I established a test plot today. I plan to measure both biomass of the plot in general and the diameter and height of a currently healthy White Ash, to try and understand forest growth. It is a hobby I have taken up, to ensure that my skills stay honed, for the next time I am out in the field.

**Biomass and Carbon Sequestration:**

It has long been known that plants take in CO2 gas, during photosynthesis, to create carbohydrates for the plant to use. Plants also release CO2 during respiration, but the net uptake exceeds that released during respiration, meaning that the plant stores carbon. It is said that up to 50% of a tree’s mass is carbon, and much of that carbon is stored in the extensive root systems. In order to calculate how much carbon a tree contains, first we must find out the total mass of the tree.

**Mass=Volume*Density**, so to find the biomass of a tree, we must first find the volume of the tree.

Since, for our purposes, trees are cones, we would find Volume with the following formula (many of you remember from geometry).

**Volume=1/3*Basal Area*Height**

**Height** can be found by taking a tape measure, and by standing back approximately as far as the tree is high, you use the tape measure to find the point on the tree that is about 10% of the tree. You then measure the height of that point and multiply by 10.

**Basal area** is found by first measuring the diameter of the tree at breast height, which is considered to be 1.6 meters. Then you plug that into the following equation (DBH/200)² * π.

You now have volume, but you still need density. To find density, you first must identify the tree. You can then use the following site to find the density (http://www.csudh.edu/oliver/chemdata/woods.htm).

Finally your biomass equations should go as follows: Biomass(kg)=stem volume(m³)*density(kg)+40% of the answer to factor in other biomass such as roots and leaves.

If for instance, you take the White Ash from the test plot, which has a volume of 17.8 m³ and has a density of 650 Kg/m³, you get a stem mass of 11,570 Kg.

11,570*.4 = 4,628.

**Total mass** = 16,198 Kg or 16.2 tons of biomass.

About half of that is made up of carbon, so about **8 tons of carbon**.

For the entire wood lot, the equation looks like this.

126(m2/Ha) * 15.24(m) * 1/3=640(m3/Ha)

640(m3/Ha) * .65 (t/Ha)=416(t/Ha) * .4=166.4

416+166.4=**582.4(t/Ha) of Biomass**** of which 291.2 tons are made up of carbon.
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Just in my little wood lot (about 2.5 acres, or 1 hectare) alone, the trees are sequestering nearly 300 tons of carbon. When we consider carbon’s role in the greenhouse effect, (being an unstable element, it releases heat to stabilize, thus, the more carbon in the atmosphere the more warming will be expected) we can see that even a small forest can help to make a big difference.

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