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What is the best way to grow fuel for an RMH

 
Richard Hauser
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This is both a RMH and a tree growing question, so excuse me if it is filed incorrectly.

RMH are efficient but still need fuel and I am lazy.
To avoid all that annoying sawing and splitting, I would it be possible to cut many .75" sprouts with a clipper, then dry and burn them whole.
With the way RMHs gravity feed, what would the best length and width of fuel be? Could you burn yard long twigs?
I was thinking of doing this with black locust as it is always claimed to grow fast, burn clean, hot and coppices well.
Is there a better choice?
Due to the laziness, I also didn't want to remove the bark. Will this cause a problem for drying?

 
Michael Qulek
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Yah know, my neighbor keeps telling me I should get a wood splitter like his because splitting by hand is just too much work. He however weighs almost 300 lbs, and doesn't even want to get off his ATV when his comes visit, because it's too much effort.

There must be some kind of connection there somewhere. Maybe you should reconsider the amount of work if you look at it from a health perspective.
 
R Scott
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Yes you can. Burning whole sticks is awesomely easy. Pick trees that coppice well like willow or hazel or whatever works for your climate and space.
 
Richard Hauser
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[Michael Qulek] Do you listen to the podcast?
I want to be lazy like Paul, working 20 hours a day but spend it solving the big problems.
"Laziness is the mother of efficiency"
I want to be efficient, but I thought the laziness line was funnier, so more likely to garner a response.

 
Jeff Thorpe
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I've been thinking the same thing. Why go to all the effort of splitting cordwood, drying it and then splitting it into small chunks for use in an RMH? Why not just use stick wood, or Coppicing? I'm planning on planting some fuelwood and pollarding it for use in my soon to be built RMH, I want to try Willow, and Black Locust. Black Locust is very fast growing and has some of the highest energy density for wood. But coppicing willow has been done for thousands of years for basketweaving, furniture making, etc. Willow also has the advantage of growing straight rods that are 6'-10' in a single year. I want to design a feed tube for my RMH that will load 6' rods that will gravity feed into the burn chamber. Why cut, split, stack, re-stack and dry, when you could just cut long thin rods that don't need to be split or cut to length, and will dry in a fraction of the time as cord wood. Here's some relevant links:

http://www.esf.edu/willow/documents/VolkWillowOverview111110.pdf
http://www.doubleawillow.com/publications_fact_sheets.php
http://www.thewillowbank.com/willow.firewood.facts.htm
 
thomas rubino
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Hi All; I have started cutting and burning mountain maple ,also known as vine maple. There is no comparison, hands down burns cleaner and hotter than douglas(red) fir or tamarack. No splitting ,but harder to stack. Most has a dry check to the heart. I am thinking of investing in a small cordless rechargeable chain saw so i can leave my gas hog pickup and chain saw at home and just drive my subaru wagon out in comfort and casually cut what fits in the back while leaving room for huckleberries !
 
Michael Newby
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This is exactly one of the things that Geoff goes over in the online PDC - if you live in a cool temperate climate you can spend a lot of time and energy getting your fuel, or you can do a little planning and have a crop of easily coppiced high energy trees somewhere appropriate on your property.

It might take you a little while to figure out the rotation and final number of trees appropriate for your area/setup but eventually you should be able to rotate through the trees only coming back to the same tree every 2 or 3 years. There's trees that they've been doing this to for hundreds of years that are still going strong
 
Glenn Herbert
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If you are in an area where ash (white ash, or possibly other species) grows, that coppices very well and can give nice thumb-size sticks every few years. Not the densest wood, but smooth thin bark when young, and easy to handle. If you get larger pieces, it splits like a dream, too. From an old folk song about woods: "But Ash logs, smooth and gray, buy them green or old, sir/ and buy up all that come your way, for they're worth their weight in gold, sir."
 
Cj Sloane
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Richard Hauser wrote:
I was thinking of doing this with Black Locust as it is always claimed to grow fast, burn clean, hot and coppices well.
Is there a better choice?
Due to the laziness, I also didn't want to remove the bark. Will this cause a problem for drying?


Lots of hard wood trees coppice well in NJ. Oak & Maple for starters. No need to remove the bark. With coppicing, no splitting is necessary. Just harvest the shoots at the width you want and cut the length to fit your stove.

Oh, and dry for a year.
 
Dorcas Brown
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Late last fall my grandson helped me build a RMH. It is usable even without having the bench completely cobbed [heats up my space but doesn't hold the heat long] He lives more than an hour away so I have been waiting to finish it. I found a friend who will do odd jobs for a couple of hours a week, so I hope to get it finished soon. I started scavenging broken limbs along my roadway.Lots of dried wood! I didn't care what kind as long as it was straight enough to go in my feed hole and not punky rotten. I found I could burn quite long pieces but since my feed tube is only 13"tall I had to be careful that they were not top heavy. Having a stick fall over so its burning end is on the floor is not good!
When a Catalpa was wind damaged this summer I was told that it burns quick and hot. So I've got crookedy sticks in my drying pile. A dead Poplar top fell and so I have pretty straight sticks in my supply for this winter. Wood is wood as long as you already have it.
In my yard I planted some Black Locust that I plan to coppice in 3 or 4 years. I want them to be at about the limit of my strength to use my loppers on. My friend with a chain saw has cut sticks[logs] up to 4" or more into about 3' lengths for me any thing bigger is fodder for Hugel beds. We have added wood of many types from storm damaged limbs. What ever kind you have, use it.With a RMH you burn til your bench is warm in winter or until your space is warm in spring or fall. It is a fun [and lazy] [and frugal] thing to do- to heat with wood that otherwise would be wasted.
 
Tristan Vitali
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Willow, Hazel and Black Locust are all excellent ideas for RMH coppice fuel. I'm not too familiar with the sticks of NJ but if you have yellow birch, american beech and sugar maple available, they're also excellent Here on my little mud pie of a home, we're just in the process of clearing, earthworking and planting our nitrogen fixers (only 1 year in), so we're feeding the RMH the mix of what we're clearing. The property was nearly clear-cut around 7 years ago so there is a TON of saplings - aspen, white and yellow birch, beech and sugar maple everywhere. I'm finding that the beech, sugar maple and birches burn the best as the aspen has a very volatile sap that burns like pine pitch and often causes the wood to go up in flames that shoot out the feed if it's sticking out any. The plan going forward will be to coppice beech, yellow birch and sugar maple in rotations for firewood, as well as the willow, black locust and various N-fixing shrubbery we're planting all over. And FYI, beech coppices like a KING! We have one stump out there cut during the logging that has probably 75+ suckers up to 10ft tall ringing it. Beech, from my understanding, is right up there with the black locust when it comes to burning hot and clean

We do also have this other birch looking shrubby tree that I haven't identified yet (bad with tree identification) - it has dark colored bark and dark green leaves, no wintergreen smell and dries out wrinkled with the bark on. That stuff put on upwards of 15 feet and 5" diameter trunks in the 7 years since the cut, so would be a wonderful fuel except it burns HORRIBLY - smells like kerosene and smokes like crazy...nasty stuff...and it creeps out the feed tube like mad. The other one we avoid is fir - balsam fir is everywhere here but I simply wont burn it anymore. The sap is way too volatile - suitable for kindling only I'd say.

Basically, if it coppices well, try it out, then if it burns like crap, just grow mushrooms on it instead Never a wasted resource I say.

BTW, I've heard oak is a very difficult coppice - probably not the best idea. They take just short of forever to put on any decent size and they definitely don't like to pop back from the stumps after a cut. I'd recommend not cutting down your 6 generation oak tree hoping to get good coppice.

 
Cj Sloane
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Tristan Vitali wrote:
BTW, I've heard oak is a very difficult coppice - probably not the best idea. They take just short of forever to put on any decent size and they definitely don't like to pop back from the stumps after a cut. I'd recommend not cutting down your 6 generation oak tree hoping to get good coppice.


Here's about 2 months after pollarding:
Oak coppice></a>

Looks like just a few years before it'll yield RMH sticks. It's about 8" diameter and had to come down because it was eventually going to block me southern exposure.
 
Tristan Vitali
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Cj Verde wrote:
Tristan Vitali wrote:
BTW, I've heard oak is a very difficult coppice - probably not the best idea. They take just short of forever to put on any decent size and they definitely don't like to pop back from the stumps after a cut. I'd recommend not cutting down your 6 generation oak tree hoping to get good coppice.


Here's about 2 months after pollarding...


Not bad! I had read that ash was pretty poor for coppice/pollard as well but was surprised this year by dozens of 3ft tall suckers from the stumps after I cut the future pasture area over the winter. Just goes to show that boots on the ground experience trumps anything you might have read.
 
Glenn Herbert
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Ash has been well-known for many centuries as a prime coppicing wood. There are (or used to be) ash coppice stools in England that are many (10?) feet across from being continuously coppiced from time immemorial.
 
Melvin Hendrix
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To join the familiar refrain to the initial question, there are many plants that can be grown for use in RHM. Ironwood is a tree with a narrow trunk, similar to honey locust, and the wood burns hot. I prefer shrubs as opposed to trees for ease of coppicing and storage. No expensive equipment required. Harvesting can be accomplished with hand tools with your feet on the ground. Plus, the plants can be grown in zones 1 and 2. Arrowwood viburnum can be pruned back regularly and its branches in a mature plant are 3-4 feet long. Sour cherry has branches 2-6 feet in length and can be pruned a couple of times per season, if berries are not desired. Elderberry grows to enormous heights each year, the stems dry quickly, and produces long reeds 8-10 feet or more that can be chopped up and used for kindling or mixed with sawdust and pelleted. Willow branches come in different diameters, and produce an enormous amount of wood from each plant that is easy to store.
 
Valerie Dawnstar
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I can attest to ash coppicing well, too. I have one growing near my foundation that I have to cut back every year. Just can't seem to kill it but I am only half hearted in my try. Ash is good to focus on in the northeast for another good reason -- the emerald ash borer. We might just want to keep the ash trees small to foil this insect. Stacking functions, eh?
 
Melvin Hendrix
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Great point about ash and the emerald ash borer, Valerie. I have a ton of ash on my property and need to start coppicing some of the trees, instead of treating all of them. This will be a winter project if I can find the right arborist.
 
allen lumley
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Valerie &

Melvin: Interesting idea, It stopped me in my tracks, This is probably worth a Thread all its own. Is this your own hypothesis, or have you some information
that it Could be effective ?

If less than 1/2 the tree was effected it is likely that it could work ! But then there could be 2ndary bacterial and mycolo fugal infections due to
the E. A. B.s puncturing the protective bark layer !?

I have a good Arborist/Nursery man to ask, lets see what we can come up with ! Big AL
 
Melvin Hendrix
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Hi, Big Al. Not having coppiced the trees yet, I am still confident that it works, having coppiced other plants for years. My ash trees are very mature, some more than 50 feet in height, but I'm willing to top them off to obtain the wood and prevent the trees closest to the house from falling on it. The one secondary reaction may be the survival of the pest over winter, but once you start sawing the trunk into manageable sections, you should be able to identify the areas where they are located. The trees are most affected where the larvae reside. Your arborist will be able to identify the entry point by the familiar D shape. If you choose to harvest for logs, then you will need to go over the trees with a fine tooth comb in order to control their development not only in your landscape, but your neighbor's also.

Each year I treat, hundreds of mature borers are forced to evacuate from the trees and are all over the garden, but are not a threat, since they are in the process of dying from the chemical treatment, administered in early spring when the sap starts to rise. They are tiny borers, about 1/8 - 1/4 inch. You probably see them every spring if the EAB is a problem in your area, but they do not look threatening. The treatments have saved the trees, but like many permies, using the chemical is problematic. And, of course, the trees must be treated annually since our state governments have not acted judiciously in introducing the wasp that is a natural enemy of the EAB. EAB further underlines why monoculture in the landscape breeds problems that polyculture, even in an orchard, can help to abate.
 
Valerie Dawnstar
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I, too, will ask around and see if I can get something more specific related to tree size.
 
Victor Johanson
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There is a difference between topping and pollarding. Proper pollarding is initiated when the tree is young and respects the tree's innate defense boundaries; it is a legitimate and longstanding arborist practice which actually extends logevity. Most of what's termed pollarding these days is just whacking the top off mature trees, and has been termed "tree mutilation" by tree guru Alex Shigo. Anyone who wants to understand how trees grow and respond to their environments is well advised to check his work out: https://shigoandtrees.com/ .
 
Cj Sloane
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Victor Johanson wrote:There is a difference between topping and pollarding. Proper pollarding is initiated when the tree is young and respects the tree's innate defense boundaries; it is a legitimate and longstanding arborist practice which actually extends logevity. Most of what's termed pollarding these days is just whacking the top off mature trees, and has been termed "tree mutilation" by tree guru Alex Shigo.


Pollarding is a very old technique going back to at least the Iron age:

The practice of collecting twigs and leaves for
fodder for domestic animals is a very old form for
fodder harvesting. Leaf fodder can be collected
efficiently with small iron tools and the practice has
a history at least back to the Iron Age
. Almost all
species of deciduous trees were used for animal
fodder, also some conifers. Although the harvesting
of trees for collecting fodder was widely practised
all over Norway, the choice of species, techniques
and utilization varied from area to area, as did the
names given to tree management.
Pollarding (“styving”) refers to the process of
topping trees, i.e. cutting back branches at a height
of 2-3 m, above reach of grazing animals.
Lopping
(“lauving”) is the actual fodder-collecting.


Either way (pollarding/topping) the life of the tree is extended if done properly.
 
Victor Johanson
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Cj Verde wrote:
Pollarding is a very old technique going back to at least the Iron age:


Yes, that's what I said--"Proper pollarding is initiated when the tree is young and respects the tree's innate defense boundaries; it is a legitimate and longstanding arborist practice which actually extends longevity." It isn't the same as topping a mature tree; it's done when the tree is young and composed mostly of sypmplast. Topping older trees is a harmful practice, but it gets done a lot anyway; since trees take a long time to decline and/or die, people think it's OK. Check out Shigo--you won't be sorry. He dissected more than 15,000 trees to understand the effects of various treatments. He knew his shit.
 
allen lumley
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Melvin H. : I am sorry I was not clear ! Valerie speculated on the Idea that Coppicing a Ash tree might have a protective effect or diminish the possible damage to that
tree from Emerald Ash Borers !

While this is reaching a bit I see no reason why it should not be looked into, we know what the alternative that all our Ash trees face.

At the present time my biggest danger is being downwind from Canada! Still searching for more information on the original topic !

I have a Copse of Elderwood endangering the foundation on an outbuilding that I have been Coppicing for years, local covens get 1st crack at the staffs,
Some have travelled much farther than Me ! For ALL the Crafts Big AL !
 
Cj Sloane
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Victor Johanson wrote:"Proper pollarding is initiated when the tree is young...


I wonder about the definition of young. Kind of a relative thing. A young fast growing tree will be quite different from a young slow growing tree.
 
allen lumley
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- O. K. : back on the original topic, Can someone recommend a listing of the generally correct times of the year for coppicing and pollarding ?

Certainly this information must have been compiled at some point !

2nd, it has been an established wood lot practice used for years in some of the Northeast to mark trees in the wood lot/sugar bush before fly
mosquito season, and then to girdle those trees meant for firewood, and allow the opening buds on the tree to dry out the tree. The trees were
then cut down and bucked up in the fall !

I assume from my exposure to this practice that this is counter productive to good Coppicing / Pollarding practices !? Big AL
 
Valerie Dawnstar
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Dave Jacke & Mark Krawczyk are currently writing a book on that very topic. Please see http://www.coppiceagroforestry.com/

I just 'spoke' with an arborist friend of mine who said coppicing won't work to keep the EAB away as it is very small itself and attacks small branches. So forget it for that reason. But maybe it would make it easier to spot... ?
 
Cj Sloane
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allen lumley wrote:- O. K. : back on the original topic, Can someone recommend a listing of the generally correct times of the year for coppicing and pollarding ?


In the Northern Hemisphere - when rainfall exceeds evaporation AKA the rainy season.

Although... I've been pollarding all summer and regrowth has been great.
 
Victor Johanson
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Cj Verde wrote:
Victor Johanson wrote:"Proper pollarding is initiated when the tree is young...


I wonder about the definition of young. Kind of a relative thing. A young fast growing tree will be quite different from a young slow growing tree.


That's probably true, but the main issue is that young trees are fundamentally different than old trees in that most of their mass is living tissue. This enables them to more vigorously respond to insults and injuries. Trees are generative organisms; they don't heal. Regenerative organisms (like us) replace damaged cells in their existing locations, which is what constitutes healing. Trees, in contrast, compartmentalize damage and grow new cells in a new location. The compartmentalization process walls off the damage, which will always remain. Some species compartmentalize better than others, and the response varies also among individuals within the same species.

Seriously--read Shigo. The guy was a genius and his research debunked many longstanding and deleterious treatments.
 
Steven Harris
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I have an ENTIRE BOOK called Firewood Crops Volume 1 and 2 at
http://www.knowledgepublications.com/books_by_title.htm

That book is about everything you can grow, in each climate, that can be used for firewood. These are fast growing plants for your region. This book is for ANYPLACE in the world where you would want to grow firewood. The objective of this book is to provide crops for 3rd world crap holes where people (women and children) walk for hours each day just to collect firewood for basic survival cooking. The intention of the book is to have rapid and continual firewood crops growing around and near the village instead of progressive deforestation.

So if you want a fast growing crop for your RMH, i'd check out this book.

Steve
 
Cj Sloane
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allen lumley wrote:
2nd, it has been an established wood lot practice used for years in some of the Northeast to mark trees in the wood lot/sugar bush before fly
mosquito season, and then to girdle those trees meant for firewood, and allow the opening buds on the tree to dry out the tree. The trees were
then cut down and bucked up in the fall !

I assume from my exposure to this practice that this is counter productive to good Coppicing / Pollarding practices !? Big AL


Yes, that is meant to kill the tree. A dead tree wont coppice as far as I know. I did girdle a few trees last year, only one wound up dead. Now it's had a year to dry out I really need to cut it down to check it out.
 
allen lumley
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Cj : In the past I used to do winter camping ! Those days are behind me, night will find me in my wee little featherbed (well the last part is true !) My two most
favorite camping spots are on an island with an old defunct beaver house and large hollow tree for a chimney of sorts ! and acres of dead trees from the beaver
flow in what was a large long meadow All that standing dead wood that paradoxically is very dry inches above the High water mark!

Number 2 is just below and inches away from a 6 foot tall beaver dam topped bank to bank with service berry and elderberry bushes that does an incredible job
of blocking the wind and creating a microclimate !

Like the R/R Engineers on the old TV show'' Pettycoat Junction '' who only burned the loose Ties from the R/R bed, I only steal a little sun dried wood from off of
the very top of the dam, as this location too has Acre feet of sun dried standing timber that lost its bark years ago !

These have been used for advanced base camps for finding lost hunters who decided their compass was broke, most wood lot managers will not touch this old
standing timber but- If used like kindling it burns hot and fast and can light up my beaver flow island like a light house ! Good wood will always vary from place
to place and use to use ! For the Good of the Crafts ! Big AL




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Lucas Harrison-Zdenek
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Doesn't geoff lawton talk about using coppice as the primary source of fuel for RMH? It seems to be the best option since it stores easily and dries quickly. It also fits right into the feed tube and can be cut long to feed over time.
 
Cj Sloane
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Yes. Though he mentions the old European technology, Kackleoffen, AKA Masonry heater.
 
Erica Wisner
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Richard Hauser wrote:This is both a RMH and a tree growing question, so excuse me if it is filed incorrectly.

RMH are efficient but still need fuel and I am lazy.
To avoid all that annoying sawing and splitting, I would it be possible to cut many .75" sprouts with a clipper, then dry and burn them whole.
With the way RMHs gravity feed, what would the best length and width of fuel be? Could you burn yard long twigs?
I was thinking of doing this with Black Locust as it is always claimed to grow fast, burn clean, hot and coppices well.
Is there a better choice?
Due to the laziness, I also didn't want to remove the bark. Will this cause a problem for drying?



Great thread!

I've definitely used coppiced wood, aka the big sprouts from our old hazelnut tree and fruit trees in Portland OR, we'd just clean up the new sprouts/poles a third of the tree at a time. We burned branches from brush, bundles of dried ivy/blackberry as firestarters, dried juniper leaves, half-rotted 'rescued' wood from other people's neglected yard debris piles, fallen branches from storms. All of it will burn well in a rocket stove if dried properly before burning. There are some parameters to watch; in general, if you have any problem with one type, size, or source of wood, you can often fix it by cutting, splitting, or mixing that wood with a different source to balance out the difficulties.

Length: I don't recommend using longer poles, for 2 reasons.
1) Wood mostly dries from its end-grain, so if you don't cut it, you have to wait longer for it to dry. We're talking about sizes of wood that, when dead-and-down, can be broken over the knee, or when cut live, can be lopped with heavy clippers or mostly severed with one blow of a sharp axe. It's not an unreasonable amount of work if you match your sizes and tools, and you'll save drying time.
2) Sticks taller than the fuel feed promote 2 dangerous problems: if there's more than 1 of them they can create little chimneys that draw flames and smoke up into the room, and even with only one of them, as the lower stick burns the upper part becomes top-heavy and can topple out and rock-and-roll its burning end around the room. Too-tall kindling has been partially responsible for at least one serious fire that I know of at Cob Cottage Co (it was combined with additional kindling on top of the barrel, another poor choice, and a heater burning unattended in a utility space while people were elsewhere).

Size: It all works, but I like the mix to include slightly bigger poles (2" or so) so they don't all burn down at once and choke the feed with coals.
(Geoff Lawton talks a lot about stick-fuels for rocket stoves in his videos. This isn't as much of a problem on the briefly-fired rocket stoves for Australian cooking and hot water applications, but in a home heater that I reload 3 or 4 times in a long firing, that firebox is hot enough to incinerate little twigs all at once by the time the last load goes in, and it all turns to one big mass of 3/4"-minus ember "gravel" and clogs the feed. I have to get over there and poke an air hole in it or it smokes back into the room, and being embers, it could emit CO without me noticing it, if it happened at the wrong stage of the burn. But for Geoff's sub-tropical stoves, that are used more briefly, he's right about smaller stick fuels being important. On a dense-brick stove that's only used briefly, you need to get the majority of the fuel itself up to temperature as quickly as possible, otherwise they burn dirty.)

Biggest: You can burn anything that will fit in the firebox; the bigger stuff is better later, once the firebox itself is very hot. I've successfully burned a round log that just barely fit into the firebox down to a 1" nub of charcoal, just burning on its own coals. but that doesn't always happen, and sometimes the fire burns down and sulks if it only has one piece of big wood to chew on. I like a few mid-sized branches or quarters off the smaller rounds to fit in around the edges, and keep the fire roaring brightly while it chews through that big chunk.

Smallest: For kindling, you can use bundles of dried twigs, splits from old cedar shakes or shingles, split cordwood kindling (Ernie does lovely match-thin splits off dried slabs, and keeps a little box full drying in a spark-safe area behind the heater), or any typical kindling. Dried bark-on branches will work if they're small enough; with practice, you can light the fire with a 'torch' of crackling-dry hemlock or pine twigs without even paper tinder.

Wood types: We've burned almost everything. There are a couple of types we often see minor problems with, but they can be mixed with other things for easier operation.

- Sawn lumber: Don't use painted, varnished, or heavily glued wood - this stuff can be uber-rich fuel and may emit toxic gick if it's too rich to burn clean in your present fire. Otherwise, clean lumber scraps can be burned. Watch out for an all-square wood load, or for wider flat pieces, they can end up acting like a damper and blocking the air-flow until they fully catch, and cause smoke-back. Sometimes I will burn a flat piece just being careful to orient it so air flows past it on both sides, in line with the burn tunnel like an open damper. With larger flat pieces like 2x6" or anything x6", I usually split them into thirds so I don't have to think too hard while loading the firebox. With the resulting pieces and anything roughly square, I like to mix them with round or split pieces so those flat sides can't gang up on me and turn into a damper by accident.

- Pitchy wood or "fat wood," green or wet wood, and some of the blistery-bark types: If the outside of the wood (or a pitch seam) burns faster than the core, the fire can reach the top of the feed before the foot of the wood has burned through and dropped. This is another reason to size your wood so it fits easily into your firebox - you can just slide a brick across the top and constrain the air, so the flame is forced down despite it being too high. Two bricks lets you reduce the air to as little as 25% of the opening, which is still enough to burn clean but makes a stronger, faster draft right in that narrow opening to keep it all burning properly. I use pitchy wood carefully - I sometimes cut it extra short, for example, and/or mix it with relatively dry, non-pitchy wood. Lighting the kindling fire with fatwood (cooked pitchy wood, like stumps after a forest fire) is a guilty pleasure; I know it makes extra soot, but it does hold a flame beautifully.

- Green and wet wood should not be burned in any responsible person's heater. The water content strips heat from the fire (evaporation), fills the firebox with steam (a fire extinguisher), and can consequently rob the firebox of more than half your fuel's heat value. They are also much more likely to produce smoke and creosote. And they just don't burn easily, or satisfyingly. If you are short of seasoned, dry wood (it happens, especially if you've been optimistic about your needs, or you've had to run the heater hotter to deal with unusual weather or make a sauna for a sick family member), then find the driest wood you can get. Standing dead wood (dry, dead branches) is better than wood that's fallen or been stored on the ground. The little branches under the skirts of evergreens are often quite nice and crackly-dry, even after any number of storms.

- Storage: Remember that wood's ability to suck up moisture and transport it along its grain structure almost defies the laws of physics. (You can only 'suck' water upwards about 30 feet using atmospheric pressure; how on Earth do trees grow and transpire moisture up to over 100 feet tall?!? They have wicked cool tree-magic.) Getting wood to dry out takes active management. Never store or "season" wood under a tarp on the ground - this is a lot closer to a mushroom-farm or a desert water-distillation trap than to a drying woodshed. Ground moisture rises up and gently steams the wood, then condenses on the tarp and rains/trickles back down. Any moisture in the wood is effectively trapped and magnified.

If you have to use a tarp to protect your woodpile, prop it up so there's airflow underneath, and tie it taut like a rain-fly or camp kitchen roof. You can suspend it between trees, or prop it up on a stick like a tent. Ernie's "re-usable trucker's hitch" or other tension hitches work great; you can get purchase anywhere on a tarp by tying the rope around a little round stone or wood-chip, so you don't need to puncture the tarp. Make sure the water has somewhere to go, that the eaves drain off well outside and downhill of the woodpile. And get the wood up off the damp ground. Use a couple of sacrificial poles crosswise as racks, or whatever.

Better yet, build one of Paul's skiddable woodsheds, or Caleb's pallet-wood-box-sheds, or anything with roof eaves and some kind of minimal, slat-like sides and floor.

Shapes: Generally, straight is a lot easier to work with than crinkly-curvy. I've had to give up on big old knotty gnarly forked pieces of oversized wood, if I can't cut them through the knots to make sections that fit in the firebox. Smaller twisty or wriggly pieces can be burned if you're careful, but it takes some work. Coppiced pieces sound awesome because those shoots tend to grow nice and straight. The suckers off orchard trees (or pollarded trees) work great in the same way. I've had some frustration with thorny types like plum and locust, because it's hard to feed them in past each other - but you can make bundles if you're willing to try, and burn them as units. I'd probably reserve these for making deer-resistant hedges, and use the straight stuff as firewood, if I have infinite choices.
If you decide to burn bamboo, make sure you cut, crack, or otherwise poke at least one hole in each hollow section. We have only burned unusable, cracked-out old dried bamboo, but I'm told that intact airtight sections will go off with a bang!

If it's just a question of what to plant for firewood - I'd plant what you want for other purposes, like fruit, nuts, or pole-wood for doing fences and wattle-and-daub and gardens and such. Then when you clean out the coppice and orchard every few years, the firewood is what's left over: oversized poles that you didn't use, garden stakes that have rotted down until they're too short to be useful, prunings from the fruit trees to keep them in good shape. I love burning pest-ridden wood, because few pests are going to survive in the rocket heater. (This may be one exception to the "never tarp it" rule - I've heard one of Paul's Montana experts talking about wrapping beetle-infested pine in black plastic to trap and kill the pests with heat, before attempting to re-use the wood.)

The perfect rocket fuel in my opinion is the kind of stuff that always ends up in the burn pile for our rural neighbors: big yard-debris that's too woody to compost.
If you can hook up with organic or spray-free orchards that don't use a bunch of pesticides, you may not need to plant anything at all.

-Erica W
 
Scott Arico
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...Remember that wood's ability to suck up moisture and transport it along its grain structure almost defies the laws of physics. (You can only 'suck' water upwards about 30 feet using atmospheric pressure; how on Earth do trees grow and transpire moisture up to over 100 feet tall?!? They have wicked cool tree-magic.)

There was actually some contention in the late 80's and 90's in the plant physiology field as to how trees are able to move so much water so high. After many studies, what they discovered is that the evapo-transpiration hypothesis was the best explanation for this tree magic. Essentially, when water evaporates from the leaves for cooling, it creates a partial vaccuum inside the leaf that will pull water from the xylem to relieve that pressure difference. And if all the leaves are doing it, than it can create very large pressure differences that will move water hundreds of feet up. Have you ever seen a little tree or herbaceous plant with water coming out of the ends of its leaves/needles? (you should only see it on a cool morning) Well, that is the plant trying to refill its cavitated xylem where air bubbles have formed becasue the pressure was too great. This is also why girdling works in most species, as the xylem is severed and no more water is available and those buds do in fact dry the tree out rather quickly.
 
Cj Sloane
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Awesome first post, Scott, welcome to Permies.
 
David Searles
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The University of Vermont did a study as to the best tree to grow for bio mass energy - to identify specifically which tree most efficiency converts sunlight into BTUs to be released by burning. The tree that best did that they found was fast growing Poplar trees.

 
Jack Edmondson
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Location: Central Texas zone 8a, 800 chill hours 28 blessed inches of rain
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Here is a broad list of woods by BTU per cord.

https://chimneysweeponline.com/howood.htm

I like to point out however, that that lowly bamboo at the very bottom (just above balsa wood) may look low. However when one converts to BTU per pound rather than cord it moves it along side Osage at the top of the chart. Bamboo grows faster and burns hot like coppice, and contains a higher btu rating than most trees. If you are going with a RMH and a wood lot, I would strongly recommend bamboo.
 
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