At the first post location, dig a straight-sided 10-inch-diameter hole as deep as possible with a shovel. Watch out for wires, pipes drains, and sprinkler lines.
Finish excavating to 32 inches deep with a Gibbs posthole digger, which can maintain a 10-inch hole diameter all the way down.
Use a digging bar to loosen rocks and cut roots; discard any rocks larger than a billiard ball.
Tip: Spread a tarp to catch excavated soil.
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