Susan wrote:
On 6/27/2010 11:29 AM, Phisherman wrote:

All the pruned arborvitae I have seen do not look good at all,
sometimes get worse the following years. Your landscaper is giving
you very good advice.

I have a large emerald arborvitae that my landscaper trims the
width/girth of, though not the height, to keep it in bounds where it's
hiding an unsightly meter on the front of my house. It's robustly
healthy and full, even after having been sheared into a too narrow cone
shape last year.

I think cutting the top a bit and shearing the width each year should be
tried so as to preserve them if possible. If they get enough sun, new
growth will sprout quickly anywhere they look thin or less filled out.

Shearing is a lot different from topping. Most conifers respond
positively to shearing but few react well to topping. There are many
varieties of arborvitae, had the OP submitted a photo that would help
immeasurably to advise. Topping most of an older tall variety would
result in many years of looking at a stumpy bush... will likely slowly
die from not being able to heal so large a wound, would lose strength
and be prone to disease and insect attack. I would remove it and
plant something more suitable for the space alloted.

http://www.evergreenplantnursery.com...-Thuja-s/1.htm