Good question I do not have the answer. It is often the salt spray in the
air that does the harm.
Tree near fast moving cars would have more mist in the air.

Sincerely,
John A. Keslick, Jr.
Arborist
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.



"socram" wrote in message
ups.com...
I originally was going to put in a line of Arborvitae pyramidalis
(emerald green) along the east side of our church, but some more
research showed that the salt from the parking lot could make this a
poor choice. Can anyone point me to a shrub similar is shape
(upright, 3-4 ft diameter, good for a hedge perhaps eventually) that
is more salt tolerant? We're in MI, zone 6.

Thank you!
marcos