Question

The ratio of diameter or girth of a stem at one half its height above the breast-height to the diameter is termed as

• A. Absolute form quotient
• B. Normal form quotient
• C. Form point ratio
• D. Artificial form quotient

Hint:

Remember: "Absolute" form quotient measures the half-height point *above* the breast-height line, whereas "Normal" form quotient uses half of the *total* tree height.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Form quotients are mathematical ratios used in forest mensuration to express the shape and taper of a tree stem.
They relate a stem diameter measured at a specific height along the trunk to the diameter at breast height (DBH, measured at 1.3 meters).

Step 2: Detailed Explanation:
Let us define the different types of form quotients to find the correct term:
1. Absolute Form Quotient ($q_2$): This is defined as the ratio of the diameter of the stem at one-half of its height above breast height to the diameter at breast height (DBH).
Mathematically, it is expressed as:
\[ q_2 = \frac{d_{0.5 \text{ (height above breast height)}}}{d_{1.3}} \]
This quotient is widely used in volume estimation formulas because it excludes the constant 1.3-meter breast height from the height calculation, providing a more consistent measure of stem shape across trees of different heights.
2. Normal Form Quotient ($q_1$): The ratio of the diameter at one-half of the total height of the tree to DBH.
3. Artificial Form Quotient ($q_0$): The ratio of the diameter at any arbitrary height to DBH.
4. Form Point Ratio: The ratio of the height of the center of gravity of the green crown (form point) to the total height of the tree.
Therefore, the ratio described in the question is the Absolute form quotient.

Step 3: Final Answer:
The ratio of stem diameter at one-half its height above breast height to the DBH is termed the Absolute form quotient.