Wood ID
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smokinj
Minister of Fire
Wood Duck
Minister of Fire
I'd say most of it is cherry, but one large round standing on end appears to be Red Maple. both should season pretty fast.
firefighterjake
Minister of Fire
Some folks say cherry will season in as little as 6-9 months . . . and maybe it will . . . but in burning cherry, ash, elm, maple and what have you I can say that in my experience even the "fast-seasoning" trees burn a heckuva lot better given a year+ of seasoning . . . night and day difference in how fast the wood ignites, moisture left in the wood and how fast and intense the secondary burns occur.
That's not cherry, that's popple-pine, a dangerous wood to burn in any wood stove. I'll PM you about my free wood removal service so you can rid yourself of this hazard. ;-)
FFJ, I don't want to appear offensive, but I find myself not on board with this thinking.
As far as further seasoning giving better results, remember that the whole purpose of secondary combustion is to burn off the volatile wood gases and smoke that don't get burned in the primary combustion zone. If your secondaries are faster and more intense with drier wood, that can only mean that more smoke is being produced in the first place. Very dry wood pyrolizes much faster than moderately seasoned wood, in any type of stove, or even in an open fire.
As far as the OP's nice load of cherry (and that big red maple round), cherry is not a particularly fast drying wood. It is often (but not always) fairly low in moisture content when first cut, and I think that's why it has the reputation for being quick drying. Still, 6-9 months is plenty time to get it down close to 20%.
Here are a few tables from the book "Understanding Wood", by Bruce Hoadley.
They show a lot of things that seem to be at odds with what many folks here claim to experience. I won't go into why they seem to be at odds with that experience, but these tables were generated from data gathered by the lumber industry as it applies to air-drying 4/4 lumber, properly using very expensive moisture meters and, most likely, tens of thousands of samplings over the years. The amount of water leaving the ends of firewood is significantly greater than what leaves through the split faces, but we'll ignore that for now because the tables refer to long planks that only have a small amount of surface area at the ends compared to that of the faces. The tables clearly show that initial moisture content in a given species is not directly correlated with drying time.
For example, sugar maple is almost the same MC as white oak, but white oak takes almost twice as long to reach 20% MC as does sugar maple. And that pesky red oak that takes three years to dry in a wood stack? In conditions found in about 95% of the U.S., it dries to 20% in the same time as beech, birch, cherry and walnut. That's not my personal experience, but maybe that experience is a bit colored by memories of trying to burn it way too soon back in the good old days.
Yellow poplar ("tulip") is much higher in MC than even southern red oak, yet it dries in a relatively short time. Basswood is dripping with water when first cut, yet it dries very fast. And look how fast red maple dries. 30 days/inch thickness in optimal outdoor conditions! Pretty impressive for a medium-density hardwood.
Given the fact that wood dries through the split faces by establishing a diffusion gradient across the thickness of the wood, 2" thick red maple will take twice as long, and 6" thick, red maple will take 6 times as long, but that is still only a maximum of 6 spring and summer months for a quartered 12" round to hit the magic number. Actually, it will dry faster since much of the split will be less than 6" in thickness, and... OK, I'll mention it again. Short lengths of wood do a good amount of their drying through the ends.
I'm not trying to tell anybody how to burn, or to negate their wood burning experience, but this is real data from real wood drying experts gathered over decades, and it should not be just dismissed out of hand. I think one of the best things a new burner can do is to get copies of Hoadley's books and read them from cover to cover. Both "Understanding Wood" and "Identifying Wood" are available from Amazon for $26.37, with free shipping. Soon they'll be answering wood questions instead of asking them. ;-)
firefighterjake said:
FFJ, I don't want to appear offensive, but I find myself not on board with this thinking.
As far as further seasoning giving better results, remember that the whole purpose of secondary combustion is to burn off the volatile wood gases and smoke that don't get burned in the primary combustion zone. If your secondaries are faster and more intense with drier wood, that can only mean that more smoke is being produced in the first place. Very dry wood pyrolizes much faster than moderately seasoned wood, in any type of stove, or even in an open fire.
As far as the OP's nice load of cherry (and that big red maple round), cherry is not a particularly fast drying wood. It is often (but not always) fairly low in moisture content when first cut, and I think that's why it has the reputation for being quick drying. Still, 6-9 months is plenty time to get it down close to 20%.
Here are a few tables from the book "Understanding Wood", by Bruce Hoadley.
They show a lot of things that seem to be at odds with what many folks here claim to experience. I won't go into why they seem to be at odds with that experience, but these tables were generated from data gathered by the lumber industry as it applies to air-drying 4/4 lumber, properly using very expensive moisture meters and, most likely, tens of thousands of samplings over the years. The amount of water leaving the ends of firewood is significantly greater than what leaves through the split faces, but we'll ignore that for now because the tables refer to long planks that only have a small amount of surface area at the ends compared to that of the faces. The tables clearly show that initial moisture content in a given species is not directly correlated with drying time.
For example, sugar maple is almost the same MC as white oak, but white oak takes almost twice as long to reach 20% MC as does sugar maple. And that pesky red oak that takes three years to dry in a wood stack? In conditions found in about 95% of the U.S., it dries to 20% in the same time as beech, birch, cherry and walnut. That's not my personal experience, but maybe that experience is a bit colored by memories of trying to burn it way too soon back in the good old days.
Yellow poplar ("tulip") is much higher in MC than even southern red oak, yet it dries in a relatively short time. Basswood is dripping with water when first cut, yet it dries very fast. And look how fast red maple dries. 30 days/inch thickness in optimal outdoor conditions! Pretty impressive for a medium-density hardwood.
Given the fact that wood dries through the split faces by establishing a diffusion gradient across the thickness of the wood, 2" thick red maple will take twice as long, and 6" thick, red maple will take 6 times as long, but that is still only a maximum of 6 spring and summer months for a quartered 12" round to hit the magic number. Actually, it will dry faster since much of the split will be less than 6" in thickness, and... OK, I'll mention it again. Short lengths of wood do a good amount of their drying through the ends.
I'm not trying to tell anybody how to burn, or to negate their wood burning experience, but this is real data from real wood drying experts gathered over decades, and it should not be just dismissed out of hand. I think one of the best things a new burner can do is to get copies of Hoadley's books and read them from cover to cover. Both "Understanding Wood" and "Identifying Wood" are available from Amazon for $26.37, with free shipping. Soon they'll be answering wood questions instead of asking them. ;-)
Backwoods Savage
Minister of Fire
firefighterjake said:
Jake and I agree again! But yes, cherry can burn after 6-9 months of seasoning if it is split and stacked in the wind. At deer camp we used to just go out and cut some cherry and burn it right away. One had to keep a pretty good fire going all the time to keep it burning so used a lot of extra wood but it worked. But then, deer camp doesn't last that long either so we got along just fine. Most folks had enough alcohol in them they didn't need extra heat but some of us enjoyed it.
I know Battenkiller has his scientific reasons for disagreeing but we have our practical experiences to go by. So at least Jake and I will continue to season our wood and get nice clean burns with it.
Danno77
Minister of Fire
lol. I'll have to ask myself next time: "WWJD?" and if I can't figure it out I'll just ask ya.Jags said:
Danno77 said:
In the name of full disclosure - I would only use WWJD if it pertains to firewood, booze or food. Any other use is at your own risk.
Oh - and he did ask:
Jotul Rockland - CT said:
Danno77
Minister of Fire
I think there's a pretty good chance I already adhere to the Jags school of thought on that one....Jags said:
WoodPorn
Minister of Fire
Here are a few tables from the book "Understanding Wood", by Bruce Hoadley.
That chart shows Cottonwood @ 162%
And Sycamore @ 114%
How do you get 100+ % moisture content??
That chart shows Cottonwood @ 162%
And Sycamore @ 114%
How do you get 100+ % moisture content??
WoodPorn
Minister of Fire
daveswoodhauler
Minister of Fire
Just kiddin BattenkillerBackwoods Savage said:
And sailors thought they'd fall off the Earth because their observations told them it was be flat, so ships that failed to return to port must have gone too far and fallen off. Practical experience at work. This notion persisted long after the scientific discovery of the solar system and the Earth's spherical shape should have dispelled that thinking. :roll:
C'mon, Dennis, you know damn well I never said anywhere that wood didn't need to be dry. Unless "dry" (<20%) is not as good as "seasoned" in the outdoors.
Nice that you say you have all this experience, but new burners OTOH can't buy your 50 years of experience for all the money in the world, so they should pay careful attention to the lumber industry, because it gives very strong clues about what it takes to properly dry their wood. To wit:
- The only thing governing the final equilibrium content (EMC) of any wood anywhere in the world is the relative humidity of the air it is stored in. Period.
- Most areas of the country have an average yearly (that's day and night) relative humidity of over 70%.
- Wood stored at 70% relative humidity will eventually reach a moisture content of around 13% and will maintain that moisture content in equilibrium with the air surrounding it.
- The best time of year to harvest firewood varies according to species, with some having higher sap content in spring, some after the leaves drop in the fall. It pays to know your species.
- Air movement, more than any other factor, is clearly the major player in wood drying. Stacks should be well separated and be oriented perpendicular to the prevailing wind direction. That means faces of stacks exposed to the east and west for most of North America.
- Wood should be stacked as loosely as possible to get the air surrounding the splits to get as much moving air as possible. Water can only leave the wood at the very surface, and the air quickly gets saturated to near 100% RH inside the stack if the air flow is restricted in any way. No drying occurs at 100% RH.
- If you are in doubt about the moisture content of your wood, measure it with a device designed for the purpose. That's why they were invented. Harbor Freight sells one for the price of a new chain for the saw.
There is a huge difference between scientific theory and fact. Everything I have presented on this message board is a known fact, not some souped up theory I dreamed up while under the influence. For example, maple sapwood has a higher moisture content in the spring than it does in the fall. This is a fact based on simple and repeatable measurements. There are many hypotheses as to why it is higher, but to this date, no one is sure of why. That falls into the realm of theory. Pays to be able to tell the difference between the two.
Moisture content of greater than 100 percent means that there is more water in the wood than there is dry wood substance.
SolarAndWood
Minister of Fire
Battenkiller said:
Ok, but is close to 20% the ideal MC for burning firewood in a modern stove? I assume that drying to 13% looks a lot more like a decay function than linear? Maybe that extra year puts you somewhere in the high teens which produces more heat in a modern stove than close to 20%? The smoke dragon at the camp never complains about wood split in the spring but the new stove at home produces much longer burns with 18+ month dried wood.
My apologies to the OP; I burn cherry that was cut and split in the spring the following winter and it heats the house although I dry it longer now that I have the option.
Werm said:
Uh... uh.... Pay no attention to that chart behind the curtain.
:red: ;-P
Wait... oh, yeah....
oldspark said:
Oldspark knows his stuff. It's the way those stupid scientists express moisture content by convention. It has to do with consistency between the oven-dry method and... hell, let Dr. Hoadley explain it himself (click on the blue text below for the link):
www.finalfloor.org/techguide/maintenance/woodwater.pdf+moisture+content+wood+hoadley+method&hl=en&gl=us&pid=bl&srcid=ADGEESjTf3iikzreQarurL5jh9rAeC4unBTfo-2HjeZihBLmWpF9lQyz6pfLuLjqHXouQLtcCL8AWRXrwq7om4RyRkdKvVm-9f68U2PE-G5WFjrg4f2AFMm0X6WUMp_lO3JKnlG7pKEW&sig=AHIEtbTZihNcsJm4Z8KJ8GYMkbS_TH_-7w]Wood And Water[/url]
Bottom line is that there is a discrepancy between the way scientists express water content in wood and the way we intuitively think of it (i.e what percentage of a given piece of wood is water by weight). Scientists and wood technologists determine moisture content by dividing the amount of water in a piece of wood by the total weight of the wood after all the water is removed (commonly done by drying the wood in an oven). So, a piece of wood that weighs 1.5 pounds when wet, but weighs 0.5 pound when dry must have contained 1.0 pound of water when it was wet. We think of it as 2/3 water, or 67% water by weight, but wood techs express it as water lost (1.0 pound) divided by wood remaining (0.5 pounds) x 100 = 200%. The sapwood of some softwoods like pine and redwood actually contains over 200% MC when first cut (over 67% water by weight).
Since all moisture meters (and wood moisture charts BTW) are calibrated for the scientific method, we are stuck with their convention. That means that, for example, a piece of wood that reads 50% MC on the meter is only 33% water by weight, 33% on the meter means 25% water by weight, a 25% meter reading is 20% water and a 20% meter reading is 18% water by weight, and so on. The real significance of all this is that we are making too much out of the supposed moisture content of our firewood. The real difference by weight between a 10 pound split at 25% and one at 20% MC as read by a moisture meter in only 2% by weight, or 3.2 ounces. For all intents and purposes, they will burn the same in your stove, and will throw out nearly the same amount of heat.
Why?
A pound of wood at 0% MC will produce 8600 BTU of heat energy, but almost 10% of this heat is locked into the water vapor that is produced as a product of combustion itself (established at .54 pounds of water per pound of wood burned to completion). This is water that was never there in the first place, but was created inside your stove by combining the oxygen in the combustion air with the hydrogen atoms in the wood itself. Since the whole idea of exhausting flue gases is to get this out of the chimney before it condenses, you never regain this heat until is condenses into liquid water, which occurs outside of the chimney in the air. Therefore, all the charts that show heat output/pound of wood as 8600 BTU are not accurate in a wood heating scenario. Since about .54 pounds of water vapor is produced for every pound of wood burned, and you lose 970 BTU/pound of unclaimed latent heat in the combustion water, there is only about you only get about 8000 BTU of sensible heat per pound of oven-dry wood from a wood stove.
But we aren't burning oven-dry wood in the stove. Our firewood always contains (and should contain) some water content. You lose 970 BTU per pound of water by converting it from liquid water to water vapor inside the firebox. So out of a potential maximum sensible heat output of 8,000 BTU for 1 pound of wood at 20% MC (18% water by weight, or 0.18 pounds of water), we lose another 174.6 BTUs of heat. A similar 1 pound piece at 25% (20% water by weight, or 0.20 pounds of water) loses 194.0 BTUs. That is only a difference of 19.4 BTUs between two pieces of wood at 20% MC and 25% MC, respectively.
There is a much greater difference in heat output between any two pieces of wood from different parts of the same tree than 19.4 BTUs. If you are finding things that don't conform to the physics and math behind all this stuff, you are in possession of a magic stove... and I want one. ;-)
That's the short version, DWH, is that OK? If not, I can give you the long version, but I'll need to use 2-3 posts due to the 6000 character limit per post on this forum. :lol:
Todd
Minister of Fire
Battenkiller said:That's not cherry, that's popple-pine, a dangerous wood to burn in any wood stove. I'll PM you about my free wood removal service so you can rid yourself of this hazard. ;-)
firefighterjake said:
FFJ, I don't want to appear offensive, but I find myself not on board with this thinking.
As far as further seasoning giving better results, remember that the whole purpose of secondary combustion is to burn off the volatile wood gases and smoke that don't get burned in the primary combustion zone. If your secondaries are faster and more intense with drier wood, that can only mean that more smoke is being produced in the first place. Very dry wood pyrolizes much faster than moderately seasoned wood, in any type of stove, or even in an open fire.
As far as the OP's nice load of cherry (and that big red maple round), cherry is not a particularly fast drying wood. It is often (but not always) fairly low in moisture content when first cut, and I think that's why it has the reputation for being quick drying. Still, 6-9 months is plenty time to get it down close to 20%.
Here are a few tables from the book "Understanding Wood", by Bruce Hoadley.
They show a lot of things that seem to be at odds with what many folks here claim to experience. I won't go into why they seem to be at odds with that experience, but these tables were generated from data gathered by the lumber industry as it applies to air-drying 4/4 lumber, properly using very expensive moisture meters and, most likely, tens of thousands of samplings over the years. The amount of water leaving the ends of firewood is significantly greater than what leaves through the split faces, but we'll ignore that for now because the tables refer to long planks that only have a small amount of surface area at the ends compared to that of the faces. The tables clearly show that initial moisture content in a given species is not directly correlated with drying time.
For example, sugar maple is almost the same MC as white oak, but white oak takes almost twice as long to reach 20% MC as does sugar maple. And that pesky red oak that takes three years to dry in a wood stack? In conditions found in about 95% of the U.S., it dries to 20% in the same time as beech, birch, cherry and walnut. That's not my personal experience, but maybe that experience is a bit colored by memories of trying to burn it way too soon back in the good old days.
Yellow poplar ("tulip") is much higher in MC than even southern red oak, yet it dries in a relatively short time. Basswood is dripping with water when first cut, yet it dries very fast. And look how fast red maple dries. 30 days/inch thickness in optimal outdoor conditions! Pretty impressive for a medium-density hardwood.
Given the fact that wood dries through the split faces by establishing a diffusion gradient across the thickness of the wood, 2" thick red maple will take twice as long, and 6" thick, red maple will take 6 times as long, but that is still only a maximum of 6 spring and summer months for a quartered 12" round to hit the magic number. Actually, it will dry faster since much of the split will be less than 6" in thickness, and... OK, I'll mention it again. Short lengths of wood do a good amount of their drying through the ends.
I'm not trying to tell anybody how to burn, or to negate their wood burning experience, but this is real data from real wood drying experts gathered over decades, and it should not be just dismissed out of hand. I think one of the best things a new burner can do is to get copies of Hoadley's books and read them from cover to cover. Both "Understanding Wood" and "Identifying Wood" are available from Amazon for $26.37, with free shipping. Soon they'll be answering wood questions instead of asking them. ;-)
This chart is for 4x4 lumber with no bark which will make a huge difference. Think of a 4" round of red oak with all the bark on it as long as the above 4x4's, it will take at least twice as long to dry as a barkless 4x4. And where do they take their moisture readings? Do they split the 4x4 in half and take it from the middle like we do firewood or just stick it on the outside? With my cheap moisture meter a fresh split of red oak pegs out at 42% and takes 2 years to reach 17-20% and some larger rounds can still be sizzlers.
WoodPorn
Minister of Fire
This chart is for 4x4 lumber with no bark which will make a huge difference. Think of a 4" round of red oak with all the bark on it as long as the above 4x4's, it will take at least twice as long to dry as a barkless 4x4. And where do they take their moisture readings? Do they split the 4x4 in half and take it from the middle like we do firewood or just stick it on the outside? With my cheap moisture meter a fresh split of red oak pegs out at 42% and takes 2 years to reach 17-20% and some larger rounds can still be sizzlers.[/quote]
No, this chart is for 4/4 lumber -or- four quarter lumber -or- 1" lumber.
No, this chart is for 4/4 lumber -or- four quarter lumber -or- 1" lumber.
Some body correct me if I am wrong but an awful lot of my splits and the pictures of splits on this site have no bark what so ever.
Werm said:
I fully realize this. As I said in my original post:
I am not making any claim that big splits of oak will dry in 6 months, just giving some objective information about the differences in drying rates between various species of wood. I was a bit surprised to see that cherry took so long to dry to 20% when I first saw this. I burned it with short seasoning for years, ash as well. Never had a problem.
Remember, wood in air-drying lumber yards is carefully stacked and properly stickered to give maximum air flow between the boards. We don't always pay that much attention to air spaces and stack orientation as we should. That may have a slowing effect in some cases. But there is also the fact that there is a lot of exposed end grain in short pieces of firewood. 12" splits or rounds will dry much faster than 24" pieces of the same diameter.
Anyway, the original point was to show that cherry (the subject of the OP) actually dries slower than wetter woods like red and hard maple, which is contrary to what most folks (including myself) seem to experience subjectively. I still think 6-9 months produces good cherry firewood in most spots in the nation if given enough wind and kept out of periods of constant rain.
I can come up with info all day long to support what you are saying Battenkiller but I think it is going no where. :exclaim:
Todd said:
Most pro yards use big impact electrodes called "slide hammers" (see attached photo) connected to expensive Delmhorst resistance-type meters. You're looking at about $600+ for a setup like that. They are capable of penetrating very deeply into the board, up to about 1 1/2". That allows them to get an average of the diffusion gradient that exists on both sides of the board. They can get a species-corrected reading that is accurate to a few percentage points on lumber up to 6" thick if needed.
Green oak is sometimes well over 80% MC. So what if your cheap meter pegs out at 42%? Most of the Delmhorst ones only go to 30%. That's because no meter is that accurate much about the fiber saturation point of the wood, which is pretty much between 28-30% for most known species. No one dealing with either lumber or firewood really cares about the initial readings anyway, it's the MC of the finished product that is important. If you really want to know the original MC of green wood, use the oven-dry method. It is 100% accurate in all cases and on all woods.
In the meantime, I'll dry my oak for 2-3 years as well. I'm convinced the stuff never dries. ;-)
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