Hemlocks in Peril...
Tall dark eastern hemlock stands were a defining feature of the forests in Mi’kma’ki for thousands of years. Though old forests are increasingly rare in Nova Scotia, the hemlock is still an important component of mixed Wabanaki-Acadian woods. With individuals living more than 400 years, hemlocks demonstrate their rugged capacity to withstand the tests of time. Sadly, trees are dying rapidly in Nova Scotia due to a tiny invasive insect, the hemlock woolly adelgid (HWA). The health of the eastern hemlock is tightly connected to the health of both aquatic and the broader forest ecosystem. Streams flowing under shady hemlock stands are cooled and buffered from erosion and flooding that would muddy their waters, fostering a more suitable and stable habitat for species like salmon and trout.
Our Strategy
Existing efforts to protect hemlock from the woolly adelgid have largely focused on reducing the transportation of firewood, improving monitoring efforts, and promoting public awareness. Actions like these are important but they are falling short. Treatment of individual hemlocks with a specialized insecticide is a proven long-term strategy benefiting from decades of research in the States and is begining to be implemented in Nova Scotia. Small amounts of these pesticides are injected directly into the tree’s lower trunk where the chemical reaches the sap and is transported to tissues under attack in the canopy.
A single chemical treatment allows the tree to live for 4-7 years before requiring retreatment. This buys vital time for implementation of a biocontrol program, where HWA predators are introduced and allowed to build sufficient numbers in the environment to effectively control the invader without further need of pesticides. This stopgap intervention may also allow time for natural adaptation to take place.
The province has embraced chemical treatments on public lands through a new program targeting hemlocks in Protected Areas, supported by funding from a federal Department of Environment and Climate Change fund. Treatments are very expensive though and, the majority of Nova Scotia being private lands, many hemlock stands are left vulnerable to HWA. Nature Nova Scotia is stepping in to help fill this gap, treating trees on private lands and prioritizing stands with high ecosystem function values.
In the Spring of 2023, we launched the Hemlock Conservation Legacy Fund to support this work.
Fund Objective: Fund chemical treatments for hemlock trees under threat of mortality from the invasive hemlock woolly adelgid (HWA) across Nova Scotia. Funds would treat high-value hemlocks and/or riparian hemlocks that would otherwise be left untreated and die, on private lands.
Timeline: Fundraising Summer 2023 – 2024, Treatments Seasonally starting in Fall 2023
Donors are invited to follow our donation structure below or donate as they can:
“Individual” or “Honour A Loved One” donors – Save a single hemlock tree
$ 50.00
“Salmon and Trout” donors – Conserve hemlocks lining salmon or trout pools or streams
$ 500.00
“Old Growth” donors – Protect an entire old growth hemlock forest glen
$ 1000.00
All other donations welcome and appreciated.
From the Field: 2024 Treatments
Here are some photos from recent treatment events, where volunteers helped inject hemlocks in Kespukwitk/South-West Nova Scotia.
