I-4 Measuring fresh weight of each organ of a sample tree

Fig 2 Clearing small branches from boughs and separating them in to twigs and leaves, then weighing them by various spring scales

1) Of all the boughs cleared off the trunk, the dead boughs must be separated from the live ones.

2) All the live boughs, then, shall be cleared off of all the small branches (twigs and leaves). The cleared boughs and the small branches shall each be collected onto a separate vinyl sheet (Fig2).

Pic5 3) The small branches then shall be stripped off of all the leaves. The leaves and the twigs shall be collected separately on the vinyl sheets for weighing (Fig2).

(Pic Stripping leaves from twigs. )

4) The cleared boughs must be weighed, and noted in the field note (appendix 3). It is advisable to wrap the boughs in a vinyl sheet or bundle them with a rope for weighing by a spring scale. The tare such as the vinyl sheet or the rope must be weighed and noted in the field note as well.

Pic6 5) The twigs shall be weighed. It is advisable to weigh them in appropriate vinyl bags or wrapped up in a vinyl sheet. The tare such as the bags or the sheet must be weighed and noted in the field note as in the above.

(Pic Weighing cleared-boughs. Boughs are wrapped in a vinyl sheet.)

6) Lastly, all the leaves must be weighed, and noted in the field note.
The leaves shall be weighted in appropriate bags or wrapped up in a sheet. The tare must be weighed and noted in the field note (appendix 3) as in the above.
If the quantity of small branches is large, estimation by samples can be made. Firstly, weigh the entire small branches of a sample tree. Then take 1/3 to 1/4 of the small branches as a sample that would represent the entire sample tree, and separate them to twigs and leaves. The weighing shall follow the same procedure as in the above.
The ratio of the weight of twigs and that of leaves can be calculated as follows. The entire weight of twigs and leaves of the tree can be estimated from this ratio and the weight of entire small branches.


where, EWtwig, EWleaf, EWsbranch each stands respectively for the entire weight of twigs, that of leaves and of small branches of the sample tree. SWtwig and SWleaf indicate the weight of the samples of twigs and of leaves respectively.

I-5 Collecting samples for dry weight estimate
Dry weight estimate, that is required to work out the volume of carbon estimate of biomass, can be made by samples.
Pic7 Samples for dry weight estimate shall be collected from the sample tree used for fresh weight measurement in the above I-4. The sample of the trunk, bark, boughs, twigs, and leaves shall be collected. It is advisable to collect each of them into separate paper bags for drying and weighing. The sample tree number and the organ name must be indicated on each bag. The samples collected in the bags must be weighed immediately for the fresh weight and be noted in the field note (appendix 4). The weight of the tare must be weighed and noted in the field note as well. It is strongly advisable to use a balance with high accuracy such as an electronic balance.

(Pic Putting samples into paper bags for drying and weighing them with the electronig balance.)

1) Boughs
Samples must be selected from boughs of various diameters and be cut into 10cm pieces in length. The cut pieces must be put into a paper bag with the sample tree number clearly indicated. The desirable weight of a sample is around 0.5kg to 1.0kg.

2) Twigs
Samples must be cut into 10cm pieces in length and be put into a paper bag. The desirable weight of the samples be around 0.3kg to 0.5kg.

3) Leaves
The leaves must be put into paper bags. The desirable weight is 0.3kg to 0.5kg.

4) Trunks and barks
A disk of 2.0cm to 4.0cm thickness must be cut out of each log marked with "0.3-1.3", "1.3-3.3" and so on indicating its position of the felled trunk. The barks must be removed from each disk. The disks without the barks and the barks must be put into different paper bags with the sample tree number and the log position clearly indicated.
Tools: Small saws, pruning shears, ground sheets in vinyl, large and small paper bags, small plastic bags, spring scales, an electronic balance

Samples for LAI (Leaf Area Index) can be collected here. Around 10 leaves must be taken to the laboratory in plastic bags for working out the estimate of LAI. The leaves must be carried with care so that they will not be disfigured for working out the size of each leaf.

I-6 Drying samples
The samples must be dried in circulating oven. The samples of the trunks (the disks of the above item I-5-4) and of the boughs of the above item I-5-1) must be dried in a circulating oven at the temperature kept at 80 to 90 degrees centigrade for 4days (96hrs). The samples of the barks, twigs and leaves must be dried for two days (48hrs). The dry weight of the samples must be weighed and noted in the field note (appendix 4) then calculate the moisture contents of the each organ.

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