Aerial spraying for moth outbreak begins in Toronto this week. Here's where it's happening

A caterpillar of the Gypsy moth is seen on a leaf in Tiny Township, Ont., on Fri., July 10, 2020. (Roger Klein/CTV News)

The City of Toronto will start aerial spraying this week to combat what they call "outbreak levels" of moths.

The LDD moth, formerly known as the European Gypsy Moth, feeds on trees, which the city says results in severe leaf loss. This makes the trees weak and vulnerable to diseases and extreme weather conditions.

Officials said the first aerial spraying took place on Tuesday in the following areas:

  • Beaches-East York
  • Scarborough Southwest
  • Scarborough-Agincourt
  • Scarborough North
  • Scarborough-Guildwood
  • Scarborough-Rouge Park

The second round of spraying will take place 10 days later and come to a close by mid-June.

The spraying involves three twin-engine helicopters flying between 15 and 30 metres above the tree canopy and releasing insecticides, which take effect once the LDD moth caterpillars feed on the treated leaves.

The city says the insecticides – Foray 48B, otherwise known as Btk – are a natural bacteria typically found in soil that has been approved by Health Canada. The spray is not toxic to birds, humans, adult moths, butterflies, bees and other insects.

Here are the areas of Toronto that will be sprayed in the coming weeks:

  • York Centre, Don Valley West
  • Don Valley East, Don Valley North
  • Willowdale, Beaches-East York
  • Scarborough Southwest
  • Scarborough Centre
  • Scarborough-Agincourt
  • Scarborough North
  • Scarborough-Guildwood
  • Scarborough-Rouge Park

A different pesticide will be sprayed over High Park to avoid potentially impacting other moth and butterfly species.

The upcoming dates dedicated to spraying will only be confirmed 48 hours in advance and can be cancelled based on weather conditions.

The spraying will take place between 5 a.m. and 8:30 a.m. Residents can access updates on the City's spray schedule, here along with a map.

The city says there are no “special precautions” for people who live in spray zones. However, those looking to avoid exposure are recommended to stay indoors.