Weight of tree for crane removal

[WPTS]

Heloo fellas,

Just wondered if anyone could supply me with a formula for calculating the taper of a stem and therefore an accurate mass of a tree. Trying to put together method statement for crane removal and specs for hardware / software required so a degree of accuracy is paramount!

Thanks G

 

[chep]

I think you are trying to find the volume of a section of a tree?

the easist way to get the volume of the tree is to use Smaliens formula for cubic feet, then convert to lbs/cubic foot for that species.

SMALIENS FORMULA

B+b/2 x L

B= at big end of section, Diameter squared x .005454
b= small end of section, Diameter squared x .005454
L= legnth in feet
.005454 is the basal area conversion #

so if you have a stem that has a diameter at the large end of 12 inches and at the small end of 8 inches and is 16 feet long, then it goes as following

12 squared= 144 x .005454= .785376
8 squared = .349056
sum of the two= 1.134432/2= .567216
.567216 x 16= 9.075456 CUBIC FEET

I hope that is what you are looking for, guess you need to look up the green weights by cubic feet for different species next.
good luck

 

[CHOPPER]

Alot of variables to work with so complete accuracy will be near impossible to come up with!
An experienced crane operator who specialises in tree removals with an on board computer would be your best bet for accurate info

 

[joe]

Chep: I noticed the diameters are measured in inches and the length is measured in feet. Do you think the example would be better represented if the same units, inches or feet, were consistently used throughout all the equations?

Joe

 

[chep]

The formula is straight out of my Forest Measurements Textbook... the B and b calculation if you look a bit closer is converting a diameter (inches) into an area value (square feet). then in the end you are multiplying by length (feet). So all number are in the same units by the ends. I understand where you might see a bit of confusion, but if you look at it and follow it through, it makes sense....

There are a few more cubic foot formulas as well,

Huber's volume = (B @ midpoint of log) X Length(ft)
B= basal area @ midpoint of log

Newton's volume= (B+4B+b)/6 x Length

The formula that I provided (smaliens)is consistent and accurate...
good luck

 

[chep]

Oh,
Chopper has a great point, but this formula is quite accurate if your log has a consistent taper, and doesnt do anything crazy... But how often does that happen?

 

[jomoco]

This is a decent log weight calculator by species.

http://www.woodweb.com/cgi-bin/calculators/calc.pl

jomoco

 

[Mahk_Adams]

Look at this discussion:

http://www.treebuzz.com/forum/showflat.p...;gonew=1#UNREAD

and the links, especially the link to Technical Bulletin 479.

The chart that I provided is now in the Articles section here on TBzz.

 

[Colin]

i think your math is a little flawed chep, i mean this in a non critical way. i just pulled this off doctor math.comCubic Footage of a Tapered Log

Date: 08/07/2002 at 18:42:15
From: Christopher Watkins
Subject: Cubic Footage of a Tapered Log

Is there an equation that will calculate the cubic footage of a log
given the diameters of each end and the length?

Currently, I am using Smalian's Formula:
(Area1 + Area2)/2 x Length (ft)
Area = .005454 x diameter^2

Is there a formula that is more accurate by accounting for the taper
in the log?

Example:
Diameter1 = 9.2 inches
Diameter2 = 10.3 inches
Length = 102.84 inches
Smalian's calculates 4.443 cubic feet.

it seems that the variables have to be the same as in any equation. everything feet or everything inches. at least thats the way i took it. google smalians formula. that doc math pulled out three or four formulas for finding the volume of a log

 

[chep]

hey jeff,
no offense taken, considering my grade in forest measurements I am pretty certain that my math is flawed (i did do the numbers on my cell phone...)

however, you and I both have posted the exact same formula i.e. Smaliens formula for volume in cubic feet...

again, by using the basal area multiplier .005454 your number in inches is converted to square feet, then you are multiplying by length in feet. The units are both in feet... This is an accurate measurement of volume. I have used this in the field, calculating pulp volumes on a log landing. It is a little time consuming, but if you havent developed an eye for it yet (like me) then it is the way to go. You can then convert this number to cords by dividing by 128 (cu ft/cord), great for figuring firewood, or pulp...