bare wire is better  the more wire and ground the better
it jus thaw to be number 6 minimum size  you could even use copper water pipe if you wanted :) you want as much conductivity, and in fact you do not want to use insulated wire, you want it to conduct to ground which is the point of the ground in then first place being int heh ground
On Apr 16, 2013, at 8:48 AM, Tom Brennan <[log in to unmask]> wrote:

> Howard, my concern was about having the ground wire actually in the ground for
> all that length.  It would require my using an insulated wire and I had read
> somewhere that you can't do that for grounding.  Is that not the case?
> 
> There is grass all the way to the place I'd have to use but since they want the
> wire two or three inches deep and also want me to relandscape the area that I
> dig I guess I'm a little iffie about it <g>.
> 
> Tom
> 
> 
> Tom Brennan  KD5VIJ, CCC-A/SLP
> web page http://titan.sfasu.edu/~g_brennantg/sonicpage.html