Weed Inspection

The Provincial Noxious Weeds Act, R.S.O. 1990 is concerned with the control of noxious weeds that interfere with lands used for agricultural and horticultural purposes. Under this Act, all landowners are required to destroy any noxious weeds and weed seeds on their property. The intent of the Act is to: 

  • Reduce infestations of noxious weeds that can impact agricultural or horticultural crop yields.
  • Reduce plant diseases that can impact agriculture or horticultural crop yields by eradicating host plants.
  • Reduce health hazards to livestock cause by poisonous plants.

If you own property of ten acres or less, noxious weeds must be destroyed by June 1 and throughout the season. The municipality may otherwise enter the property and have the weeds destroyed, charging the costs against the land as set out in the Weed Control Act.

Notice to control noxious weeds and weed seeds can be served to owners of properties over 10 acres by issuing an “Order to Destroy Noxious Weeds or Weed Seeds”.

There are 25 species on the noxious weed list.

Red berries on a leafed tree

Common Barberry

Berries that are egg-shaped and measure up to 1.2 cm (0.5 inch) long. Shrub may grow up to 3 m tall. Simple, alternate leaves that are often clustered on the stem.
Smooth bedstraw weed

Smooth Bedstraw

Flowers are small and contain four white petals. Stems can be 25 to 120 cm (10 to 48 inches) long. Narrow leaf blades, each with a pointed tip.
round black berries on a branch with a few green leaves

European Buckthorn

Produces clusters of berry-like black fruit in late summer and fall. Often grows two to 3 m tall. Smooth, dark green leaves are finely toothed, 2.5 to 6 cm long, and arranged in opposing pairs along the stem.
Wild chevril weed

Wild Chervil

White flowers with 5 petals are produced on the top of the stem. Can grow to an average height of 1-4 feet. Leaves are alternate and fern-like, divided into many leaflets.
Small yellow flowers against a blue sky


Flowers resemble dandelion but are smaller and have disc florets and numerous, radiate, yellow ray florets. Plant is 5-50 cm tall. Leaves are heart-shaped and 5-20 cm long.
Common Crupina pink flower

Common Crupina

Flowers that are a pinkish-purple and are approximately 1.3 cm long. Can grow up to 1 m tall. Leaves have coarse, rough edges.
Field with long blades of Woolly Cupgrass standing tall.

Woolly Cupgrass

A 30-200 cm annual grass. Dark green, hairy leaves that have a velvety feel.
Dodder green plant

Dodder spp.

Parasitic plants with very thin, string-like twining stems that appear to be leafless. Cover their host plants in a spreading, tangled mass of intertwined stems.
Vine with purple flower, each with five petals, growing from it.

Dog Strangling Vine/Dog Strangling Vine (Black)

Perennial vine with opposite leaves. Small purple flowers that develop into narrow pods with several seeds.
Tall blades of Jointed Goatgrass stand tall in a field with blue skies in the background.

Jointed Goatgrass

An annual grass, 40-60 cm tall, often mistaken for wheat
large green stem with white flowers branching outwards

Giant Hogweed

Flowering head is umbrella-shaped and 40-60 cm wide, with white petals. Stem grows up to 4.5 m tall and 10 cm in diameter. Leaves are divided into three broad leaflets that are deeply lobed and toothed.
small purple flowers

Knapweed spp.

Flower heads are round, 3–4 cm in diameter and made up of several slender purple petals. Grows up to 1.5 m tall. Leaves are alternate, slender and wiry, and grey-green in colour.
three green leaves on a stem


Climbing vine with stems that can grow 10–30 m in length. Its hairy leaves are composed of three leaflets. Kudzu flowers are clustered, fragrant, and reddish-purple.
Wild parsnip

Wild Parsnip

Yellowish green flowers form umbrella-shaped clusters 10 to 20 centimetres across. Grows up to 1.5 metres tall. Leaves are arranged in pairs, with sharply toothed leaflets that are shaped like a mitten.
Poison hemlock small white flowers

Poison Hemlock

Flowering head is umbrella-shaped, comprised of many individual flowers that are white with 4–6 petals. Grows 1-2 m high. Leaves have many leaflets and sharply toothed margins.
Poison Ivy three green leaves per stem

Poison Ivy

Leaves have three pointed leaflets. They are reddish when they appear in the spring, turn green during the summer, and become various shades of yellow, orange, or red in the fall.
Ragweed plant

Ragweed spp.

Erect, hairy and branched stem up to 1.5 m in height. Opposite leaf orientation, deeply divided, densely hairy but short hairs. Flowers from August to October.
Tansy Ragwort weed of yellow and orange flowers

Tansy Ragwort

clusters of yellow flower heads with an orange center surrounded by several thin, yellow petals. Grows as tall as 1 m. Leaves somewhat resemble kale.
Sow thistle weed

Sow Thistle spp.

Flower heads are yellow, 2.5–4 cm in diameter and similar in appearance to those of dandelion. Leaves are elongated, wavy toothed and have a prominent white central vein.
Whispy green grasslike cypress spurge

Cypress Spurge

Flowers are yellow-green clusters at the top of the plant. Grows between 10 and 60 cm. Has slender, lance-shaped leaves that grow out of the stem alternately in a spiral pattern.
Leafy spurge

Leafy Spurge

Small yellow flowers. Leaves are narrow with smooth edges and are attached directly to the stem.
Bull Thistle close up

Bull Thistle

Flower heads are round to pear shaped; florets are bright purple and come out at the top. Leaves are dark green; the upper and lower surfaces are covered in dense, white hairs.
Canada thistle close up, green spiky plant with bright pink flowers

Canada Thistle

Each plant has numerous purple flower heads that can range from 0.5-2 cm in diameter. Leaves are irregularly toothed and have very sharp spines along the leaf margins.
Serrated Tussock grass

Serrated Tussock

Perennial grass with thin, bright green, hairless leaves that have small, easily felt serrations along their edges. Each plant can grow to up to 70 cm tall.