Question

The most feasible method of selection of superior trees of forest species in even-aged stand is ________.

• A. The mother tree system of selection
• B. Regression selection system
• C. Subjective grading system of selection
• D. Mass selection with grading system

Hint:

For selecting Plus Trees: use the comparison/grading system in uniform, even-aged plantations, and use regression methods in uneven-aged, natural forests.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Tree improvement programs select phenotypically superior trees (known as Plus Trees) from wild or planted forests to harvest high-quality seeds or vegetative propagules.

Step 2: Detailed Explanation:
In even-aged forest stands (plantations), all trees grew under highly uniform age and site conditions.
To select plus trees in these uniform conditions, the Subjective Grading System of Selection (often implemented as the Comparison Tree Method) is the most feasible and widely adopted approach.
- Under this system, a promising candidate tree is visually identified.
- Its physical parameters (such as height, straightness, and diameter) are then compared and scored against a group of 4 to 5 dominant or co-dominant "comparison trees" growing in its immediate vicinity.
- If the candidate tree scores significantly higher than the local average, it is selected as a Plus Tree.
- The regression selection system is more complex and is used when stands vary significantly in age or site quality.

Step 3: Final Answer:
The subjective grading system (comparison tree method) is the most feasible selection method in even-aged forest stands.