Tree bog

A tree bog is a form of outside toilet which has willows, nettles and other nutrient-hungry plants planted around it. The fæces are held in a chamber open to the air which allows it to decompose rapidly, feeding the trees around it. Unlike a conventional compost toilet, a tree bog should never need emptying. Effectively, it is a system for converting human fæces to biomass.

History

The tree bog was invented by Jay Abrahams of Biologic Design in the UK after he observed that the trees around the place where fæces were deposited were particularly vigorous.^{[citation needed]} Tree bogs can be considered examples of permaculture design.

The tree bog is a simple method of composting wastes, and since its introduction in 1995 over 500 tree bogs have been built in Britain.^{[citation needed]} They have been on sites ranging from fruit farms and pick-your-own enterprises, campsites and an angling lake to annual festival sites, remote/low impact dwellings holiday cottages and churches.

The tree bog has attracted the attention of NGOs and aid workers who hope to develop its potential for shanty towns or refugee camps - anywhere that water is scarce and the population pressure on resources is high.^{[citation needed]}

Workings

A tree bog is simply a compost heap whose function has been enhanced by use of moisture/nutrient-hungry trees. They use no water, purify waste as they create willow as a biomass resource, and also contain the organic waste, thus preventing the spread of disease.

A seating platform/cubicle is mounted at least one meter high. The area beneath the seating platform is enclosed by a double-layer of chicken wire - this acts as an effective child proof barrier. It air to circulate through the compost heap.

Sawdust, straw, woodchip, ash or other high carbon matter is used to balance the high nitrogen fæces. One design used Effective Micro-organism bran, which helped keep the tree bog be virtually odour free.

The space between the wire is stuffed with straw which acts as a wick to help sop up excess urine preventing the likelihood of odour problems due to incomplete biological absorption of the nitrogen from the urine. The straw filled wire also enables the pile to be well-aerated whilst acting as a visual screen for the first year’s use.

The structure is surrounded by two closely planted rows of osier or biomass willow cuttings; this living wall of willow can then be woven into a hurdle-like structure and its annual growth can be harvested.

Note

Bog here is a British English slang word for toilet, not to be confused with its other meaning of swampland.

External links

• Build your own Treebog

References

• "Woodland Toilets or Tree Bogs". WoodlandsTV. 15 May, 2009. http://www.woodlands.co.uk/tv/2009/05/woodland-toilets-or-tree-bogs/. Retrieved 23 February 2012.