Chris Hogg wrote:

What is the best way to stop wooden fence posts rotting below ground
level? My understanding is that keeping them out of contact with the
soil helps considerably (i.e. by setting them in concrete), but would
wrapping the bases in polythene make things better or worse (allowing
for some drainage at the base to let water out)?

As others have said, there's a problem at the concrete/wood interface.
When our last fence died (snapped at the point that the wood entered the
concrete, despite the raised collar, the fencing person recommended
concrete stubs(or similar term). The stubs are buried in the ground to
the recommended depth, and the fence posts are bolted to the stubs with
the base of the post just above the soil. It's not as obtrusive as I
feared, and the fence has withstood some fairly strong winds since, but
my conscience twinges when I remember that concrete is extremely
environmentally unsound. If yours doesn't, you could go for full size
concrete posts to which fence panels/rails/whatever are bolted.

regards
sarah



--
Waist deep, neck deep
We'll be drowning before too long
We're neck deep in the Big Muddy
And the damned fools keep yelling to push on