A benchmark in this technology is Polyphaser. These
application note applies to your questions:
http://www.polyphaser.com/ppc_PEN1002.asp
http://www.polyphaser.com/ppc_PEN1024.asp
http://www.polyphaser.com/ppc_PEN1026.asp
http://www.polyphaser.com/ppc_PEN1025.asp
http://www.polyphaser.com/ppc_PEN1003.asp

wrote:
That's a slick idea, we're sandy loam and clay around here. Next
time I sink a ground rod I'll remember the water.