Dutch Elm Disease (DED) is a deadly disease for trees caused by a microfungus that is easily transported by bark beetles. Symptoms of DED include drooping, yellowing leaves, and defoliated branches. These symptoms will eventually lead to the death of the affected elm tree.

Edmonton has one of the largest populations of uninfested American elm trees in the world, and we rely on Edmontonians to monitor and protect these beautiful boulevard trees. As per the Community Standards Bylaw, elms may only be pruned between October 1 and March 31. This is because fresh cuts and broken branches may attract beetles during the warmer months. Also, please do not transport elm wood from one place to another as this increases the risk of introducing DED to our elms.

If you have any concerns regarding potential DED on a City or private elm tree, please report it by calling 311 or using the Edmonton 311 app.

Over the last several years, particularly with information spread over social media, Edmontonians have become more concerned about the potential of encountering ticks as they enjoy nature. Ticks are small spider-like animals (arachnids) that bite to fasten themselves onto the skin and feed on blood. While most ticks do not act as carriers for diseases, even the most innocuous can be a nuisance at best and are often extremely distressing to discover. While extremely rare, there is evidence to suggest that incidences of Lyme disease are on the rise in Alberta, so it should be taken seriously. However, there is no evidence that ticks capable of transmitting Lyme disease have formed established populations in Alberta; they likely are adventitious (e.g. brought into the province on migratory birds or animals).

You can minimize your exposure to tick bites with a few simple steps:

• Wear light-colored clothing, with long sleeves and pants. Tuck your pant legs into your socks for increased protection
• Walk on cleared trails rather than through bushes or tall grass
• Use an insect repellent containing DEET or Picaridin
• Always check yourself, your children, and pets for ticks after excursions in the wild

Native to Asia, giant hogweed is a prime example of an invasive plant that causes harm to human health. The toxins in the sap can cause severe skin inflammation and burns. We receive many inquiries about this plant every year and all reports have proven to be a native plant called cow parsnip, which can look quite similar at its vegetative stage.

How do you tell the difference between cow parsnip and giant hogweed? Giant hogweed grows up to 5.5 m tall, has stiff hairs on its stem and its leaves are shiny, deeply lobed with a serrated edge. On the other hand, cow parsnip is 1 - 2.5 m tall and its leaves are less serrated. Please do not touch cow parsnip as its sap could cause rash as well. If you are unsure which plant you’ve spotted, send a weed ID question to us on the 311 app!

You may have seen boot brush stations in national parks and wondered what they are for. These stations are designed for you to brush off any seeds from invasive species that may be stuck on the bottom of your shoes. In southern Illinois, a study was conducted to determine their effectiveness. 39 species were found under the brushes, while 14 of these were non-native plants. The study also found that seeds from under the boot brush are very different from the ones along the path where the station is, which means these seeds have been carried by human traffic from other areas. In conclusion, the data suggested that the boot brushes are removing a lot of seeds from the bottoms of shoes and are helping to stop the spread of invasive species! 

Did you know that invasive species is the second biggest threat to biodiversity globally? You can help protect biodiversity in Edmonton by simply brushing off the bottom of your shoes before leaving or entering a natural area.