My family has a big tree with a length of 4 meters and a diameter of 50 cm. How can we calculate its cube? Who will tell us how many cubes it is?

My family has a big tree with a length of 4 meters and a diameter of 50 cm. How can we calculate its cube? Who will tell us how many cubes it is?

You mean volume?
Volume = 400cm × (50cm △ 2) ^ 2 × π = 250000 π cm ^ 3 ≈ 785000cm ^ 3 = 0.785m ^ 3
So the volume is 785000 cubic centimeters, or 0.785 cubic meters

How to cube a tree

Timber length is measured in meters to centimeters, less than 1cm is rounded off; diameter is measured in centimeters, less than 1cm is rounded off; width and thickness are measured in millimeters, less than 1mm is ignored; volume is measured in cubic meters
The size measurement of Chinese fir
1. Length measurement: measure from the big head axe (SAW) to 6cm diameter of the tip end, and carry it by 1m. If it is less than 1m, it shall be rounded off from the tip end, and the length after rounding off shall be the length of inspection ruler. If there are water holes on the big head or small head, the length of water hole measurement shall be removed
2. Diameter measurement: 2.5m away from the big head axe (SAW) mouth, carry it by 2cm. If it is less than 2cm, if it is less than 1cm, round it by 1m, the diameter after entering is the measuring ruler diameter. If it is measured by caliper, the average of long and short diameters after entering is the measuring ruler diameter
3. When the diameter of the stump is normal, the diameter of the stump should be normal
For large head splitting, no matter whether it falls off or not, the thickness (carry size) of the largest remaining section equal to the diameter of the check ruler shall not be counted; if it is less than the diameter of the check ruler, the length equivalent to the diameter of the check ruler shall be deducted, and the length of the check ruler shall be determined again, but the original diameter of the check ruler shall not be changed, After entering the house, it is the diameter of the inspection ruler, and the length of the original inspection ruler remains unchanged; if it does not fall off, it is still the diameter of the original diameter (the diameter after deducting the crack) after entering the house, and the length of the inspection ruler shall be deducted according to the above provisions
Dimensional inspection of logs
1. Length measurement: if the actual length measured is less than the length of the log standard (referred to as length grade), but does not exceed the negative deviation, it shall still be calculated according to the length of the standard; if it exceeds the negative deviation, it shall be calculated according to the length of the next grade
When the saw edge is deviated, the straightness should be taken at the shortest distance between the two ends of the big and small head
If the short diameter of the section is not less than the diameter of the check ruler, the length of the timber shall be measured from the end of the big head. If the diameter is less than the check ruler, the length less than the check ruler shall be removed. If the pocket is cut to be sharp, the timber length shall be measured from the upper edge of the axe
For logs with water hole near the end, the length from the inside of the water hole to the end should be determined, and then the length of the gauge should be determined
2. Diameter measurement: first measure the short diameter through the center of the cross section of the small head, and then measure the long diameter vertically through the center of the short diameter (the thickness of the peeled one). If the short diameter is less than 26 cm, the difference between the long diameter and the short diameter is more than 2 cm, or the short diameter is more than 26 cm, and the difference between the long diameter and the short diameter is more than 4 cm, the average of the long diameter and the short diameter shall be taken as the diameter grade after entering the room; if the difference between the long diameter and the short diameter is less than the above provisions, the diameter grade shall be determined, When the actual size is less than 2cm, it will be increased by 1cm, and those less than 1cm will be discarded
1) When the log small end saw is deflected, the ruler rod should be kept perpendicular to the log length
2) If the log of small head is too small due to water hole, or the log's actual length exceeds the length of inspection ruler, the diameter of inspection ruler is still measured from the end face of small head
3) If the cross section of the small end has outer skin, when the diameter of the inspection ruler must pass through the skin, the ruler rod can be used to horizontally stick to the log surface for inspection
4) The diameter of double heartwood, three heartwood and the middle thin two end expanded logs were measured at the normal part (the thinnest part) of the trunk
5) If the two main bifurcations are in the same length range, the diameter of the inspection ruler shall be measured by the larger section; if they are not in the same length range, the diameter of the inspection ruler shall be measured by the section of the longer main bifurcations. The other bifurcations shall be treated as knots
6) If two logs are connected together, the measuring ruler and rating shall be checked respectively
Dimensional inspection of sawn timber
1. Length measurement: measure the shortest distance between the two ends along the length direction of the timber. If the actual timber length is less than the standard length but does not exceed the negative deviation, it shall still be calculated according to the standard length; if it exceeds the negative deviation limit, it shall be calculated according to the next level length, and the excess part shall not be counted
2. Width and thickness measurement: within the range of timber length, remove 15cm at both ends and any part without blunt edge

How to calculate the cube of a tree

Cross sectional area times tree height