Question

Which of the followings is not a sub-surface tillage implement?

• A. Tillers with ft-shaped sweeps
• B. Straight blade tiller
• C. Rod-weeder tiller
• D. Lister

Hint:

Sub-surface tillage implements are specifically designed for ______stubble mulching______ to prevent wind and water erosion.
They never invert the soil, whereas a ______Lister______ is a primary surface-shaping tool that creates pronounced ridges and furrows.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
Tillage operations are classified based on the depth and nature of soil disturbance.
Sub-surface tillage implements are designed to cut beneath the soil surface to sever weed roots and loosen the soil without inverting it, thereby keeping crop residues on the surface for erosion control.

Step 2: Detailed Explanation:
Let us analyze the function of each implement:
1. Sweeps (ft-shaped sweeps) (A): These are V-shaped blades designed to run parallel to the soil surface, cutting weed roots just below the surface while leaving residues undisturbed. (Sub-surface implement)
2. Straight blade tillers (B): These are flat blades designed to slice through the soil subsurface to shatter hardpans and kill weeds without soil inversion. (Sub-surface implement)
3. Rod-weeder tillers (C): These consist of a rotating square rod driven under the soil surface. As the rod rotates backwards, it pulls up weed roots and deposits them on the surface while maintaining a mulch cover. (Sub-surface implement)
4. Lister (D): A lister (or lister-plow) is a double-moldboard plow. It operates on the soil surface to open deep furrows and throw soil to both sides, forming ridges.
Because it actively inverts, moves, and shapes the surface soil, it is a surface-tillage and bed-forming implement, not a sub-surface tillage tool.

Step 3: Final Answer:
The implement that is not a sub-surface tillage tool is the Lister, which corresponds to option (D).