Step 1: Understanding the Question:
This question tests knowledge of vegetative propagation methods.
Step 2: Detailed Explanation:
Rooting of cuttings is the ideal method of vegetative propagation for pulpwood species.
It is simple, cost-effective, and produces large numbers of plants.
Grafting (A): Not suitable for pulpwood.
Budding (B): Not suitable for pulpwood.
Air layering (C): Not suitable for large-scale production.
Thus, the correct answer is rooting of cuttings.
Step 3: Final Answer:
Thus, rooting of cuttings is ideal for pulpwood species, which corresponds to option (D).
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