Post by cannyfradock on Dec 19, 2012 11:58:34 GMT
Courtesy of the Arboricultural Imformation Echange
www.aie.org.uk
The AIE Firewood Burning Guide
A rough guide to wood burning quality.
The quality of the following firewood is based upon various characteristics such as its speed of burn, heat given off, tendency to spark (spit), ease of splitting, time required to season, etc
Grade: 1 = Poor. Grade: 2 = Low. Grade: 3 = Good. Grade: 4 = High.
Alder (Alnus) - A lower quality firewood. Grade: 1-2
Apple (Malus) - Needs to be seasoned well. Burns well with a pleasant smell and without sparking/spitting. Grade: 3
Ash (Fraxinus) - Considered to be one of the best woods for firewood. It has a low water content (approx. 50%) and can be split very easily with an axe. It can be burned green but like all wood is best when seasoned. Burns at a steady rate and not too fast. Grade: 4
Beech (Fagus) - Beech has a high water content (approx. 90%) so only burns well when seasoned well. Not as good as Oak. Grade: 3
Birch (Betula) - Birch is an excellent firewood and will burn unseasoned. However, it does burn very fast so is best mixed with slower burning wood such as Elm or Oak. Grade: 3-4
Cedar (Cedrus) - A good firewood which burns well with a pleasant smell. Gives off a good, lasting heat. Doesn't spit too much and small pieces can be burned unseasoned. I recently burned a large quantity of unseasoned 'Cedrus atlantica' on my narrow-boat. It needed help from a little coal and kindling to get going but once burning was quite good, with little spitting, a very good heat and a wonderful aroma from the chimney. It also split fairly easily. Grade: 2-3
Cherry (Prunus) - Needs to be seasoned well. Burns well with a pleasant smell and without spitting. Grade: 2-3
Elm (Ulmus) - A good firewood but due to its high water content of approximately 140% (more water than wood!) it must be seasoned very well. It may need assistance from another faster burning wood such as Birch to keep it burning well. However it gives off a good, lasting heat and burns very slowly. Dutch Elm Disease is producing a constant & plentiful supply of small dead hedgerow Elm trees of a small diameter. Larger pieces of wood will prove difficult to split. Grade: 2-3
Eucalyptus (Eucalyptus) - Allow to season well since the wood is very wet (sappy) when fresh. Can be difficult to split due to stringy wood fibre. Best method is to slice into rings and allow to season during the summer, the rings will start to split themselves. Burns fast with a pleasant smell and without spitting. Grade: 2-3
Hawthorn (Crataegus) - Good firewood. Burns well. Grade: 3-4
Hazel (Corylus) - Excellent firewood. Allow to season. Burns fast but without spitting. Grade: 4
Holly (Ilex) - Can be burnt green. A good firewood. Grade: 3
Hornbeam (Carpinus) - Good firewood. Burns well. Grade: 3
Horse Chestnut (Aesculus) - A low quality firewood. Grade: 2
Larch (Larix) - Needs to be seasoned well. Spits excessively while it burns and forms an oily soot within chimneys. Grade: 1
Lime (Tilia) - A low quality firewood. Grade: 2
Mimosa or Silver Wattle (Acacia dealbata ) - To add to your list you could advise that Mimosa burns well and smoothly. It is relativley easy to cut and split and seems to dry out fairly quickly (within about a year for the trunks I harvested of up to 8 inches diameter). Geoffrey Stevens. Grade: 3
Mulberry (Morus) - Hardwood. Haven't tried this myself but am told that it is an excellent fire wood. Grade: 3-4
Oak (Quercus) - One of the best firewoods. When seasoned well, it gives off a good, lasting heat. Burns reasonably slowly. Grade: 4
Pear (Pyrus) - Needs to be seasoned well. Burns well with a pleasant smell and without spitting. Grade: 3
Pine (Pinus) - Needs to be seasoned well. Spits while it burns and forms an oily soot within chimneys. Grade: 1
Plane (Platanus) - A usable firewood. Grade: 3
Poplar (Populus) - Considered a poorer firewood (see comments below). Grade: 1
Rowan (Sorbus) - aucuparia Good firewood. Burns well. Grade: 3
Spruce (Picea) - A low quality firewood. Grade: 2
Sweet Chestnut (Castanea) - Burns when seasoned but spits continuously and excessively. Not for use on an open fire and make sure wood-burning stoves have a good door catch! Grade: 1-2
Sycamore (Acer pseudoplatanus) - Good firewood. Burns well. Grade: 3
Walnut (Juglans) - A low quality firewood. Grade: 2
Wellingtonia (Sequoiadendron) - Poor for use as a firewood. Grade: 1
Willow (Salix) - Willow has a high water content so only burns really well when seasoned well. Grade: 2-3
Yew (Taxus) - A usable firewood. Grade: 2-3
Info
Generally hardwoods are best for open fires because they tend not to spit excessively, however there are exceptions. Conifer wood tends to spit excessively when fresh, so is best used for sealed wood burning stoves, again there are exceptions. Many conifers also cause an oily, sticky 'soot' to form inside the chimney which can increase the risks of chimney fires. Once properly seasoned (see below) conifer wood can be successfully used on the open fire without excessive spitting. Ideally, conifer wood is best mixed with hardwood.
Wood to be seasoned should be cut to length (300mm or 10"-18"), split to size and stacked. The stack should be completely covered on the top to prevent rain wetting the wood but air must be allowed to reach the sides of the stack. Leave to season for at least 1 year (more if possible).
In simple terms, the word 'seasoned' means 'dry' and the term 'green' means 'freshly cut from living tree'.
All wood will, when supported by lots of kindling and/or a good ember base, will burn unseasoned. However, you may find some woods are not worth using in this state due to the length of 'hissing' time (as the water boils from within the wood) before they can burn.
I welcome any further information you may have to offer regarding the burning of wood. If I have made a mistake or perhaps omitted something please send details.
www.aie.org.uk
The AIE Firewood Burning Guide
A rough guide to wood burning quality.
The quality of the following firewood is based upon various characteristics such as its speed of burn, heat given off, tendency to spark (spit), ease of splitting, time required to season, etc
Grade: 1 = Poor. Grade: 2 = Low. Grade: 3 = Good. Grade: 4 = High.
Alder (Alnus) - A lower quality firewood. Grade: 1-2
Apple (Malus) - Needs to be seasoned well. Burns well with a pleasant smell and without sparking/spitting. Grade: 3
Ash (Fraxinus) - Considered to be one of the best woods for firewood. It has a low water content (approx. 50%) and can be split very easily with an axe. It can be burned green but like all wood is best when seasoned. Burns at a steady rate and not too fast. Grade: 4
Beech (Fagus) - Beech has a high water content (approx. 90%) so only burns well when seasoned well. Not as good as Oak. Grade: 3
Birch (Betula) - Birch is an excellent firewood and will burn unseasoned. However, it does burn very fast so is best mixed with slower burning wood such as Elm or Oak. Grade: 3-4
Cedar (Cedrus) - A good firewood which burns well with a pleasant smell. Gives off a good, lasting heat. Doesn't spit too much and small pieces can be burned unseasoned. I recently burned a large quantity of unseasoned 'Cedrus atlantica' on my narrow-boat. It needed help from a little coal and kindling to get going but once burning was quite good, with little spitting, a very good heat and a wonderful aroma from the chimney. It also split fairly easily. Grade: 2-3
Cherry (Prunus) - Needs to be seasoned well. Burns well with a pleasant smell and without spitting. Grade: 2-3
Elm (Ulmus) - A good firewood but due to its high water content of approximately 140% (more water than wood!) it must be seasoned very well. It may need assistance from another faster burning wood such as Birch to keep it burning well. However it gives off a good, lasting heat and burns very slowly. Dutch Elm Disease is producing a constant & plentiful supply of small dead hedgerow Elm trees of a small diameter. Larger pieces of wood will prove difficult to split. Grade: 2-3
Eucalyptus (Eucalyptus) - Allow to season well since the wood is very wet (sappy) when fresh. Can be difficult to split due to stringy wood fibre. Best method is to slice into rings and allow to season during the summer, the rings will start to split themselves. Burns fast with a pleasant smell and without spitting. Grade: 2-3
Hawthorn (Crataegus) - Good firewood. Burns well. Grade: 3-4
Hazel (Corylus) - Excellent firewood. Allow to season. Burns fast but without spitting. Grade: 4
Holly (Ilex) - Can be burnt green. A good firewood. Grade: 3
Hornbeam (Carpinus) - Good firewood. Burns well. Grade: 3
Horse Chestnut (Aesculus) - A low quality firewood. Grade: 2
Larch (Larix) - Needs to be seasoned well. Spits excessively while it burns and forms an oily soot within chimneys. Grade: 1
Lime (Tilia) - A low quality firewood. Grade: 2
Mimosa or Silver Wattle (Acacia dealbata ) - To add to your list you could advise that Mimosa burns well and smoothly. It is relativley easy to cut and split and seems to dry out fairly quickly (within about a year for the trunks I harvested of up to 8 inches diameter). Geoffrey Stevens. Grade: 3
Mulberry (Morus) - Hardwood. Haven't tried this myself but am told that it is an excellent fire wood. Grade: 3-4
Oak (Quercus) - One of the best firewoods. When seasoned well, it gives off a good, lasting heat. Burns reasonably slowly. Grade: 4
Pear (Pyrus) - Needs to be seasoned well. Burns well with a pleasant smell and without spitting. Grade: 3
Pine (Pinus) - Needs to be seasoned well. Spits while it burns and forms an oily soot within chimneys. Grade: 1
Plane (Platanus) - A usable firewood. Grade: 3
Poplar (Populus) - Considered a poorer firewood (see comments below). Grade: 1
Rowan (Sorbus) - aucuparia Good firewood. Burns well. Grade: 3
Spruce (Picea) - A low quality firewood. Grade: 2
Sweet Chestnut (Castanea) - Burns when seasoned but spits continuously and excessively. Not for use on an open fire and make sure wood-burning stoves have a good door catch! Grade: 1-2
Sycamore (Acer pseudoplatanus) - Good firewood. Burns well. Grade: 3
Walnut (Juglans) - A low quality firewood. Grade: 2
Wellingtonia (Sequoiadendron) - Poor for use as a firewood. Grade: 1
Willow (Salix) - Willow has a high water content so only burns really well when seasoned well. Grade: 2-3
Yew (Taxus) - A usable firewood. Grade: 2-3
Info
Generally hardwoods are best for open fires because they tend not to spit excessively, however there are exceptions. Conifer wood tends to spit excessively when fresh, so is best used for sealed wood burning stoves, again there are exceptions. Many conifers also cause an oily, sticky 'soot' to form inside the chimney which can increase the risks of chimney fires. Once properly seasoned (see below) conifer wood can be successfully used on the open fire without excessive spitting. Ideally, conifer wood is best mixed with hardwood.
Wood to be seasoned should be cut to length (300mm or 10"-18"), split to size and stacked. The stack should be completely covered on the top to prevent rain wetting the wood but air must be allowed to reach the sides of the stack. Leave to season for at least 1 year (more if possible).
In simple terms, the word 'seasoned' means 'dry' and the term 'green' means 'freshly cut from living tree'.
All wood will, when supported by lots of kindling and/or a good ember base, will burn unseasoned. However, you may find some woods are not worth using in this state due to the length of 'hissing' time (as the water boils from within the wood) before they can burn.
I welcome any further information you may have to offer regarding the burning of wood. If I have made a mistake or perhaps omitted something please send details.
