Saving Water with Wood

[Two_Sheds]

According to my permaculture book Gaia's Garden by J.Todd, the best way to conserve water is in the ground. So, I am burying my rotting wood on my allotment instead of burning it. Apparently it will act like a sponge, soaking up rainwater and holding it in the soil. I already do this with shredded newspaper, so its a logical step forward.
Anyone else tried it?

[Jardiniere]

have not tried this but have lots of rotting wood - how long does this work for? How long is the sponge effect?

[sewer rat]

Haven't tried it but during my 4 years as a pipelayer, laying filed drains, came across lots of wooden posts, old strainers etc that had been buried - they were all saturated so rotting wood definitely holds water - the problem as I see it is will it release it ? From what I have seen the answer is no, or if it does, it does it very very slowly over a lot of years. In the meantime, it will be sucking more and more water out of your soil / subsoil until it reaches saturation point.

[Mrs Dobby]

I'd also be wary of what the wood may have been treated with, older tannalised wood contains arsenic, there was a threead about it a while ago, so having the wood rot down and release arsenic and other nasties into your soil may not be the best thing for your plants, or you come to think about it!