

Invasive Species
WHAT IS AN INVASIVE SPECIES?
Invasive species are non-native organisms, including plant, animal, insect and pathogen species, that are introduced outside of their native range, and are able to outcompete native species for resources and space. They often lack their natural population controls such as predators and, as a result, can reproduce and spread quickly. They are very adaptable and have the ability to transform entire ecosystems.
Invasive species are a major concern worldwide and continue to plague land and water managers at a national, provincial and local level. The threat of established or potential introduction of invasive species will continue to impact our economy and environment with international trade, climate change, habitat loss and fragmentation.
WHAT IS CLOCA DOING?
Invasive Species Management Strategy
Central Lake Ontario Conservation (CLOCA), like other Conservation Authorities across the province, has put in place an invasive species management strategy to protect watershed biodiversity, and reduce the social and economic impacts on our communities.
CLOCA's Invasive Species Management Strategy (2017-2027) is a 10-year action plan that provides direction for CLOCA's various departments. This tool will be used to promote discussion amongst our watershed management partners and assist us in securing long-term support to fulfill the objectives set out within the strategy.
The guiding principles of this document are to prevent, detect, respond and manage invasive species in our watershed. This strategy guides us as we prioritize species for management, examine and update internal policies and procedures, educate and reach out to engage stakeholders and develop communication products to address invasive species. We regularly implement the principles of our Invasive Species Management Strategy in our watershed including through our Integrated Watershed Monitoring Program.
Current Invasive Species Monitoring and Management

EMERALD ASH BORER*
EMERALD ASH BORER
Jewel beetle native to north-east Asia.
IMPACT
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99% mortality rate on ash trees
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Adult lays eggs on ash tree bark; larva feeds on the inner bark (cambium) which slowly kills the trees
CLOCA'S ACTION
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Distribution mapping
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Monitoring tree health
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Hazard tree removal
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Restoration planning
Infected trees in our Conservation Areas have been marked with yellow dots as part of our ash tree inventory.

PHRAGMITIES*
(Frag-mite-eez)
PHRAGMITIES
Phragmities australis or "phrag" is a perennial wetland grass native to Eurasia.
IMPACT
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Creates dense stands, crowding out native vegetation and degrading wildlife habitat
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Spreads by root fragments and seeds
CLOCA'S ACTION
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Herbicide and physical removal at Heber Down Conservation Area
This management has been ongoing since 2016, in partnership with Enbridge, Trans Northern Pipeline and Hydro One.
GARLIC MUSTARD*
GARLIC MUSTARD
Biennial understory plant native to Europe. Introduced as a medicinal herb.
IMPACT
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Outcompetes Ontario's native forest spring wildflowers including trilliums and trout lilies
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Unappealing to wildlife due to its strong garlic taste
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Spreads by seeds
CLOCA'S ACTION
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Physical removal at Purple Woods Conservation Area
This management has been ongoing since 2013 through CLOCA's high school education program To Beat it, We Eat it.

DOG-STRANGLING
VINE
DOG-STRANGLING VINE
DSV or pale swallow-wort is a perennial vine-like plant in the milkweed family.
IMPACT
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Creates dense stands that crowd out native plants, preventing forest regeneration and impacting biodiversity
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Uses the wind for seed dispersal
CLOCA'S ACTION
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Managed at Purple Woods, Crow's Pass and Enniskillen Conservation Areas
The location of this management is based on the prioritization of the highest quality habitat.

GIANT HOGWEED
GIANT HOGWEED
Monocarpic perennial (which means it takes many years before it flowers), but once it flowers, it dies. Native to the Caucasus region of southwest Asia. Introduced as a garden ornamental.
IMPACT
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Human health risk: sap causes severe skin burns when exposed to sunlight
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Creates monotypic (only one type of species) communities in wet areas
CLOCA'S ACTION
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Distribution mapping and reporting in partnership with Ganaraska Conservation and the Municipality of Clarington.
WILD PARSNIP*
WILD PARSNIP
Monocarpic perennial (which means it takes many years before it flowers), but once it flowers, it dies. Suspected introduction by European Settlers as an edible crop.
IMPACT
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Human health risk: sap causes severe skin burns when exposed to sunlight
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Creates dense stands that out-compete native plant diversity
CLOCA'S ACTION
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Removal and follow up monitoring along trails at CLOCA's Conservation Areas.

WATER CHESTNUT*
WATER CHESTNUT
Aquatic plant native to Europe. Prohibited under the Invasive Species Act. Suspected introduction by local property owners releasing backyard pond plants.
IMPACT
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Creates extremely dense floating mats of vegetation, shading out native aquatic plants
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Reproduces vegetatively and by seed
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Hard nuts with sharp, barbed spines can accumulate, impacting recreational water use
CLOCA'S ACTION
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Physical removal at Pumphouse Marsh in Oshawa
This management has been ongoing since 2018. This species has only been found at three other locations in Ontario (Ottawa, Rideau and St. Lawrence Rivers).
We'll come to you!
If you’d like to have us attend your event or provide a presentation to your group, please contact Roy Mosher at rmosher@cloca.com
*Images courtesy of invadingspecies.com
Horizon Scanning: On the lookout for potential up-and-coming...
There is a constant threat of new invasive species emerging as a result of globalization and increased trade between different countries and continents. CLOCA collaborates with ENGOs including the Invasive Species Centre, the Ontario Invasive Plant Council, and both the federal and provincial governments to stay up-to-date on new and emerging pests.
Be on the lookout for some potential up-and-coming invasive species:
Japanese Stiltgrass
Asian Carp
Hemlock Wooly Adelgid
Water Soldier
Images courtesy of invadingspecies.com and entomologytoday.org
WHAT CAN YOU DO?
Plant Native
Where possible, use native plants in your landscaping. Below are links to helpful resources:
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Grow Me Instead - guide for alternatives to invasive horticultural plants
Know Your Invasives
Learn to identify invasive species by visiting the Invading Species Awareness Program or using these great resources:
Report Invasives
If you see an invasive species, report it to EDDMapS Ontario or contact the Invading Species Hotline at 1-800-563-7711.
Stay on the trails
Always remain on designated trails and keep pets on a leash to avoid disturbing natural habitats. Invasive species often thrive in disturbed areas and their seeds can travel on you and your pets. Staying on the trails will also help keep you safe. Learn to identify Central Lake Ontario Conservation's most untouchable plants.
Give them a brush-off
Clean off your footwear and all equipment before you go from one natural area to another. This includes all surfaces of canoes, boats, bikes, fishing equipment, ATVs, walking sticks and evens skis, snowmobiles and snowshoes in the winter.
Volunteer
To participate in CLOCA work days, contact Yvonne Storm at ystorm@cloca.com or sign up for our newsletter for regular updates on volunteer events.
To participate in Phragmities removal events at Heber Down Conservation Area, contact Roy Mosher at rmosher@cloca.com.
Educate your class
Grades 9-12: Participate in the To Beat it We Eat it program at Purple Woods Conservation Area. In this program high school students have the opportunity to learn about the invasive garlic mustard, remove it from the forest and head to the kitchen to make some delicious garlic mustard pesto. For more information, contact Roy Mosher at rmosher@cloca.com
Managing your own property?
The Ontario Invasive Plant Council has developed a suite of resources to help you manage invasive species on your property:
Don’t know where to start? Contact Roy Mosher at rmosher@cloca.com
Additional Resources
The Ontario Invasive Plant Council has developed a suite of resources to help you manage invasive species on your property: