Journeys in ancient and old growth forests
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Hemlock Woolly Adelgid Survey Letter

logoAncient Forest Exploration & Research

3492 Memorial Park Dr., RR#4, Powassan, Ontario P0H 1Z0; phone: (705) 724-5858


Dear fellow naturalist,

I’m part of a small Ontario-based organization called Ancient Forest Exploration & Research, which specializes in research and conservation of old-growth forests. We’re seeking naturalists and concerned citizens to help in identifying potential arrival sites of Hemlock Woolly Adelgid (HWA) in Ontario. HWA is an introduced pest that threatens Eastern Hemlock with functional extinction across much of its range. In the United States, HWA has spread through much of the Appalachians, resulting in Eastern Hemlock mortality as high as 90-98% in many stands, and it is moving north.

In 2012, HWA was reported for the first time in Ontario; it has been detected in Ontario’s Niagara Gorge, and in Oswego NY, about 110 km from the St. Lawrence Seaway and Canadian border. Since it can be carried by birds and humans, it is not certain what its current distribution is; HWA could be detected again at any time in the Niagara region, or in Kingston and surrounding areas. Our best hope for preserving Eastern Hemlock on Ontario’s landscape is to detect the arrival and spread of the HWA as early as possible.

Early detection of HWA allows for use of biocontrol agents (often in combination with systemic insecticides), whereas waiting for obvious signs of infestation results in high tree mortality.  Preserving old-growth forest is the best way to maintain the genetics of this species for recolonization of the landscape once effective biological control is established, therefore we are especially interested in locations of old-growth forests with a significant Eastern Hemlock component. We’ve written an article about the northward spread of HWA at

We are using a variety of data sources to locate Eastern Hemlock stands.  The field knowledge of amateur naturalists and professional ecologists will be invaluable to this project. Once we have identified priority areas for monitoring, we will publish this information and share it with the Canadian Food Inspection Agency, HWA land manager working group for Ontario, and MNR, which are involved in monitoring for the pest. We will also share our findings with your naturalist group, and provide educational materials to assist naturalists and concerned citizens with monitoring for the pest.

AFER would like your help to:

  • identify concentrations of Eastern Hemlock trees, and locations of old-growth Eastern Hemlock forests in Ontario, particularly those close to the U.S. border;
  • share the results of our study;
  • participate in citizen monitoring of the sites.

Please send us as much information as possible about the location of Eastern Hemlock forests, including whenever possible:

  • GPS location,
  • map address,
  • approximate size,
  • ownership and access details,
  • estimated percentage of Eastern Hemlock,
  • estimated age,
  • any relevant references or websites, and
  • whether you or someone you know might be interested in monitoring for HWA.

Thank you for your time and I look forward to hearing from you. You can reach us by email at

Michael Henry