Bog-wood, also known as morta is wood from trees that have been buried in peat bogs and preserved from decay by the acidic and anaerobic bog conditions, sometimes for hundreds or even thousands of years. The wood is usually stained brown by tannins dissolved in the acidic water. Bog-wood represents the early stages in the fossilisation of wood, with further stages ultimately forming lignite and coal over a period of many millions of years. Bog-wood may come from any tree species naturally growing near or in bogs, including oak (Quercus – "bog oak"), pine (Pinus), yew (Taxus), swamp cypress (Taxodium) and kauri (Agathis). Bog-wood is often removed from fields etc. and placed in clearance cairns. It is a rare form of timber that is "comparable to some of the world's most expensive tropical hardwoods"
Because bog-wood can remain undecayed for thousands of years it is of use in dendrochronology, often providing records much older than living trees. Wooden artefacts lost or buried in bogs become preserved as bog-wood, and are important in archaeology.
Bog-wood may be used in joinery to make furniture or wood carving. Bog-wood sometimes has aesthetically interesting shapes (similar to driftwood) and as such may be use as ornaments. As bog-wood dries out, it may crack or split, but this does not necessarily detract from the aesthetic qualities of a bog-wood sculpture. It is a traditionally favoured wood for the carving of dirks (bìodagan) and sgian-dubh in the Scottish Highlands due to its natural colour. It is also used to make tobacco pipes.
Bog-wood is used in aquaria for ornaments, providing hiding places for fish and a growing surface for plants such as Java fern. Additionally, the leaching of organic compounds such as tannins into the water causes a brown colouration. It is also a staple part of the diet for Pleco, Ancistrus and Panaque catfish as it aids digestion.
During the nineteenth century bog oak was used to make carved decorative items such as jewellery.
See also 
- Aquarium substrates
- Mopane wood, recovered from deserts and often sold as an alternative to bogwood for aquaria; it is sometimes incorrectly labelled as bogwood or charred bogwood.
- Sweet Track, a timber causeway in Somerset, England, its timbers preserved in waterlogged ground for over 5,800 years.
|Wikimedia Commons has media related to: Bog-wood|
- Information and pictures on Bog Oak in natural form as well as finished artworks.
- Image of 5000 year old bogwood recovered from an Irish bog as well as other bog images
- Irish Peatland Conservation Council - Information sheet on bogwood and its formation in Irish peat bogs.