I decided to bury the antenna just deep enough to avoid the mower, but not too deep as to affect reception. I bought some new RG6 coax, heavier gauge enameled copper wire, Channel Master balun and a saw-tooth border edger to slice open 120 feet of lawn.
It took about an hour to slice the lawn and another hour to put down the copper wire generously using lawn staples to keep the wire below ground level. By the way, the stainless steel lawn staples seem to have no effect on the operation of the antenna. Another by the way, I turned the new antenna about 30° counter-clockwise compared to the old LoGs so that its axes now lie 0°/180° and 90°/270°.
After connecting the balun and coax and running the coax up to the shack, I anxiously turned on the IC-R8600 and I was very disappointed. All signals were weak. There were no signals on frequencies that I normally hear signals and 1600 to 1710 kHz was totally dead. [There is a Department of Transportation Travelers Information Station (DOT TIS) 3 miles away on 1670 that blasts in here normally and there was nothing to hear on 1670 with the new antenna.]
I thought maybe the antenna being sunk in the ground was the cause even though at the most, the antenna was only a half-inch below the surface. So I went out and lifted the whole antenna out of the ground and returned to the radio, but it did not make any difference.
My next guess was that the new balun might be the culprit, so I swapped it for the old balun and 1600 to 1710 kHz came back to life, but all the signals were still weak or non-existent. That left the coax and the copper wire as culprits. Except for a break in the enameled copper wire, I could not figure out how the wire could be bad. That left the coax, so I replaced the new RG6 coax with the old RG59 and that solved the problem. Bad RG6!
I pushed the copper back down into the ground and the signal levels were exactly the same with the antenna on top of the lawn and with the antenna underground by 1/4 inch to 1/2 inch depth.
Next day, I cut the lawn and the antenna survived.