High up in the canopies of some of the largest trees in Nova Scotia, a tiny black insect, barely the size of a sugar crystal, is causing significant damage. The hemlock woolly adelgid, an invasive species detected in the province in 2017, is swiftly spreading through Nova Scotia’s hemlock forests, resulting in the eerie sight of ghostly trees in its wake. By extracting sap from the base of hemlock needles, this insect can fatally harm a tree within less than a decade, leaving behind a white wool-like residue, which gives it its name.
At Acadia University’s campus, a team of scientists is actively researching to find a solution to combat this menace. Led by Acadia, a research initiative is underway to study the impact of insecticidal treatments utilized to manage the hemlock woolly adelgid. Additionally, they are setting up a biological control facility to regulate adelgid populations.
Kirk Hillier, a biology professor at the university and the lead researcher, emphasized the urgency of the situation due to the visible threat posed by the dead hemlocks, known as the “grey ghosts.” The research project aims to evaluate the consequences of adelgid infestation on biodiversity and the efficacy of insecticides, which are crucial for preserving the hemlocks.
Hemlocks are currently treated with two forms of insecticide, either by injection or bark spraying. Despite the laborious efforts of volunteers and government agencies, only around 600 hectares of hemlocks in Nova Scotia have undergone chemical treatment. To optimize treatment allocation, the project is testing specialized traps equipped with molecular tools to detect adelgid at early stages.
The long-term strategy involves utilizing traps to identify hemlock predators, particularly Laricobius nigrinus, a small black beetle crucial for combating the hemlock woolly adelgid. Establishing a biocontrol facility at Acadia is pivotal for rearing these predators and potentially introducing other species like the silver fly to manage the invasive insect naturally.
The project’s multi-faceted approach, encompassing short-term chemical control and long-term biological solutions, is vital for safeguarding Nova Scotia’s hemlocks. Public awareness and sustained governmental support are crucial for the success of these conservation efforts, ensuring the preservation of the province’s iconic hemlock trees for generations to come.
