Hobbies / Books   (Gardening, walking, books, films, theatre etc.)

Peter, Wood posts in the ground usually rot at ground level.

If, at slightly above this level, you auger out a down-sloping hole, about 18mm dia, and make a wood plug to fit. you have a chamber in which you can places preservative to protect at this point.

If you are growing foodstuffs, Beeswax, raw linseed oil and turpentine (genuine, that is) makes a foodsafe preservative.