles. Anyone who sees the half-inch-long emerald green beetle on or near an ash tree should capture it, store it in a Tupperware container or photograph it, and report the sighting to nhbugs.org, a website operated by the UNH Cooperative Extension Service (800-444-8978).
Like many invasive species, the emerald ash borer is presumed to be a stowaway that made it to America in wood used to make shipping pallets. It is native to China and other Asian nations. The ash borer’s presence in great numbers was first noted a decade ago in Michigan and Ontario. The insect has since spread to at least a dozen states and killed an estimated 50 million ash trees.
Photographs of the beetles, and native species that are sometimes mistaken for them, can be found on the nhbugs.org site. The ash tree’s distinctive bark makes it an easy species to identify without leaves. The nhbugs site contains photographs of ash trees in every season, as well as what to watch for when looking for the borers.
The beetles bore beneath the bark to lay eggs that become larvae that eat elaborate tunnels in the ash trees’ phloem and sapwood. Eventually that blocks the flow of water and nutrients up to the top of the tree, causing its upper branches to die, often within a single year. Aerial sprays are not effective against emerald ash borers.
There’s nothing that can be done economically to protect the 25 million ash trees in the state’s forests. The state Department of Agriculture plans to issue recommendations for homeowners with ash trees who want to protect them from invasion or combat an infestation caught in its early phases. Once the beetles have a good hold on a tree, however, it can rarely be saved and instead must be felled and destroyed.
Several products approved for use by homeowners can be purchased locally. Others must be applied by an arborist licensed to apply pesticides. Common treatments include a systemic insecticide that’s poured into a shallow trench in the soil where it can be taken up by the tree’s roots. Success is not guaranteed, but when it works, protection can last a year or two and spare the homeowner the loss of a valuable shade tree and the expense of having it taken down.
The ease of global travel, now combined with a warming climate that allows fire ants and other species from warmer climates to expand their range ever northward, has created a constant need to battle invasive species. The emerald ash borer now joins a very long list of enemies of the state.