Purple loosestrife

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• Grows 1-2 m tall
• Numerous erect stems growing from a single woody root mass
• 3–10 cm long and 5–15 mm broad Leaves
• Reddish purple flowers
• The fruit is a small 3–4 mm capsule containing numerous minute seeds
• Producer

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• Native to central and southern Europe, Great Britain, central Russia, southeast Asia and northern India.

The highly invasive plant was likely introduced when its seeds were included in soil used as ballast in European sailing ships and discarded in North America. The plant was also spread by early settlers and is still used in flower gardens and occasionally sold in nurseries today.

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• Purple loosestrife was first introduced to the Atlantic coast of North America. From there, it spread westward across the continent to Canadian provinces and American states except Florida, Alaska and Hawaii. In Ontario, the plant has spread widely throughout the Great Lakes-St. Lawrence River Basin, and to scattered locations in the north around cities and towns such as Timmins, Geraldton, Sioux Lookout and Rainy River.

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An invasive species is defined as an organism (plant, animal, fungus, or bacterium) that is not native and has negative effects on our economy, our environment, or our health.

Purple loosestrife has become a serious invader of wetlands, roadsides and disturbed areas. The plant forms dense stands with thick mats of roots that can extend over vast areas. The stands reduce nutrients and space for native plants and degrade habitat for wildlife. Each plant can grow as many as 30 flowering stems that can produce up to 2.7 million seeds each year. The tiny seeds are easily spread by water, wind, wildlife and humans.

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By crowding out native plantsit reduces biodiversity.

Large stands of purple loosestrife can clog irrigation canals, degrade farm land and reduce the forage value of pastures.

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• Human- Source of income
• Environmental- Biodiversity
• Economic

In 1992, the Canadian and American governments approved the release of two European leaf-eating beetles, s and G. pusilla. The beetles are natural enemies of purple loosestrife and feed primarily on the plant, although they occasionally eat other species of loosestrife. This biological control of purple loosestrife can reduce populations by up to 90 per cent and allow native plants to re-establish. The beetles were widely released in Ontario, and purple loosestrife populations at many of these sites have been significantly reduced.

One horizontal underground stem, known as a rhizome, can produce 30 to 50 erect stems. The stems are woody and square, and each one can form a plant up to 2.4 metres high and 1.5 metres wide.

Individual flowers have five to seven pink-purple petals about 10 millimetres long, arranged on long flower spikes at the top of stems.

Leaves are opposite or whorled and three to 10 centimetres long, with smooth edges.

Fireweed

Blue vervain

BLazing stARS

Learn how to identify purple loosestrife and other invasive plants.


The best time to remove purple loosestrife from your garden is in June, July and early August when it is in flower.
To dispose of purple loosestrife, put the plants in plastic bags, seal them, and put the bags in the garbage.
Avoid using invasive plants in gardens and landscaping. Buy native or non-invasive plants from reputable retailers.
When hiking, prevent the spread of invasive plants by staying on trails and keeping pets on a leash.

If you find purple loosestrife or other invasive species in the wild, please contact the Invading Species Hotline at 1-800-563-7711, or report a sighting online.

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