Our leyland cypress were at least 7 to 8 years old, quite tall and growing
in the back of the yard (in zone7, North Carolina.) and were watered by my
husband when nec., the rain, a sprinkler system which came to about 10 feet
from them.
Over a period of about 3 years the east side of the plants began turning
brown and getting bare.

The species is known to be prone to diseases. Take a look at
this page:

http://www.ces.ncsu.edu/depts/pp/not...din17/od17.htm


Mike Prager
On the North Carolina coast - Zone 8a
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