Phragmites australis is among Ontario’s most problematic invasive plants, degrading wetlands and coastal habitats, and reducing biodiversity. Located on a constructed landform on Toronto’s waterfront, Tommy Thompson Park is highly vulnerable to invasive plant species. Phragmites rapidly outcompeted native vegetation across more than 8 hectares within emergent aquatic zones, sheltered embayments, and terrestrial habitats. Toronto and Region Conservation Authority initiated the Tommy Thompson Park Phragmites Management Strategy in 2018. The program was designed to follow a 5 year adaptive management framework, integrating chemical control (glyphosate), mechanical removal (mowing and spading), annual monitoring (site specific and PAMF), and targeted restoration. Management is implemented annually across all impacted areas and outcomes are strong, with overall phragmites decline by 90% (notwithstanding annual variability). Native aquatic vegetation is recovering through natural regeneration and planting. A secondary invasion of Flowering Rush is being managed in the Triangle Pond wetland coinciding with meadow marsh and upland meadow restoration. Although planned as a 5-year strategy, the inter annual fluctuations in abundance highlight the necessity of sustained monitoring and maintenance to preserve biodiversity. In 2025, a biocontrol nursery was established to introduce moth control agents as part of the management approach; monitoring results are expected in a few years.
