A "bad seed", known more formally as an invasive plant, is a non-native plant that was introduced to our environment through seeds, cuttings, garden plants, etc. that spreads aggressively and takes over the natural environment. Bad seeds out-compete native plants, including endangered species, and destroy habitat for fish, birds and other wildlife. Invasive plants can also cause erosion and silt problems in creeks and impact aquatic creatures. Invasive plants are expensive to control and eradicate. Some, like Giant Hogweed, are even dangerous to human health.
Commonly sold as an easy and fast grower that can tolerate shade, English ivy (Hedera helix) smothers vegetation and can eventually kill trees.
English ivy is identified by dull, green, lobed leaves with a thick, waxy coating that stay green all year long. It grows as a small to large woody vine that clings to surfaces such as trees, buildings and rocks.
Giant Hogweed (Heracleum mantegazzianum) poses a serious threat to human health and the environment. The clear sap found in its stem and hairs can result in severe burns and blistering. If sap enters the eyes, it can cause temporary or permanent blindness.
If you find Giant Hogweed on your property, it needs to be removed as per the City’s Noxious Weed Bylaw Number 4181, 2010.
If you are exposed to Giant Hogweed, wash the affected area immediately, keep it out of the sun and seek medical advice.
It is best to let a professional remove this plant.
Sometimes found in wild seed mixes, this very persistent climbing vine will trail along the ground, smother native plants and twist counter-clockwise up supports. The leaves are arrow-shaped with a sharp point and has showy, white trumpet-shaped flowers. The above ground part of this plant dies off in the winter.
Japanese Knotweed (Fallopia japonica) forms dense, tall thickets and can grow up to 3.5 metres tall from a small root or stem, crowding out other plants.
Leaves are spade shaped and small white flowers are produced in clusters.
Periwinkle (Vinca minor), sold as a fast grower, is a trailing groundcover with small waxy leaves smothers native plants.
It has showy purple flowers with five petals and its leaves are pointed and dark green.
Lamiastrum galeobdolon Commonly sold in hanging baskets, lamium is a ground cover that smothers native plants. It stays green year-round with hairy green and white leaves. Small yellow flowers will appear in the spring and summer.
Are you interested in becoming a Bad Seed volunteer?
If you have a group interested in organizing an invasive plant pull with the City, please email the Natural Areas team. If you are an individual looking to join a scheduled invasive plant pull, register with Better Impact and watch for upcoming Bad Seed events.
For more information about our weed pull events, contact us by email .