Hedges: Re: getting the top of the cedar hedge exactly level

This is especially problematic when the hedge I am trimming has not been trimmed in decades. Any sugestions?
Thanks for your advice
Michael

 

Fix a post at each end, and tie a piece of string taut between them, at the same height on each pole. That'll give you a guide line.

Don't cut inside where there is green foliage; if you cut into the interior brown, it won't re-grow.

 

Yes, if you are planning to saw through it several feet below the existing top you will end up with a "dead zone" on top.