Invasive SpeciesHemlock wooly adelgid

Adelges tsugae
NOT FOUND by astrogirl
ID Confirmed
Quality checked by Dee
Peer reviewed by Dee
Field Notes
It was late in the afternoon when there was still good sun available. Checked the perimeter of the backyard where it meets the more heavily wooded area of the property. There are many hemlock trees in that vicinity. There are some suspicious looking things attached to the hemlock leaves that seems to glue them together, but it does not have the distinctive wooly appearance.
A sketch of our study site.
Supporting Evidence
Photo of my evidence.
The undersides of the hemlock needles were clean of the wooly coverings. The color of the trees was a healthy looking green with very few browned needles.
Photo of my evidence.
I did find some suspicious looking attachments to the needles but they did not have the really distinctive white wooly appearance to indicate that the wooly adelgid was present. The branches displayed healthy growth
Species Observation: Species Looked For
Did you find it?: 
I think I did not find it
Scientific name:
Adelges tsugae
Common name:
Hemlock wooly adelgid
Sampling method: 
Just looking around
Photo of our sampling method.
Place Studied
We’re sorry, JavaScript is required to view the map. If JavaScript is you may wish to upgrade to a newer browser in order to view this map.
Map this species
N 44.222324 °
W -69.124057 °
Observation Site Information
A photo of our study site.
Upland - Developed areas
Trip Information
Edge of woods in backyard
Trip date: 
Tue, 2012-04-03 17:00
Town or city: 
Type of investigation: 
Species Survey


Nice pics good person!

Your sketch was amazing! I could definitely see the white "racing stripes" on the needles.


What do you think the suspicious attachments were?

Nice pictures. There really in focus and I like your photo of suspicious looking attachments ~FM

There are two species of hemlock needleminer recorded in Rose and Lindquist's Insects of Eastern Spruces, Fir and Hemlock, they are the green and brown hemlock needleminers. As you might guess, you can tell them apart by the color of the caterpillar. The caterpillars overwinter, so if you were to pull apart those brown needles/silk pictured above, you could tell which species caused that damage. They are not a significant health problem for the tree. A good description of them can be found in Doug Allen's article in the NY Forest Owner Magazine:

I'm so jealous of your artistic talents! Really nice sketch. I like how your sketch even shows how the needles attach with that little stalk. Nice work.

The hemlock description was very helpful, even though my woods are full of them, it was especially helpful to have that little detail to really make sure.

I had learned to ID hemlock a long time ago, but I had never learned to look that closely at the needle attachment. I think it is cool to learn something new like that. Sounds like you enjoyed looking closely, too.