I have a 7' strip in front of my house at the top of a stone wall that I would like to plant something that would grow:

* Tall enough to serve as a dirt/noise/privacy barrier

* Robust enough to handle periodic doses of road salt

* Grow to a finite width so I don't have to worry about trimming the side that faces the road in years to come (trimming on the house side, although not desired, would be tolerated if I had to plant in a way that gave me more room on the road side).

* Something that would keep its green all year, so it would have the same function during the winter as it does the rest of the year (we live in Northeastern PA).

* Have a taproot, so my wall doesn't get damaged as the plants grow.

I was thinking about green giant cedars, but was fearful that they would get too big to serve my purpose.

Any suggestions? We are novices, but do have some experience, so any assistance would be greatly appreciated.

Thank You