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How much land for firewood?

                              


Joined: Aug 11, 2011
Posts: 44
We're searching for just the right land for our homestead, and one of our concerns is firewood.  We're planning to be off-grid, with our primary heat source and cooking metho being a wood burning stove.  The house (which will be in NY state) will be small (in the 700sqf range), and we'll insulate as best we can.  So we'll go through, say, 6 cords of wood each year?  Maybe a bit more?  How many acres of wooded land do we really need if we're managing the majority of it as a woodlot for firewood, and want it to be fully sustainable?
Sam White


Joined: Mar 08, 2011
Posts: 211
Location: Caerphilly, Wales, UK
    
    1
If you're wanting to provide your own firewood on a fairly small parcel of land, coppicing will be the best way to ensure that you have a sustainable source of firewood. My dad recons that 3 acres would be enough for a family of four although he's no expert and it will obviously depend on your climate and how well your house is insulated. You should be able to make some rough calculations about how much wood you would have to burn in a year to provide for all your needs... I can't point you anywhere specific but I imagine Google would help.

Most types of broadleaf tree coppice although their growth rates are obviously different (climate plays a role in growth as well). Determining which species to plant will be based partially on growth as you will want the trees coppicThe Woodland Wayed first to be ready for recoppicing the year after your final cant has been cut.

I recommend The Woodland Way by Ben Law if you wish to read more on the subject of sustainable woodland management and coppicing (albiet in the context of the UK... An american member might be able to recommend a similar book for the US market).


"A society grows great when old men plant trees whose shade they know they shall never sit in."
            


Joined: Jun 27, 2010
Posts: 75
Location: Ontario, Canada (44.265475, -77.960029)
Plant 600 trees in a grid 8 by 8 feet. After 2 years you cut the 120 trees closest to the south. This wood will be about 2" in diameter, good for kindling. Doing this will give extra sun light to the trees behind them. Next year (year 3) you cut the next 120 trees behind them. Year 4 you continue cutting your way back. By now you are cutting trees that are about 4 to 5 inches in diameter. Year 5 you have only 120 original trees left. They are 6 inches in diameter which means, no splitting. Cut them down and use them. You should get enough wood from those 120 trees to heat your house that winter.

Up to this point, you have been increasing the amount of wood you cut every year. You would say, now what?

Year 6 you will be cutting down the first lot of 120 trees you cut 5 years ago. They regenerate! Those trees you cut on year 6 will also be 6 inches in diameter. Year after year you will be cutting 120 trees that are 6 inches in diameter. Life expectancy of a poplar is 40 years.

Do you think your trees are getting old? Use some of the cuttings you get every year (you get thousands) to plant new trees.

You have heard that poplars do not give you the BTU that other woods do. That is correct, hybrid poplars will give you about .6 of the energy you can get from hard woods, such as hickory or maple but this shortcoming is offset by the amount of wood these trees generate.


black locust would give you more BTU's and are fast growing, nitrogen fixers.

Regards,
Mike


Anyone who believes exponential growth can go on forever in a finite world is either a madman or an economist.
Tyler Ludens
pollinator

Joined: Jun 25, 2010
Posts: 5326
Location: Central Texas USA Latitude 30 Zone 8
    
  20
I hope you'll look into passive solar heating as well as insulation.  This will help keep your firewood needs to a minimum.  A book I love about passive solar housing and food =-growing for northern climates is "Solviva" by Anna Edey.  Lots of inspiring ideas in it: http://www.solviva.com/solviva_book.htm

Here's a chart of trees and their btus:  http://www.chimneysweeponline.com/howood.htm

Personally I would try to plant American Persimmon which has very high btus per cord plus produces food if you're in southern NY.  Northern NY is out of the native range of American Persimmon.  http://www.treetrail.net/diospyros.html ; White Oak is also a good choice.  http://www.chimneysweeponline.com/howood.htm


Idle dreamer

Sam White


Joined: Mar 08, 2011
Posts: 211
Location: Caerphilly, Wales, UK
    
    1
MikeH wrote: Life expectancy of a poplar is 40 years.


I can't speak specifically for Poplars but coppicing can extend the lifespan of many species almost indefinitely (assuming that they are kept in rotation).
            


Joined: Jun 27, 2010
Posts: 75
Location: Ontario, Canada (44.265475, -77.960029)
H Ludi Tyler wrote:
Personally I would try to plant American Persimmon which has very high btus per cord plus produces food if you're in southern NY.  Northern NY is out of the native range of American Persimmon.  http://www.treetrail.net/diospyros.html  White Oak is also a good choice.  http://www.chimneysweeponline.com/howood.htm


I would plant them as well but not for firewood or coppicing because of the slow growth rate.  It would seem to me that hybrid poplars and/or black locust make sense if you need a quick and renewable source of firewood.  The lower BTU's of the poplars are offset by their very rapid growth. Propagation of both is very easy so you can compensate for short life and any tendency to windstorm damage.  I have some hybrid poplars that I planted in the fall of 2007 after they were dormant.  They have never been watered and have had to compete with very vigorous surrounding "weeds".  Last year they showed some noticeable growth; this year they have exploded.  They have progressed from about 8' whips about 1" in diameter to +16' trees that are around 4" in diameter.  Given a bit of care,  they probably would have done much better.  It's a bit early but I will coppice the largest of them this fall after dormancy just to see what happens.

I'm quite impressed with the growth rate of the black locusts that I started from seed in May.  They are now 4' tall.  I expect that my bees will be even more impressed when they flower.



  • [li]Black Locust: A Multi-purpose Tree Species for Temperate Climates[/li]
    [li]Black Locust: An Excellent Fiber Crop[/li]
    [li]James A. Duke. 1983. Handbook of Energy Crops. unpublished. [/li]
    [li]Black Locust[/li]



  • Fred Morgan
    steward

    Joined: Sep 29, 2009
    Posts: 973
    Location: Northern Zone, Costa Rica - 200 to 300 meters Tropical Humid Rainforest
        
      12
    I have often heard that 2 cords (that would be full cords) per acre is sustainable.  So, if you need six, you need no less than 3 acres, and you should double that, since you sure don't want to run out.

    Besides, inside the 3 acres, you can't expect all to be the same. Beware the "sharp pencil" syndrome where you add everything up, and don't leave yourself a lot of fudge factor.


    Sustainable Plantations and Agroforestry in Costa Rica
                                                


    Joined: Nov 09, 2011
    Posts: 4
    Two or three acres, managed well, should be plenty for a small home for many, many, years.

    If you have 13 acres, all forest but for one acre, you need not worry. We have 14 acres. I cleared out two acres, and have been burning that wood as our sole source of heat for almost six years. I have wood rotting because I cant use it.

    I gave away some too. And I built a small log cabin with some of those trees. I've never had to cut down a tree just because I needed firewood.
                                  


    Joined: Jun 27, 2011
    Posts: 8
    What about Bamboo? It grows fast and densly, but i've heard very hot and quickly...
    i found these quotes:

    "Bamboo, when used as fire wood, produces more btu per weight than hardwood and makes less ash. "

    "Bamboo charcoal will maintain a constant heat longer than hardwood charcoal."

    What does everyone think?
    Philip Freddolino


    Joined: Jun 02, 2010
    Posts: 53
    We have a 1000 sf. house in N. Idaho and we use 2-2 1/2 cords for heating. Not sure how much more wood it would take to cook.
    Ken Peavey
    steward

    Joined: Dec 21, 2009
    Posts: 2475
    Location: FL
        
      79
    I've seen 1/2 cord per acre per year being a sustainable harvest rate. Fred Morgan stated 2 cords/acre. This makes the ballpark 3-12 acres of woods. There would be factors which would affect woodland production: water, soil quality, temperature, as well as the method of harvest.

    Giving priority during construction to reducing the demand for fuel will save you the most work later on. I've lived in NY for a few years, the winters can get cold, especially in January. Insulation, and in no small amount will keep you toasty. 700 sqft is a cozy space, but when its 20 below with a howling wind, sometimes the wood just wont burn fast enough. Rooms that can be closed off, porches that can be enclosed, limited north facing windows, small windows, windows that can be blocked off, thick exterior walls, all this helps. Plumbing in or near the core of the structure should not be overlooked. Outside windbreaks help-a treeline, barn, or the stacks of firewood. And don't forget to pile the snow around the house for a little extra boost.

    Alternative fuels are available in the woods. Leaves can be compacted into briquettes. While they don't offer as much heat as the same volume of wood, leaves come back in a year. If you are near a town of any size, people will gather up all the leaves you need, fill handy trash bags and put them by the side of the road for you. This would be a good fuel for starting fires and cooking in the summer, but it wont last all night. Gather all those leaf bags you can, pile them up against the house. If you run low on logs it would be towards the end of the cold season. You'd have the leaves at the ready at least, and you can always compost them.

    Bamboo
    I've burned the bamboo from my yard. It burns hot and fast. A person would be hard pressed to keep a stove full. The bamboo I have is hollow. When it burns, it explodes. Not like TNT, but it makes a hell of a POP and can send material flying a few feet. This popping can be avoided by crushing the bamboo before burning.


    Seed the Mind, Harvest Ideas.
    http://farmwhisperer.com
    Ian Rice


    Joined: May 03, 2011
    Posts: 12
    Regarding Bamboo as fuel again. What about splitting it to avoid the TNT reaction when burned? More importantly though, has anyone got any experience using bamboo as a fuel for a rocket stove? Since it burns so hot and results in so little ash, wouldn't it be a PERFECT solution for a Rocket Mass Stove? Thoughts?
    Ken Peavey
    steward

    Joined: Dec 21, 2009
    Posts: 2475
    Location: FL
        
      79
    The bamboo I have is hollow and sectioned. About every foot the tube is closed off. The pop results from hot gas within the section building enough pressure to burst the bamboo. If it was cut through each hollow section it would allow the hot gasses to escape, eliminating the pop.
    Ian Rice


    Joined: May 03, 2011
    Posts: 12
    Yea, that's what I thought! I'm growing Japanese Arrow Bamboo, very easy to lop into lengths and you can split the lengths in half with ease.....it ought to eliminate the popping!
    Ken Peavey
    steward

    Joined: Dec 21, 2009
    Posts: 2475
    Location: FL
        
      79
    I've never identified the cultivar I have, googled the arrow bamboo. It is consistent with what I have. Thanks.
    Mike Dayton


    Joined: Dec 15, 2010
    Posts: 149
    Location: sw pa zone 5
    I have always heard that 10 acres of wood lot properly managed will provide all of a familys needs forever. That includeds housing, furniture, heating and cooking. That number seems right to me here in SW Pa, I think NY state would be about the same. I agree with what some of the people befor me have said, you might be able to get by with less land intensly farmed for wood, but if you just want the land to be woods, naturally regenerating 10 acres would seem to be a good safe number. It all depends on how safe you want to be in planning your future. Good luck with finding your dream homestead property.


    Never doubt that a small group of dedicated people can change the world,  Indeed it is the only thing that ever has. Formerly pa_friendly_guy_here
    John Johnson


    Joined: Dec 12, 2011
    Posts: 1
    Location: Arkansas
    Thanks to everyone commenting in this thread! My family and I are in the process of establishing a farm on a mostly clear cut, poorly drained five acres in western Arkansas. We have a lot of challenges to overcome and given the small size of our property and the relative lack of trees, I was almost certain that sustaining adequate wood supply would be impossible. That is, until I read Mike's comments about the qualities of black locust. Now I've done a 180 from my wood shortage despair.

    By far, the most prevalent tree we do have on the property is honey locust. Being annoyed by their uncontrollable growth and dangerously long thorns, I was getting ready to cut all of the younger ones down to keep them from proliferating further and to make room for nursery purchased shade and fruit trees. Now knowing about their remarkable versatility and usefulness, I plan to harvest the pods in May and seed them around the pond berms and in a few clusters throughout my pasture. With luck, they'll be large enough for harvest/coppice and seasoning in 4-5 years and can provide us with a sustainable wood source thereafter. We might even try to make some beer from the sweet seed pods.

    Does 4-5 years seem like a reasonable time frame for locust to reach a good diameter for burning? I think we can make the dead wood we cut and split in the initial cleanup of the property last for 2 years. Years 3-5 will require wood to be brought in from my parents' lot until ours is seasoned and ready to go.
    S. G. Botsford


    Joined: Oct 23, 2011
    Posts: 62
        
        1
    If you are managing land for firewood then 2 cords/acre is pushing it, but depending on your climate may be doable. You are, however, pulling most of the surplus biomass out of the forest each year. (1 cord is about 1 ton dry weight. 2 tons dry weight is pretty good for any crop.) If you want to manage your forest for multiple purposes, you need to scale back on firewood.

    I've got 80 acres total, about 15 in mixed poplar,birch, spruce, willow patches. I cut 6 cords a year, and I figure that this is about what I can do without deliberate management. But:

    * I leave half the windfall for the fungi and the bugs. That in turn supports a whole crop of birds.
    * I thin the edges of the poplar patches from the 1 per square foot to 1 per 6x6 space more or less. The small trees are too aggravating to cut up, so they get stacked out of the way and allowed to rot. Stacking them slows down the rotting process, but gives cover for small critters.
    * Most of my wood harvest is poplar, done in patches about 150 feet across. A clearing this large will grow back. Smaller than that is too shaded.

    Poplar is not the best wood in terms of heat per cord, but it is the best for heat per hour of my time. Birch has to be split or it rots before it dries. Willow is too small. Spruce has to be limbed, and I get sharp needles in enerything. So most years I end up with 5 cords of poplar a cord of spruce, and a bit of whatever else got in my way.

    As I said, this is pushing my land. So when I can I get permission to harvest elsewhere. Or people will drop off pallets. Pallets are quick to cut up with a chainsaw. Cut the slats on either side of the spacers, leaving a chunk of slat on the spacer. Cut the spacers between the slats. The nails will be in the ashes. Either discard the ashes, or separate the nails out with a magnet. Otherwise you find them with your tires.
    Cj Verde
    pollinator

    Joined: Oct 18, 2011
    Posts: 3237
    Location: Vermont, off grid for 22 years!
        
      54
    Wild Irish Rose wrote:The house (which will be in NY state) will be small (in the 700sqf range), and we'll insulate as best we can.  So we'll go through, say, 6 cords of wood each year?  Maybe a bit more?  How many acres of wooded land do we really need if we're managing the majority of it as a woodlot for firewood, and want it to be fully sustainable?


    I live in Vermont. My house is 2400 sqf and we burn between 2 - 2 1/2 cords (depends on the wood & the weather). The house is R38 on six sides. It was designed & built by a firm near Saratoga, I think, that designs "Low Energy Requirement Homes."

    It is currently 73° near the woodstove, probably warmer upstairs. It is 1° outside. In the morning it might be 65° downstairs but it only takes an hour to get back to 70°.

    It shouldn't take much NY land to keep a 700 sqf house warm sustainably.


    My project thread
    Agriculture collects solar energy two-dimensionally; but silviculture collects it three dimensionally.
    Cj Verde
    pollinator

    Joined: Oct 18, 2011
    Posts: 3237
    Location: Vermont, off grid for 22 years!
        
      54
    John Johnson wrote:That is, until I read Mike's comments about the qualities of black locust. Now I've done a 180 from my wood shortage despair.


    There is a draw back to black locust. It is hard. Very, very, hard. We got some for free and sparks started flying when hubby used a chainsaw. Talk to someone who has actually used it for burning. It may burn too hot.
    Jonathan Byron


    Joined: Apr 16, 2011
    Posts: 225
        
        1
    Taylor Hatfield wrote:
    "Bamboo, when used as fire wood, produces more btu per weight than hardwood and makes less ash. "


    Bamboo is high in silica, and this not only leaves 'ash' - but this ash can fuse together into clumps and this makes bamboo chips a poor choice for automated stoves and furnaces as they are usually designed. But if the bamboo is suited to a site, the per acre productivity can be high.
    Greg Hickey


    Joined: Dec 24, 2011
    Posts: 21
    I am glad there is so much discussion on Bamboo. I think it has been well covered here; but will add from forestry studies Bamboo produces 40 times more mass than timber significantly reducing the acreage needed. Rose, I would also ask you to consider this. What will the purchase price of the land plus taxes run you for the three acres? If you cost it out, you may find it is cheaper to buy your wood than to buy land for the purpose. Of course there is the intangible benefit of self sufficiency which has to be considered.

    I have friends in Northern Maine whom heat exclusively with wood. They run 4-6 cords a year for about the same square footage, depending on the severity of the winter. They have a logging truck bring the trees to them in trunk form; and cut and split themselves. (funny how I always get an invite to visit in the last summer/early fall. ) If I recall they spend about $2000 a year on a load of wood. I believe at that price level there is parity with taxes. Factor in the cost of felling and hauling your logs up to the house, and you might find it cheaper to buy a smaller parcel or put the wood lot into more productive purposes.
    S. G. Botsford


    Joined: Oct 23, 2011
    Posts: 62
        
        1
    I question that 40 times figure. That would be on the order of 80 tons dry weight per acre. That would imply a huge net productivity. I don't think ANY source of photosynthesis can do that. But then I have been wrong before.

    Permeculture is not economical. Almost everything you do in permaculture costs more than doing it at an industrial scale.

    That doesn't mean it's a bad idea. I spend 4 weekends a year harvesting my wood for the winter. I'm pretty laid back in my work habits, so call it 5 hours a day. 40 hours for my wood. That 40 hours when I worked for a living would have been about $1200. By burning wood, I probably lower my heat bill by $75 per month. So I would be better off financially to work an extra week a year.

    But then I would not be out in the woods with my dogs. I wouldn't be aware of new shrubs, new weeds.

    A permie way of life is likely heathier, less boring, more fun, and deeply satisfying. But you have to jump through some interesting hoops to make it a way to life that is financially better than just about anything over minimum wage.

    My opinion: If land is too expensive to have a casual forest that you can glean your winter heat from, then you need to move to where land is cheaper.

    Rule of thumb: People don't like to commute more than an hour. Once you get an hour from the nearest big city, land is far more affordable.
    Greg Hickey


    Joined: Dec 24, 2011
    Posts: 21
    S.G.

    The studies were done for pulp production. I believe the gains come from the ability to harvest every year after the first three years for many years before a timber crop can be harvested. So you are looking at 7 to 17 years (depending on the tree variety) of culm production vs. 1 tree coupled with greater density per acre than trees. Bamboo is in the grass family and from sprout to full height in one year, after the root system is fully established (typically 3 years.)
    S. G. Botsford


    Joined: Oct 23, 2011
    Posts: 62
        
        1
    http://www.inbar.int/publication/txt/INBAR_Working_Paper_No36.htm

    Gives figures of about 10-20 tonnes/hectare (4.5-9 T/acre) annual production.

    This is for sub-tropical to tropical areas. Temperate areas are lower production. I couldn't find good figures on annual production of typical northern temperate forests.
    Greg Hickey


    Joined: Dec 24, 2011
    Posts: 21
    Interesting take on estimating firewood of standing trees per acre from the University of New Hampshire: http://extension.unh.edu/resources/files/Resource001044_Rep1200.pdf

    S. G. Botsford


    Joined: Oct 23, 2011
    Posts: 62
        
        1
    It's a BAD way to estimate.

    1. No values for taper. A forest of lodgepole pine is a LOT taller than a forest of balsam poplar.

    2. He has a doubling of trunk diameter giving about a factor of about 4 for the amount of wood. In fact it's closer to 8.

    3. He stops cutting at 4" diameter. I stop at 2.5" (Can't have too much kitchen wood...)

    4. If his example patch is representative, he's in a really sparse forest. A patch that size should have 40 5" trees or a good dozen 12" trees.

    A better, quicker way to take a survey:

    http://en.wikipedia.org/wiki/Wedge_prism

    You don't get an itemized inventory out of this, but rather the accumulated area of all the stumps. From that, an estimate of the height, and tables you can look up the volume. If you can count to 100 you can use a wedge.
    Guy De Pompignac


    Joined: Nov 16, 2010
    Posts: 190
    Location: SW of France
    Sam White wrote:
    I recommend The Woodland Way by Ben Law if you wish to read more on the subject of sustainable woodland management and coppicing (albiet in the context of the UK... An american member might be able to recommend a similar book for the US market).


    I'm european but waiting this book :
    http://www.coppiceagroforestry.com
    Guy De Pompignac


    Joined: Nov 16, 2010
    Posts: 190
    Location: SW of France
    http://www.nativeforestry.co.uk/firewood.html

    A well stocked mixed broadleaved coppice woodland should produce approximately 3 tonnes of air-dried wood per hectare per year.
    An average three bedroomed house would need 7-9 tonnes of air-dried wood to provide all the heating requirements. The area of coppice woodland would need to be at least 3 hectares in order to be self-sufficient in firewood.
    S. G. Botsford


    Joined: Oct 23, 2011
    Posts: 62
        
        1
    Thanks for the figure.

    For our north american readers a hectare is about 2.5 acres. So 3 metric tons per hectare is about 1.25 tons per acre,

    I don't think it has to be even very well managed to do that. I've usually figured a ton per acre from a typical poplar wood with no management at all, but maybe I'm over estimating.

    It is going to be hugely dependent on climate. In western Canada water is the chief limiting factor. We only get 20 inches of rain a year. The poplar grow like weeds until early July when the rains stop. If you hand water them they keep going until August. We also have a short growing season -- last frost in May, first frost in September. I would reckon that Brittain has enough longer growing season that production would be substantially higher there than here.

    Note that you get more biomass from stems -- 1" to 2" diameter trees on 6-12" spacing. But using these for firewood is a pain. If I had to make do with that size wood, I'd cut it down in the spring. let it lie there all summer, and run it through a chipper in the fall, and burn chips. You don't want to chip it when wet, as the stack will heat up.
    Matthew McCoul


    Joined: Jul 03, 2014
    Posts: 14
    Reviving a dead conversation, I know, but for people googling answers to this:

    How much fuel you need to run anything is going to be based on how efficient the thing is.
    Asking how much wood you'll need to heat home is like asking "How much gas will a vehicle need?"

    What kind? A semi truck? A smart car? Does it run an old, wasteful engine? Something newer and better designed?


    When it comes to heating homes instead of running cars, look into all kinds of wood-burning heaters. And all kinds of insulation.
    Not all the common ones are the cheapest, or the best, and you may save yourself a lot of wood and work with the right choices.

    Rocket mass heaters are easy, waste-not, and warm. And there's plenty of discussion on them here at permies - a good place to start.
    Glenn Herbert


    Joined: Mar 04, 2013
    Posts: 210
    Location: Upstate NY, zone 5
        
        6
    They also work best with the small wood you get from coppicing or clearing scrub and deadfall branches. Less work and more efficient use of resources.
    Dale Hodgins
    pollinator

    Joined: Jul 28, 2011
    Posts: 4354
    Location: Victoria British Columbia-Canada
        
      67
    I've determined that the exact amount of land required is --- none at all. Free wood sources abound. I only gather free wood if the quality is excellent. My landscaping and demolition work both give me mountains of wood that I'm paid to remove.

    In a homestead setting, ideally your needs would be supplied by wind fall, forest improvement cutting,road maintenance, orchard maintenance and slabs and slash left over from milling your own lumber.


    Dale's picks - These are some of my favorite threads. Greed - http://www.permies.com/t/10736/md/unbridled-greed-ambition-compatible-permaculture My garden - http://www.permies.com/t/27910/projects/Dale-Day-Garden ethics - http://www.permies.com/t/11534/permaculture/frustration-ethics Good wood bad wood http://www.permies.com/t/12206/hugelkultur/Hugelkultur-Good-wood-Bad-wood Alder - http://www.permies.com/t/10609/plants/Alder-nitrogen-fixation-native-tree Bees - http://www.permies.com/t/10917/bees/time-replace-European-honey-bee Pulling nails - http://www.permies.com/t/10249/natural-building/Removing-nails-recycled-wood-techniques
    Mat Smith


    Joined: Jan 01, 2014
    Posts: 87
    Location: Gold Coast Hinterland QLD, Australia
        
        1
    Dale Hodgins wrote:I've determined that the exact amount of land required is --- none at all. Free wood sources abound. I only gather free wood if the quality is excellent. My landscaping and demolition work both give me mountains of wood that I'm paid to remove.


    I do the same and get free wood from Gumtree (kind of like Craigslist).
    I am in the sub-tropics though, so I don't need all that much for winter.
    Have got some really good hardwood several times
     
     
    subject: How much land for firewood?
     
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