Invasive Species



Invasive species are a threat to the health of Ontario's natural environment. These non-native species are aggressive in nature, moving into natural areas and gradually crowding out and killing off native species. The result can be a gradual decline and, ultimately, the extinction of native species.

Several invasive species known to be present within the boundaries of the Town of Whitby are described below. 

Giant Hogweed and Wild Parsnip

Giant Hogweed and Wild Parsnip are both invasive perennial plants belonging to the carrot family, native to Europe and Asia.  Both are found in many areas throughout southern Ontario, and are now widespread in Whitby's naturalized areas, particularly along stream banks, roadsides and disturbed open areas.  The sap from these plants can make skin extremely sensitive to sunlight, and can cause a burn-like rash. 

What the Town is Doing

Due to the number of plants and area involved, total removal of the plant is not an option. To protect trail users, trained Town staff have installed warning signs and are applying herbicides to plants located within a three (3) metre buffer area along the trail.

What You can Do

Avoid all contact with this plant. Learn to identify the plant, and keep children and pets away from them.  Stay on established trails at all times.  If you do come into contact with the sap:

  • Immediately wash the skin thoroughly with soap and water
  • Avoid further exposure of the affected skin to UV/sunlight
  • If a burn like rash appears seek medical attention
  • If there has been direct exposure to the eye, immediately flush the eye with water and seek medical treatment on an urgent basis

If you suspect you have Giant Hogweed or Wild Parsnip on your own property, it is recommended that private landowners hire a licensed professional to identify and remove the plant to ensure safe procedures are followed.

Suspected findings of Giant Hogweed and Wild Parsnip on Town property should be confirmed by contacting the Town of Whitby at 905.669.3437  or


  • Identification
  • Giant Hogweed fact sheet
  • Wild Parsnip fact sheet

European Fire Ant

The European fire ant is a non-native, invasive species that is a nuisance pest for people and pets.  They will aggressively defend their territory by stinging.  The sting is similar to that of a bee or wasp.  In rare cases anaphylactic shock may occur, requiring immediate attention.

The European fire ant prefers warm and moist outdoor conditions that provide favourable habitats to establish nests and to forage.  Reported infestations in Whitby have been limited to natural areas and those residences backing on to them.

What the Town is Doing

There are no known effective, long-term control methods available for parkland and natural areas.

What You Can Do

When travelling through parkland and natural areas you are advised to:

  • Stay on designated pathways and trails
  • Wear covered footwear and long pants to protect yourself from all stinging insects and hazardous plants
  • Keep dogs leashed and on designated trails.

On private property:

  • Remove potential nest sites such as leaves, logs and other debris from your property
  • Reduce moist conditions by reducing irrigation and increasing exposure to the sun by mowing tall grass and pruning overhanging tree and shrub branches
  • Carefully inspect all plant and nursery materials including plants, trees, soil, compost, wood chips and logs prior to installation on your property
  • Call a professional if European fire ants are a nuisance on your property.