Invasive SpeciesHemlock wooly adelgid

Adelges tsugae
FOUND by Akanoti
ID Confirmed
Quality checked by amk
Peer reviewed by
Field Notes
The survey conducted by University of Maine-Orono Forest Insect and Disease Class and Maine Forest Service staff. It capped a day spent in the woods learning about forest insects and diseases. We spent some time at the site talking about hemlock woolly adelgid and predator beetles, then familiarized ourselves with the signs of adelgid. Conditions were not ideal: light was low (cloud cover significant, late in the day) and adelgid wool was tattered and old. We decide to continue with an abbreviated survey and walk into the stand to a stonewall that runs ~perpendicular to the long axis of the property. We spread out in 4 groups and begin a line-intercept sample of hemlocks (hemlocks with branches within reach along a transect are inspected for presence of HWA). The groups find (infested/total): 12/20, 14/44, 6/14, 12/31 or just over 40% of the trees examined with readily detectable adelgid.
Supporting Evidence
Photo of my evidence.
September is a bad time to scout for HWA. Wool is about 3 months old, and weather beaten. However, if you can find tatters of wool,HWA presence can often be confirmed by searching for settled nymphs on the current-year's hemlock twig growth. They look like little black sesame seeds, ringed with a fringe of wax. A means of magnification is important for adelgid hunters! Note photos are not of the Sept 2013 field visit, but are what would be seen that time of year (except site photo, which is from May 2013 at survey site).
Species Observation: Species Looked For
Did you find it?: 
I think I found it
Scientific name:
Adelges tsugae
Common name:
Hemlock wooly adelgid
Sampling method: 
Photo of our sampling method.
Place Studied
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N 43.973638 °
W -69.681494 °
Observation Site Information
A photo of our study site.
Upland - Forest
Trip Information
Cushman Mountain
Trip date: 
Mon, 2013-09-23 16:00
Town or city: 
Type of investigation: 
Species Survey


I should note that HWA was first detected at this site doing a random walk through the parcel in 2011. At that point, fewer than 1% of the reachable branches had detectable HWA.