Here Are Some Invasive Species Found In Hamilton Region

European Buckthorn 

The tree was brought to North America by European settlers. As the name implies, European Blackthorn is native to Europe but also native to Northern Africa and Western Asia. European buckthorn has deep roots that are a challenge to eliminate. Another way the trees spread is due to fauna activities, such as birds that like to eat the fruit they take with them, which eventually, some of them drop and form a new one with the fruit’s seeds. You can remove it by pulling; excavation is best done when the soil is misty. 

Native Alternative:  Nannyberry Shrub

A bush with exceptional white flowers in the spring, deep burgundy leaves in the autumn and blue berries in the winter that is easy to grow and spreads widely and likes sunny locations.

Garlic Mustard 

Early in the nineteenth century, it was transported to North America for usage as a herb that can be eaten. It has a robust and unmistakable smell akin to garlic and is readily available in the early spring. It is also rich in vitamins A, and C. Garlic Mustard is a plant with leaves with sharp serrations, resembling a heart and little white flowers that can reach a height of one meter, with a crossed shape during April and June. Hamilton’s biodiversity is in danger due to the toxic pollutants it discharges into the surrounding soil, which can spread up to 20 feet annually. Garlic Mustard that has been picked after it has bloomed can still spread its seeds that can be stored for up to 20 years, so the plant should be “solarized” to ensure it is completely dead. Do not throw the plant into compost; instead, you can get rid of it by putting live plants in sealed plastic bags and exposing them to direct sunshine for 1-3 weeks.

Native Alternative: Wild Ginger

This plant is suited for shady places. It grows low on the ground and has a height of around 15 cm. The leaves are prominent in diameter and heart-shaped. Surprisingly the root of Wild Ginger is edible and tastes just like regular Ginger, yet more wood-like. The plant’s flowers are positioned at the base of the stem closer to the ground and are brownish in colour. 

Japanese Barberry 

This shrub is Native to Japan, Asia and was brought to North America closer to the end of the 18th century. It has small, oval, pale yellow flowers that dangle from the prickly branches. From mid-summer to the beginning of the winter, the bright red berries make Japanese more distinctive and identifiable. Its height can reach up to 6’ tall with smooth leaves. You can eliminate the plant by pulling the roots or seeds out of the moist soil. 

Native Alternative:  Northern Bayberry

Northern Bayberry has small leaves that are lanceolate in shape. The flowers, clusters of dull yellowish-green colours, bloom between April and May. They also have berries, but they are small, pale gray to silver, mature in August, and last into winter.

Multiflora Rose

Multiflora Rose is a fountain-shaped woody and thorny shrub that grows up to 15’ tall and is native to Eastern Asia. Originally it was introduced to North America from Japan in the mid 18 century. You can find this woody shrub in areas with a lot of sun, such as roadsides, on the edge of forests and fields. This plant can grow aggressively, frequently towering over and surpassing local biodiversity. These invasive species are spread by their roots and canes. As there are no natural predators, it is easier for them to outcompete native plants, taking up most space. The best way to eliminate this invasive species is by digging, pulling and cutting the shrub to a stump. 

Native Alternative: Rose Blanda or Smooth Rose

Smooth Rose is a native shrub to Ontario that has pink flowers that bloom from July and last all the way to the winter and has green-blue leaves. 

Japanese Knotweed

According to the plant name, Japanese Knotweed was initially brought from Japan to North America for garden erosion control. However, they are highly threatening to the native biodiversity of Ontario and Hamilton. This semi-woody perennial spreads by its roots, seeds, and even plant fragments, making it extremely hard to remove altogether. When Remington is an invasive species, it is essential to clean all the remains as they spread quickly in dirty and contaminated environments. Due to the challenges regarding removing these species, the Canadian Government prohibits legally planting the plant. 

English Ivy

English Ivy is Native to Western Asia, Europe, and Northern Africa. This evergreen invasive species is mildly toxic and can harm humans, animals and other plants. Following exposure to the plant and the berries it produces, some individuals can experience dermatitis, which irritates the skin. The plant can be identified by its big and glossy leaves, usually medium in size with white, yellow or green veins. These species are hard to remove as they need to be pulled out by the root, and the roots are long and spread very quickly. 

Native Alternative: Virginia Creeper

In compassion to English Ivy, it is taller as it can reach a height of 40 feet and is found in Ontario and Quebec. It typically has five leaflets per leaf, which become red in the fall. Like English Ivy, it produces toxic berries that are not harmful to birds yet can be detrimental to humans as it contains microscopic crystals that irritate your mouth. Little fruit that many birds enjoy eating, but humans should not consume it because it is harmful.

Lily Of The Valley

This plant is native to Asia and Europe. It can grow up to 18 cm tall. Lily Of The Valley leaves are large with smooth edges, and some white flowers on stems are comparable to little bells. It also produces red berries that are as poisonous as the rest of the plant and should not be consumed otherwise, be prepared for headache, nausea, abdominal pain and vomiting. The plant is okay with full shade and full sun areas. However, it prefers partially sunny spots. It spreads by roots as it grows from rhizomes that are located underground. The best way to remove the plant is by digging about 2 feet, removing all the roots and rhizomes, or limiting all the surrounding sunlight until the plant completely dies off in a couple of years.

Native Alternative: Canada Mayflower

Canada Mayflower looks similar to the Lily Of The Valley but with two glossy oval leaves. It also has tiny white flowers located on separate stems.

Wild Parsnip

The plant is native to Asia and Europe. European settlers brought it to North America, where they farmed it for its edible root since it is a carrot family member. It reaches up to 5 feet. The stems, as well as the leaves, both have hairs. Wild Parsnip leaves are sharp and toothed. It also has umbrella-shaped yellow flowers that grow in clusters. It is found primarily on fields, trails, forests and waste areas as the plant loves the sunlight and will grow anywhere close to the sun, although they do not shy away from shade either. Do not touch the plant, as it is extremely toxic. Stem, leaves, and flowers all contain toxins such as furanocoumarins which, when in contact with skin, can cause blisters, rashes, and skin burns if you expose the skin to the sun. Stay on trails, learn to identify Wild Parsnip when you see one, and wear long sleeves and pants. To get rid of these plants best way possible, use a shovel or spade to break the tap root.

Native Alternative: Cow Parsnip

It resembles the plant with smaller white clustered flowers and thicker ribbed stems. It can grow up to 8 feet tall. Like the invasive parsnip, it contains a toxic compound called furocoumarin that can cause similar effects such as rush, burn and headaches.

Strangling Dog Vine

This plant is native to Eurasia and is considered an invasive plant in Ontario. This perennial vine has an annual growth rate of more than 6 feet. It blooms brown-purple flowers from May to July. It expands through rhizomes that grow beneath the ground and its feathery seeds that can spread by the wind. Monarch butterflies mistake the vine for milkweed and are at risk. The butterflies lay their eggs on the plant, but the eggs do not hatch into larvae, who do not survive. Since these species must be dragged out by the roots, which are lengthy and spread readily, removal of is Dog Strangeling Vine is labour intensive. 

Native Alternative: Trumpet Vine 

This plant is only native to Ontario, making it unique native species. These vines grow in places with full or partial sun. Trumpet vines need support; therefore, they should be attached to a trellis or a fence.