You and the Hemlock Killing Bug - HWA


A little bug called the hemlock woolly adelgid (HWA) is decimating our Nova Scotian hemlock forests.  

This article is all about simple steps you can take to help prevent the spread.

For some awesome images of Nova Scotia's hemlock forests, check out our social media pages ( Instagram ) ( Facebook )

The Canadian Food Inspection Agency's video above does an excellent job of informing us about what we're up against.  See below for the contact information for people to Nova Scotia.

And if you would like to learn more about hemlock woolly adelgid, checkout the free, open to all webinar titled "Hiking the Trails to Save Hemlocks".  Register at :

How can you find HWA?  

There have been positive hemlock woolly adelgid (HWA) sightings throughout western Nova Scotia up to a line running from Mahone Bay to Wolfville.  

Is it further east?  This is where you can help!  And right now is the best time to find it.

HWA builds a cotton-like sac on the underside of hemlock branches where the needles meets the stem.  There are several ways to find it:

Grab a branch, turn it over and look for the cotton-like sacs

A fallen branch provides an excellent opportunity to inspect branches that would normally be higher up in the tree

After a wind or ice storm, you will commonly find tips of hemlock branches strewn on the ground.  If the underside of the branch is facing up you can inspect for HWA simply by looking down!

Other options include:
  • using a very bright, focusable light that you shine up into the tree around dusk when the white woolly sacs will pop in the light
  • using a pole saw to cut samples higher up on the tree

If you think you have found HWA, please let us know!  Early detection means there are more treatment options.  We're particularly interested in the leading eastward infestation edge which runs from Mahone Bay to Wolfville. (Hey HRM, that's you!)

To report a sighting, you can:

Send an email to and please include a pic which helps us verify it is HWA

Are you an iNaturalist user?  Simply post it identified as hemlock woolly adelgid

Send you sighting to the Canadian Food Inspection Agency.  This is a good option if you would prefer not to disclose the location

You will find hemlock trees in every county in Nova Scotia.  Here are some of our favourites.  Have you visited any of them?  Perhaps you have a fav?

Please help us find HWA as it moves eastward across the province.

And once the weather warms up and HWA starts to move, please take steps to ensure you do not move HWA from an infested forest -- like Keji -- to another hemlock forest -- like Victoria Park in Truro.  Thousands of babies can fall from a single infested tree and it only takes one to start a new population.

So between April and the end of July when in a hemlock forest, please :

1- use a lint roller to wipe down yourself and your pooch as you leave a hemlock forest
2- a quick clothing change makes sure there are no hitchhikers.  10 minutes in the dryer kills HWA
3- avoid placing your gear or parking under hemlock trees
4- acquire your firewood where you burn it

Thank you for your help!

Keji's Hemlock and Hardwood Trail (c) Martin Gray

Wentzell Lake Park (c) Tom Rogers

Truro's Victoria Park @capturesbycarriepink