Cornell University and the Finger Lakes Land Trust have partnered together to combat a pest that that threatens to kill eastern hemlocks found in many of the forests and gorges in the region.
The land trust and university will combat the hemlock woolly adelgid, an invasive insect from Japan, as part of the New York State Hemlock Initiative. The initiative integrates statewide research, management and outreach to conserve New York’s hemlocks.
The hemlock woolly adelgid reached the Finger Lakes region in 2008. In response, the land trust and NYSHI created a partnership to establish biocontrol populations — of Laricobius beetles and Leucopis silver flies — on several nature preserves.
In 2018, NYSHI released silver flies on hemlock trees at the land trust’s Ellis Hollow and Lindsay-Parsons Biodiversity preserves.
The flies are released into fine mesh bags and placed on one localized hemlock branch where they will lay their eggs. When the fly eggs hatch, the larvae will eat hemlock woolly adelgid eggs, thus reducing the population of hatching hemlock wooly adelgid in the late spring and early summer.