BURRILLVILLE – With exotic beetles that have the potential to destroy all of the area’s ash trees discovered in four Rhode Island counties, local conservationists and those who study the bugs have taken action.
The Burrillville Land Trust and experts with the University of Rhode Island Biocontrol Lab recently released 209 parasitoid wasps at the Edward Vock Conservation Area in Pascoag in hopes to protect the trees from extinction.
“With the release of these parasitoid wasps, all hope that we save our native ash trees,” said BLT President Paul Roselli.
Roselli took part in the release of the wasps, adult Spathius galinae – which are a parasitoid of the invasive beetle known as the emerald ash borer. The wasps attack the larvae of beetle, and kills them before the can mature.
The beetle reportedly arrived accidentally in the early 1990s in cargo imported from Asia.
The Burrillville conservation area on Jackson Schoolhouse Road has been the sight for much of the research and release of these parasitoid wasps in northwestern Rhode Island. The two other species of parasitoids that were released in past years at the Vock Conservation Area were Tetrastichus planipennisi – another larval parasitoid, released from the small ash bolts hung from the trees – and Oobius agrili – an egg parasitoid, released from the small medicine bottle-looking implements that also hang from trees.
Emerald Ash Borer have been found in four of the five counties in the state, with none of the beetles detected as of yet in Bristol County.
Alana Russell from the URI Biocontrol Lab; URI graduate Saffron Zaniewski, who also works at the lab; and Paul Ricard from URI will be conducting detection trapping in Bristol this year.
One of the first properties where the beetles were detected in 2018 was a second lot owned by the land trust on South Shore Road. The EAB was discovered using a purple prism trap, devices visitors to the area may have noticed high above in the tree canopy. Ricard went back in 2019, girdled trees and collected larvae.
“So far, the trees at the Vock conservation area are still in good condition, given that the first state detections were not far away near Wallum Lake,” Roselli said.
Other sites of interest along Round Top Pond are showing signs of decline due to the EAB infestation, he noted.
“We are hopeful that these little creatures will help save these majestic ash trees from extinction,” said Roselli.
For more information, a forest service brochure on EAB biocontrol and ash regeneration can be found here. Those interested in saving their own trees from the Emerald Ash Borer can also find an article on the beetles from Northern Woodlands here.
