HWA found in Nova Scotia 

Hemlock woolly adelgid was confirmed in Nova Scotia this summer. The infestation is widespread in five counties and was likely present for over ten years before detection, according to Matthew Smith, an ecologist at Kejimkujik National Park. There's significant hemlock mortality at one site near Yarmouth.

Its not clear how HWA arrived in Nova Scotia - possibly hitchhiking on birds or carried in a wind event. Humans are always a potential suspect. But many of Nova Scotia's old-growth forests have an important hemlock component, and may be threatened by the adelgids. The photo above shows very old hemlocks in Kejimkujik National Park (photo credit Matthew Smith).


First detection of HWA in Adirondacks

This summer something happened that many forest ecologists have been awaiting with dread: HWA was confirmed in New York's Adirondack Mountains. The Adirondacks are known for having abundant (and commonly old-growth) hemlock forest, so detection of adelgids there is obviously of great concern.

In October the infested trees, and a buffer of trees around them, were treated with insecticides - this is the best control measure for HWA (cutting trees is not considered effective) and will hopefully slow the spread of HWA in the Adirondacks. Vigilance by the public can also help control the spread of HWA - the telltale woolly masses on the underside of twigs are visible roughly Nov-July. 


The hunt is on for Ontario's oldest hemlock trees

 Ancient Forest Exploration & Research is seeking out the oldest hemlocks in the province, in anticipation of the arrival of HWA. Michael Henry, an ecologist with AFER, says he expects to find trees over 400 years old, and hopefully beat the current Ontario record of 460 years - but the odds of finding old trees are increased by knowing what to look for. "We're using visual cues that anyone can learn to recognize, to choose the trees that we want to age," Henry says. These signs of old age include sinuous (curved or snake-like) trunks, large upper branches, and trunks with very little taper. Trees that are believed to be old are aged by extracting a tree core (a pencil-shaped section of wood) so that annual growth rings can be counted. Knowing where old-growth hemlock forests are found can help prioritize areas for conservation once HWA establishes in the province. If you think you know where an old hemlock is located, send an email to info@ancientforest.org.


Biocontrol rearing facility established at Cornell

New York State Hemlock Initiative is now the home of a Hemlock Woolly Adelgid (HWA) Biological Control Research lab, the focus of which is to study the rearing, establishment, and spread of HWA predators to provide long-term management of HWA throughout New York. The establishment of the lab is a huge step forward for New York State, and also has implications for Canada. 

"Insects we are currently studying are Laricobius nigrinus (Coleoptera: Derodontidae) and the silverflies Leucopis argenticollis and L. piniperda (Diptera: Chamaemyiidae), from the Pacific Northwest," the website states. "It is our hope that they will have a widespread impact on HWA and offer long-term survival for eastern hemlock populations without continued use of chemical controls." Some of the achievements of the NYS Hemlock Initiative include:

• Spring 2017: Released nearly 2,000 Leucopis spp. silverflies at 10 sites in New York State, with successful establishment at all sites

• October 2017: Trip to Pacific Northwest to collect Laricobius nigrinus beetles for lab colony, hopefully with some leftover for wild release

• November 2017: Official opening of biocontrol research facility at Cornell University


Biocontrol appears to be working in New Jersey

Laricobius nigrinus beetles were first released in New Jersey in 2005, and more than a decade later they have dispersed to many areas where HWA are found and they appear to be controlling the adelgids. In a northjersey.com article Mark Mayer of the New Jersey Bureau of Biological Pest Control says that “Pretty much every hemlock stand north of Route 80 and west of Route 287, if you’ve got adelgid in there, you’re going to find beetles. I think right now, it’s not getting worse [and] where we first released the beetles … those trees are looking pretty good.”


HWA detection season longer than we thought?

This striking photo above, taken August 10 in Nova Scotia, by Matthew Smith, shows the wool of HWA very clearly despite being very late in the season. Ideal HWA detection season is late winter through spring / early summer, but it's worth keeping in mind that wool may be present from late October to mid-July or even later - for at least nine months of the year HWA can be spotted by flipping over the branches and checking for wool at the base of the needles. In many places members of the public have been the first to detect HWA - so check for it when you're walking in hemlock woods from now through July.


This newsletter was brought to you by Ancient Forest Exploration & Research. Please forward it to anyone who might be interested.

Send us details of old-growth hemlock forests that you know of by email to info@ancientforest.org, and / or add them to our inaturalist project.

To learn more about HWA in Ontario or to sign up for this newsletter go to http://www.ancientforest.org/hwa/ and to learn more about how and when to monitor for HWA go to  http://www.ancientforest.org/monitoring-for-hwa-how-and-when/