Recarbonize the world
Exploring Biochar for carbon sequestration

Surplus Timber

Aversley wood owned by the Woodland Trust was being treated as though it was high forest even though it is in fact derelict coppice. The wood is mainly Ash, Oak and Hazel. Management of the wood has been minimal for many years with little more than keeping the rides open. Recently this has changed with the advent of Ash Dieback and high winter winds. A lot of overgrown coppice stools and poor quality and dead timber was toppled by the gales. In an effort to make the wood safer to walk through, the Trust has felled many trees along rides in the western half of the wood. Since the ground was far too wet to bring in heavy lifting equipment, they decided to fell and leave collecting of the timber until the ground is dry enough to support tractors and the like. This decision is to be applauded because machinery can destroy paths and rides in the winter. In days gone by contractors would have waited for a hard frost to retrieve the timber they had felled. Due to global warming this is no longer practical. We have had fewer than half a dozen slight frosts and high rainfall this winter giving no chance of timber retrieval.

While walking through the wood and looking at the lying timber, I was struck by how much of it was rotten, misshapen and poor quality. Some of this due to disease but most down to lack of coppicing and management. As an avid greenwood turner, I tend to look at an Ash tree in terms of how many chair legs it might yield. It has to be said that very little would be useable from these poor specimens. I realise the people doing the felling are under pressure to get trees felled but they have put no protection around the stumps and stools of the trees they have felled. The herd of deer living in the wood will eat off any regrowth from the stools and stumps. This will prevent the wood from regenerating into a healthy state. One simple form of protection would be to cover the stools with brash from the tops of the trees. Once the stools have sprouted, the brash protects the new tasty leaves the deer eat. In a couple of years the new stems will be out of reach and the brash will have broken down to a mulch around the base of the coppice.

What to do with the lying timber? The government is moving to reduce the use of log fires in homes. So firewood is not the answer but the timber is not fit for much else.

One thing it could be used for is making biochar/charcoal. Taking a portable retort charcoal kiln into the wood during the summer. Pyrolysis would reduce the mass that would have to be carted by around 50%. The operation of the retort would be seen by the local population who could be educated in the use of biochar. Given the area is largely heavy clay on the edge of the fenlands, sale of the biochar to be used as a soil improver might find a ready market. Biochar tends to be alkaline and therefore works well with heavy clay that tends to be acid. It improves drainage, it filters and traps fertilisers that would otherwise be washed away in the run-off into streams. Once people realise that biochar is a workable form of permanent carbon capture as well as a soil improver the demand for more will revitalise the woodland and provide an income to support the woodland management.