# tree weight



## abbott hill (Mar 17, 2004)

how much would a 100ft pine tree weight at most in maine


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## NYCHA FORESTER (Mar 17, 2004)

http://www.woodweb.com/cgi-bin/calculators/calc.pl?calculator=log_weight


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## John Paul Sanborn (Mar 17, 2004)

It is not just the hight of a log, but the average diameter you need to know.


You take the equasion of the volume of a cyliners and multiply by the average green wood weight.

Take a 40 inch dia log of oak.

40/12=3.33

3.33x3.33 is about 10

pi is about 3.14

If the oak weighs 55#/cuft

(10x31.4)55=2041per liner foot

With the green weight tables, a tape and the formual, one can become pretty accurate in guestimating the weight of a log in the frield.


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## Gypo Logger (Mar 17, 2004)

Math is a wonderful thing and it's fun to use it with wood.
Anyway, a good method is to translate the volume into cords or footage.
Therefore, if a Hard Maple at 20" dbh has a merchantable log length of 30 ft. it will have approx. 250ft. including defects etc. or 1 full cord. The crown would weigh about half that much if it was a forest tree. Therefore the average 20" maple would weight 4 tons. One bf of MH weights 13.5 # in roundwood form.
Since pine is half the weight, but taller and smaller of crown, I would think a 20" White Pine would weigh 3 tons depending on time of year and MC.
It sounds good anyway, doesn't it?
John


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## rmihalek (Mar 17, 2004)

*log weight*

The equation for volume of a cylinder is "pi" times the radius squared times the height. 

For a 40 inch diameter log, the radius is 20 inches, this is 1.667 feet. If you square 1.667 you get 2.78. Multiply 2.78 by pi (3.14) and you get 8.73. So, for every foot of length of this 40" diameter log, you have 8.73 cubic feet of wood. At 55 pounds per cubic foot, you have 480 pounds per linear foot of log.

JPS, you squared the diameter instead of the radius and also used 31.4 in your calculations, not 3.14, hence the figure of over a ton per foot.


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## Gypo Logger (Mar 17, 2004)

The volume of a cylinder works nice on sawlogs if the tip dia. is known since measuring the tip accounts for taper.
If a 40" dbh tree has a 26 ft. log in it there will be 1000bf. and at 13.5# it would weigh about 6.75 tons and assuming the tree was 80 ft. the crown should weigh an additional 2.5 tons if it had a full cord in it. So a 40"dbh stem should weigh around 10 tons, however this is more reflective of the volume once the tree is sawn up, so I would think a more accurate estimate would be 11-12 tons for a Hard Maple 80 ft tall and 40" dbh.
Here is a helpful timber estimate.
John


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## Gypo Logger (Mar 17, 2004)

Furthermore, "says the professor", lol.
Since a 20" is half the size of a 40", it is fair to say that the 20" has 1/4 the volume and therefore weight of the 40" stem.
These are just averages and not to be construed as accurate, but rather rule of thumb.
John


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## John Paul Sanborn (Mar 17, 2004)

> _Originally posted by Gypo Logger _
> *fair to say that the 20" has 1/4 the volume and therefore weight of the 40" stem.*



I toght it was closer to 1/3. If guessing mbf you would want to err low, if guessing pick weight err high.


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## John Paul Sanborn (Mar 17, 2004)

Yup I sqaured d not r, which is why I came up with 10, (3.33 x3.33)x3.14 I just rounded d-squared.

When i think about it, 590# seems much better.

That's why I have the formula writen down on the wood weight chart


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## Gypo Logger (Mar 17, 2004)

Hi John, I was thinking 4X, since when we double the size of something we quadruple its area and therefore weight.
Most people believe that trees don't grow that fast, but when we have a large area of trees that are uneven in age there are always a certain amount of mature crop trees that can be harvested on a regular basis, hence sustained yeild logging.
It makes me wonder what the trees and forests looked like 100 years ago when they were seen as an obstruction.
John


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## Stumper (Mar 17, 2004)

abbott hill, As others have mentioned-more than height needs to be known. Butt diameter is a big help but there are still variables-sparcity or fullness of the crown, water content, growth rate(within the same species the speed that the tree grew will cause changes in density) earlywood/latewood ratio(more density stuff) You asked for maximum weight so I'll throw out a qualified figure--If butt diameter is 30 inches and height 100 ft a green pine will probably not exceed 7000 lbs. by much.


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## igetbisy (Mar 18, 2004)

> _Originally posted by NYCHA FORESTER _
> *http://www.woodweb.com/cgi-bin/calculators/calc.pl?calculator=log_weight *



enough for me, cant beat that, thanks


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## Kneejerk Bombas (Mar 18, 2004)

> _Originally posted by Stumper _
> *-If butt diameter is 30 inches and height 100 ft a green pine will probably not exceed 7000 lbs. by much. *



I stuck a 30 inch log into that calculator and a 20 foot section weighs almost 5000 pounds.
With that in mind, I'd say you're on the low end with that guess.
I'd say two or three times that.


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## Stumper (Mar 18, 2004)

Oops! Brain fart. a *24 inch butt* and 100 ft height shouldn't exceed 7000 lbs by much. That is based upon my experience of hauling several trees of that size to the scales. I don't know why 30" popped out in my post-probably because I'm supposed to give a bid on a bunch of stumps today-supposedly 30 inchers.


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