# How many trees make a cord



## steviep (May 21, 2008)

I am planning to cut down some trees this weekend. Most are 8 inch or larger and at least twenty foot before you get to the branches. Just trying to figure how many trees i need to get 7 to 10 cords.


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## Stihl051master (May 21, 2008)

You'd just have to figure the volume of each log. A cord is 128 cubic feet. The formula for volume is pi(about 3.14159) x radius squared x length ( do all measurements in feet). For example, if you had a 12" round log that was 20 ft long, it would work out to just under 63 cubic feet. So, if you wanted 10 full cords, you'd need a bit over 20 logs. 7 full cords would be a bit over 14. Hope this helps!


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## turnkey4099 (May 22, 2008)

Stihl051master said:


> You'd just have to figure the volume of each log. A cord is 128 cubic feet. The formula for volume is pi(about 3.14159) x radius squared x length ( do all measurements in feet). For example, if you had a 12" round log that was 20 ft long, it would work out to just under 63 cubic feet. So, if you wanted 10 full cords, you'd need a bit over 20 logs. 7 full cords would be a bit over 14. Hope this helps!



Errmmm...not quite right. A cord is defined as a 'tightly stacked' pile that contains 128 cu ft, 4x4x8 for example. But that 128 cu ft contains a lot of air space no matter how tightly stacked. Thus you sample above will stack (tightly) to considerably more than 63 cu ft.

Harry K


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## mga (May 22, 2008)

steviep said:


> I am planning to cut down some trees this weekend. Most are 8 inch or larger and at least twenty foot before you get to the branches. Just trying to figure how many trees i need to get 7 to 10 cords.




i think you'll be cutting up alot of them to get a full cord.

trees look big when they're standing there, and when cutting they seem to get bigger...lol.... but, once split and stacked, they sure seem to shrink.


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## Engineeredlawns (May 22, 2008)

Stihl051master said:


> You'd just have to figure the volume of each log. A cord is 128 cubic feet. The formula for volume is pi(about 3.14159) x radius squared x length ( do all measurements in feet). For example, if you had a 12" round log that was 20 ft long, it would work out to just under 63 cubic feet. So, if you wanted 10 full cords, you'd need a bit over 20 logs. 7 full cords would be a bit over 14. Hope this helps!



Not exactly correct. The radius is the measurement from the middle of the circle to the outside. THe diameter is the measurement from outside to outside. Logs are measured by diameter. Here is a chart I did to get the volume per ft of log.

Diameter Volume Ft	Length for a cord
8	0.35 286.62
10	0.55 183.44
12	0.79 127.39
14	1.07 93.59
16	1.40 71.66
18	1.77 56.62
20	2.18 45.86
24	3.14 31.85
26	3.69 27.14
28	4.27 23.40
30	4.91 20.38
36	7.07 14.15

I figured the lenghts using 100 cf for a cord due to the fact that split wood stacked has some space. 67 CF may be a better figure. What ever you want to use, say 67 cf, devided that by the volume per foot to get the lenght needed. 12" log 67 cf stacked for a cord 67/.79=84.8 feet needed for a cord.

Hope this helps


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## Nuzzy (May 22, 2008)

Stihl051master said:


> The formula for volume is pi(about 3.14159) x radius squared x length ( do all measurements in feet).





Engineeredlawns said:


> Not exactly correct. The radius is the measurement from the middle of the circle to the outside. THe diameter is the measurement from outside to outside. Logs are measured by diameter.



Stihl051 is correct on how to find volume. Pi x r^2 x length

Yes logs are usually measured in diameter but in order to calculate volume, you must use the radius (half the diameter).

However, it is true that a cord (the way it's written) takes into effect airspace in a tightly stacked pile of wood.


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## darren_nh (May 22, 2008)

I have read in a few places that a tree with an 18" DIAMETER trunk cut (including tops and such) yields about a cord of firewood. I have yet to test this myself, but seems about right.


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## ropensaddle (May 22, 2008)

So how many cords is in a tree with five cords of limb wood?
I cut a very large make that huge oak that was killed in a lightning
strike the owner saved all wood down to five inch diam and the tree had five full cords of limbwood. I was not there to see what the 56" dbh trunk netted so I am guessing another two so a seven cord tree!


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## Booshcat (May 22, 2008)

This is a grapple load that was sold as 7 Cord....
The guy actually said he threw on some extra for me.

Looks like a lot of wood on the truck

When dumped on the ground it sure looks like less

I guess I wont know till It's all split.

Oh yeah, I paid $85 a cord or $595

I'm hoping it's two years worth for me.


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## blackdogon57 (May 22, 2008)

*Grapple Load*

I buy a lot of firewood logs for processing and resale and it looks to me that that load is not close to 7 cords. You should count on around 6 cords for a properly packed single grapple load. Tough to tell from a couple of pictures but that load does not look to be well packed on the truck and has several bent logs that create air space on the load. The grapple also takes up a lot of space on top of the load. There are also several logs that look like they are punky in the middle. If I had to make a best guess based on what it looks like on the ground I would say you have around 5 to 5.5 cords. Please post actual amount when you cut split and measure.

Good luck !


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## flewism (May 22, 2008)

This spring I dropped a 22" shagbark hickory that I computed was about 48' tall with 14' of straight trunk. I got just over 1 1/2 full cords out of it total cutting everything 3" and larger. 3 years ago I bought 2 "grapple loads" of ash for $150 each and I got about 4.5 full cords out of each pile. I didn't see the wood on the truck , just a pile of logs when I got home from work. I now wish I'd bought 10 loads then as they only did that for that one year at that price.


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## Stihl051master (May 22, 2008)

Whoops! When I figured the volume for the 12" round it should have been about 15.7 cubic feet (hey it was late). I gave the volume for a 24" round 20' long at 63 cubic feet. At any rate the guys are right that a cord of wood is 128 cubic feet tightly stacked, so with the airspace you would get always get more wood no matter how tightly you stacked it. I just figured this way if you needed a minimum amount you wouldn't "cut yourself short".... It's just a rough idea anyway, trees don't often grow perfectly round and the same diameter from ground to top.


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## darren_nh (May 23, 2008)

Booshcat said:


> This is a grapple load that was sold as 7 Cord....
> The guy actually said he threw on some extra for me.
> 
> Looks like a lot of wood on the truck
> ...



That looks to be a small grapple load. I received mine on Monday and is at least half again larger. Theguy isn't doing you any favors by dumping is right on the ground. Next time ask him to place a couple of transverse logs on the ground before offloading the truck so the entire pile isn't sitting on the ground. I typically request nothing over 16" in diameter as I don't want to lift large rounds onto the splitter if I can help it.


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## Husky137 (May 23, 2008)

Booshcat said:


> This is a grapple load that was sold as 7 Cord....
> The guy actually said he threw on some extra for me.
> 
> Looks like a lot of wood on the truck
> ...




It looks like less because it is. A lot of junk in there too. You got screwed.


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## BlackCatBone (May 23, 2008)

Nuzzy said:


> Stihl051 is correct on how to find volume. Pi x r^2 x length
> 
> Yes logs are usually measured in diameter but in order to calculate volume, you must use the radius (half the diameter).
> 
> However, it is true that a cord (the way it's written) takes into effect airspace in a tightly stacked pile of wood.



How about this then: Pi/4 * D^2


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## Nuzzy (May 23, 2008)

BlackCatBone said:


> How about this then: Pi/4 * D^2




Still need to factor in length 

Good math though. Took me a second to wrap my mind around it :greenchainsaw:


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## acer saccharum (May 23, 2008)

You can think of it this way for a quick estimate.

If your log could be a perfect 8" diameter end to end. (which obviously is not the case.)
Make a row of 6 logs side by side and your row is 4 feet wide.
Stack 6 of those rows on top of each other to get 4 feet high.
36 logs total. 
So if they are 8' long you have a cord. Obviously after cutting and splitting it will stack up differently. 

Same logic on 10" logs, 5 side by side = 50" which is close to 4', so you will need 25 10" logs 8 feet long are about a cord. 

12" logs, 4 make 4', so your pile needs to be 4x4 or 16 8' logs.


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## ray benson (May 23, 2008)

Page 1 has a chart for trees per cord. Page 2 has tree characteristics for firewood.
http://www.ianrpubs.unl.edu/epublic/live/g1554/build/g1554.pdf


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## Firewolf (May 24, 2008)

Booshcat said:


> This is a grapple load that was sold as 7 Cord....
> The guy actually said he threw on some extra for me.
> 
> Looks like a lot of wood on the truck
> ...



I think you might have maybe 4 1/2 to 5 cords not 7
Big stuff it could be better but the price is right?


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## Tazman1602 (May 24, 2008)

Booshcat said:


> This is a grapple load that was sold as 7 Cord....
> The guy actually said he threw on some extra for me.
> 
> Looks like a lot of wood on the truck
> ...



Man I don't know. That looks a bit shy of 7 cords to me. I just got this ten cord load for $750.


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## blackdogon57 (May 24, 2008)

*Now thats a nice load of logs !!*



Tazman1602 said:


> Man I don't know. That looks a bit shy of 7 cords to me. I just got this ten cord load for $750.



Nice load of wood !! Was this all one 1 standard triaxle or was it truck plus pup or some other type of rig ?? Looks like at least 10 cord to me. If it was a properly loaded standard truck plus pup you should get 12 plus cord. Good price too. That load here in Ontario would cost $1400 to 1600. I wish I could bring in logs from MI.


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## Tazman1602 (May 25, 2008)

blackdogon57 said:


> Nice load of wood !! Was this all one 1 standard triaxle or was it truck plus pup or some other type of rig ?? Looks like at least 10 cord to me. If it was a properly loaded standard truck plus pup you should get 12 plus cord. Good price too. That load here in Ontario would cost $1400 to 1600. I wish I could bring in logs from MI.



Man I wasn't here when they delivered. I've bought from them before and they know where to put it and it just shows up one day. The last load was a packed full truck (dual rear axle log truck with grapple) as I recall. 

I've got another load like this one coming in about three months. That one I'll let season until December and then start cutting. Skidding off is easier in the snow. 

We cut out back on our property as well, keeping the woods in shape, but it's probably more cost effective to buy in loads like this. Getting it out of the woods is a lot of work even with a truck and a tractor.


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## blunt (May 26, 2008)

Tazman1602 said:


> Man I don't know. That looks a bit shy of 7 cords to me. I just got this ten cord load for $750.



Thats one tasty looking pile of logs! Makes me want to crank up my J'red!


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## Tazman1602 (May 27, 2008)

blunt said:


> Thats one tasty looking pile of logs! Makes me want to crank up my J'red!



We did this weekend. Got to use the new 372XP for a few tanks. That saw is a monster compared to my 353 with muffler mod. The 372 doesn't need a mod. It just keeps on chewing................

I can skid and cut more logs with that saw than the girls can keep up with on splitting................

Now if my freakin elbow will just quit hurting...............<grin>


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## thenorth (May 27, 2008)

what about (D^2*Pi/4)*L

john


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## MattB (Jul 10, 2011)

The numbers I've seen posted else where is a cord is about 90 ft3 unsplit or 180 ft3 as a hand tossed pile. 

This is a great log weight calculator that I've used for some crane jobs. If you know how much a cord of wood is supposed to weigh you can figure it out. 
Log Weight Calculator at WOODWEB

Here is the chart for cord weight by species
Tree Species and Firewood BTU Ratings Chart for Heat Energy Content

Random factoid, most wood is about 50% moisture content when fresh cut, to bring it down to 12% each cord has to loose 72 gallons or 600lbs. 

Love the firewood talk...I'm designing a splitter to process logs to 6' diameter...in theory with the right sized logs I'll be able to process a cord into about 650 pieces in 5 mins. I'll post pictures when it is built.


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## ponyexpress976 (Jul 11, 2011)

To the OP, anyway you look at it, cutting firewood, especially out of 8-12" logs, to get to your total is a butt load of cutting. Given your location and winter temps figure at least 35 trees if not 40 if they are all close to 8" to hit your needs and have some to spare...just in case old man winter hangs around for a few extra weeks.


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## burningwood (Jul 11, 2011)

steviep said:


> I am planning to cut down some trees this weekend. Most are 8 inch or larger and at least twenty foot before you get to the branches. Just trying to figure how many trees i need to get 7 to 10 cords.




http://extension.unh.edu/resources/files/Resource001044_Rep1200.pdf

bw


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## forestryworks (Jul 11, 2011)

A cord OCCUPIES 128 cubic feet of space. It does not CONTAIN that volume. Volume differs based on how you split and how you stack.


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## lfnh (Jul 11, 2011)

decent link for scaling standing timber.

also scaling stick not to spendy.


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## CJ1 (Jul 11, 2011)

Just for reference I cut up 8 foot of tree last weekend and got a cord and a half out of it. 54" at the base, so yea it really does differ. CJ


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## Wood Doctor (Jul 11, 2011)

*Lots and Lots*

I've processed about 17 mature trees this year (much bigger than yours) and I have about 15 cords split and stacked. I'll sell about half and keep the rest for my stove. Believe me, it takes more trees than most people realize to get enough firewood to heat a house or two.

Lots of variables are involved, including both trunk and crown size. Sometimes you think a tree is a winner until you discover that half of it has been infested with carpenter ants and/or eaten by termites or other critters.


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## GeeVee (Jul 11, 2011)

forestryworks said:


> A cord OCCUPIES 128 cubic feet of space. It does not CONTAIN that volume. Volume differs based on how you split and how you stack.


 
Works says all you need to know.....


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## Wood Doctor (Jul 11, 2011)

*Rounds vs. Split...*



GeeVee said:


> Works says all you need to know.....



But, if he piles up firewood-length rounds cut from the trees and fails to split them, what does he have then?


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## TMFARM 2009 (Jul 11, 2011)

mga said:


> i think you'll be cutting up alot of them to get a full cord.
> 
> trees look big when they're standing there, and when cutting they seem to get bigger...lol.... but, once split and stacked, they sure seem to shrink.


 
its kinda like buck fever.. the buck looked bigger then a dog inside the woods...:hmm3grin2orange::hmm3grin2orange:


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## TMFARM 2009 (Jul 11, 2011)

Wood Doctor said:


> But, if he piles up firewood-length rounds cut from the trees and fails to split them, what does he have then?


 
piles of unsplit rounds duh!!!!


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## Mass. Wine Guy (Apr 1, 2013)

I am so dreadful at math that I'd die if my life depended on it If I have a tree about 12 inches in diameter and, say, 30 feet long, how much of a cord would that furnish, roughly?


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## MattB (Apr 1, 2013)

Mass. Wine Guy said:


> I am so dreadful at math that I'd die if my life depended on it If I have a tree about 12 inches in diameter and, say, 30 feet long, how much of a cord would that furnish, roughly?



It depends on the size of the short end, how much bark you loose and how much shrinkage while drying. 

but 12" large end, 8" small end inside bark and 30' long should give you something like 16 cubic feet. If you can get 6 logs just like that you'll have about one cord.


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## slowp (Apr 1, 2013)

A PNW log truck holds close to 10 cords. A load of 40' peckerpoles is anywhere from 80 to 100 logs. Double that for 20' peckerpoles and you come up with 160 to 200 trees for a load. 

How do I know this? I worked on lodgepole pine units that were logged. The log scaling program at the mill had to be adjusted because there were more logs on trucks than the computer was programmed to handle.

Now, how many camels can dance on the tip of a needle? How many grains of sand are in a bucket? If I trip and fall in the blackberries, and nobody is there, did I actually fall?


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## Mass. Wine Guy (Apr 1, 2013)

Thanks, guys. At least now I have a rough estimate. Every time I get wood delivered I understand how much wood each cord is. I went to college in Washington State and always wondered how much wood those trucks were hauling.


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## MattB (Apr 1, 2013)

Mass. Wine Guy said:


> Thanks, guys. At least now I have a rough estimate. Every time I get wood delivered I understand how much wood each cord is. I went to college in Washington State and always wondered how much wood those trucks were hauling.



Here in California we have very low load limits on trucks so the trailers are always capped by weight rather than volume (assuming the trucks have to pass through a weigh station)

If you know the species and you know the tare weight of the truck and trailer and the truck has been weighed, it is easy to figure out how many cord you have. 

Where I'm at we have limits of 80k combined. A self loader truck and trailer tare out at about 40k so you can get 40k lbs of wood. If it is douglas fir, figure about 4,000lbs a cord green so you can get up to 10 cord delivered at a time. It always depends though, small logs take up more space, you'll probably need 40' logs to max out weight with a single trailer ect.


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## Wood Doctor (Apr 1, 2013)

steviep said:


> I am planning to cut down some trees this weekend. Most are 8 inch or larger and at least twenty foot before you get to the branches. Just trying to figure how many trees i need to get 7 to 10 cords.


This one tree produced five cords:






A couple of these and you are done.


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