How long would decking timber last in the soil ??

[spender]

How long would decking timber last in the soil ??

As I have some left over and was going to use some to border me grass with, ie embedding it all in the soil.

[The Medway Handyman]

They reckon tanalizing is good for 30 years. Seal the end grain though.

[Andy Dingley]

Shallow buried as edging, a huge amount would depend on the soil. If it's sandy and drains freely, it'll last forever. Heavy clays, or a waterlogged soil where the top layer is usually wet, might soften within a year.

Most treated softwood isn't great for buried work, as the preservative leaches out under prolonged moisture. The advantage of real Tanalised timber was less to improve absolute resistance and more about avoiding this leach-out, thus keeping any preservative action for longer.

[Tanuki]

If you truly want subterranean woodwork to last, it needs to be pressure- treated with a Boron-based antifungal, and/or impregnated with a range of sadly no-longer-street-legal hydrocarbons. If you have access to it, making up a mix of 50% old sump-oil and

50% kerosene is a good wood-preservative: soak the end-grain of your timber in it for a few weeks before burial.

grass

Pretty good. However the standards for tanalising timber have been changed considerably over the years. They have taken out the arsenic and copper so clearly won't last as long as previously (when if was indestructable.)