I'm fencing 10 acs. Except for a few left over pressure treated posts, I'm using locust and cedar that I've cut off our place. All the posts are 3' deep. Corner posts are 7' apart. Using some some old well casing for corner brace poles. Drill a 1/2" hole thru the corner posts and drive a 12" piece of rebar to hold the 4" pipe in place, then double wire to tighten. The line posts are 15' apart. I'm going to use 48" woven wire, with 1 run of smooth wire 4" above the woven. The ground is starting to freeze, so I may not be drilling to many more holes, but I'll cut more posts.