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St. Albert Area’s Invasive Plants and Insects

July, 2016

We plant things because we either need to eat them or because they look pretty. However, some of those pretty things can be dangerous to our ecosystem. Before you plant or let that unknown shoot grow to maturity, here’s a small list of what the City of St. Albert and the province have deemed invasive in plants and insects.



  1. Purple loosestrife: Originally from Europe and Asia, this invasive plant depletes soil nutrients, reduces space for native plants to grow and for animals to thrive, and clogs up wetlands. One plant produces approximately 30 flowering stems and nearly 3 million seeds. It has woody, square stems with fuzzy, purple flower spikes. Mature plants are next to impossible to remove, so pull this plant when it is young and its roots are not established. Put the pulled plants immediately into a bag that’s destined for a landfill.


  1. Garlic mustard: Native from Europe and Asia, this plant was brought over to be used in cooking, as it’s high in vitamins A and C. However, the seeds were dispersed into woodland areas where it’s taken over the habitat of native flora and fauna. The plant is dark-green and spreads like a ground cover. Its flowers grow in white clusters that have four petals and smell like garlic. It doesn’t survive extensive tilling, and it can be smothered with a good layer of wood-chip mulch.


  1. Himalayan balsam: Originally from the western Himalayas, this invasive plant has a shallow root system and can be pulled easily. When the flowers are touched, the seeds—up to 800 per plant—are ejected as far as five metres. Due to its great seed dispersal, it can easily overtake natural plants’ habitat. The plant grows 1–3 m tall, is purplish-red and its flowers resemble snapdragons (purple, white or pink). If the plants are mature, place a bag over them so you can catch any seeds that are ejected. The best disposal options are incineration or a landfill.

For more information on invasive plants, check out the City of St. Albert’s website or Alberta’s website for invasive plant identification.



  1. Grasshoppers: Grasshoppers will eat all sorts of vegetation if there isn’t a sufficient food source, which is why they can devastate cereal crops, namely wheat and barley. In the past, clear-winged and migratory grasshoppers have eaten huge areas of range grass and hay. Their natural enemies are bee flies, crickets, birds, blister beetles and ground beetles; some spiders and wasps also feed on grasshoppers. During the Depression, farmers let turkeys loose in their fields to eat grasshoppers. Because the insects are high in protein, the turkeys didn’t need additional food supplements.


  1. Wheat midge: Areas east of Edmonton have had high concentrations of this insect. They look like a smaller, orangey version of a mosquito. They lay their eggs in the wheat head so that the larvae have a ready food source the moment they hatch. The damage isn’t readily apparent, so detection of wheat midge damage can only be done by personally inspecting the developing seeds. They can severely decrease the yield and the grade of the wheat crop. To keep ahead of the insect, control and monitoring must be done daily. A small, parasitic wasp is a natural enemy of the midge, or if the soil is contaminated with wheat midge adults, it’s recommended to switch to less susceptible crops, such as oilseeds or pulse.



  1. Goldfish: These discarded pets have seriously altered the aquatic diversity in Edgewater Pond and are outcompeting insects, plants and other fish for food and oxygen. Goldfish procreate prolifically and can survive in many types of water. They’re not native to Alberta; therefore, they don’t belong in Alberta’s waterways. The problem was first discovered in October 2015. Monitoring of the pond has revealed that the goldfish haven’t yet found their way into the Sturgeon River.

For more information on invasive insects, check out Alberta’s agricultural website.

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