Like I said, Hemlocks are prone to wooly adelgid infestation.
Infestation generally always follows stree and unhealthy trees. The
OP didn't ask for a course in Hemlocks. The question which was
answered was answered out of my own mind, not out of a book I worship.

No a worshipped book but a published peer reviewed and published data. Show
me your data not your thoughts.


--
Sincerely,
John A. Keslick, Jr.
Consulting Tree Biologist
http://home.ccil.org/~treeman
and www.treedictionary.com
Beware of so-called tree experts who do not understand tree biology.
Storms, fires, floods, earthquakes, and volcanic eruptions keep reminding us
that we are not the boss.
Some people will buy products they do not understand and not buy books that
will give them understanding.