Invasive plants in High Park

Invasive plant species pose some of the greatest challenges to the preservation and restoration of High Park's natural environment. To learn more about how City staff and volunteers are dealing with these species, see Controlling Invasive Plants and High Park Stewards.

Greater Celandine Field. Photo: Sharon Lovett
Greater Celandine Field. Photo: Sharon Lovett

Herbaceous Plants

  • Dog-strangling Vine
  • Garlic Mustard
  • Sweet-white Clover
  • Himalayan Balsam
  • Purple Loosestrife
  • Greater Celandine
  • Japanese Knotweed
  • Hedge Parsley

Shrubs & Trees

  • Common/European Buckthorn
  • Euonymus
  • Asian Bittersweet
  • Tree of Heaven
  • Norway Maple

See also Phragmites

Is this plant native or invasive?

Test your knowledge: guess first and then move your cursor over the photo (or touch the photo) to check your answer.

Canada Anemone

Garlic Mustard

Purple Raspberry

Himalayan Balsam

White Sweet Clover

Meadow Rue


European Spindletree

Black Oak

Norway Maple

Greater Celandine

St John's-wort


Tartarian Honeysuckle

Glossy Buckthorn

Japanese Knotweed

Garlic Mustard field. Photo: Sharon Lovett
Garlic Mustard field. Photo: Sharon Lovett

Invasive Plants Resources

Quick guides

References and documents

More resources and websites

Articles, Galleries and Guides

What's New?

Welcome to Our New Website!

By High Park Nature | September 14, 2020
Since the High Park Nature website was first launched in 2010, it has provided a wealth of information about the natural features of High Park. Now we are pleased to…

New Treatment for Buckthorn

By High Park Nature | July 9, 2020
This summer Urban Forestry is partnering in a demonstration trial with BioForest, a forest pest management company, to manage invasive buckthorn shrubs using the bioherbicide Chontrol Peat Paste. The active…

Toronto Star article, January 13, 2020

By High Park Nature | April 5, 2020
“We love High Park for its natural beauty. Will that love be the death of it?” Read the article or The Star Pressreader version

High Park Christmas Bird Count Results

By High Park Nature | December 27, 2019
The most recent High Park Christmas Bird Count was held on Sunday, Dec. 15, 2019 (a very windy day). The High Park route ended up with 43 species, our lowest since…

High Park Stewards Summary 2019

By High Park Nature | December 1, 2019
There were over 280 participants (between 110 individuals coming at least once) who came out to High Park Stewards field restoration events. The average number of Stewards that attended each…








Trees + Shrubs



Wetland Plants

Invasive Plants