Why is pest/pathogen resistance significant in tree growth?

Why is pest/pathogen resistance significant in tree growth?

• A. Resistant trees grow slower due to energy diverted to defense.
• B. Pathogen resistance promotes faster wood density growth.
• C. Healthy trees are more resilient to diseases and pests, impacting overall forest health.
• D. Pest resistance only affects short-term growth, not long-term health.

Answer: (C)

Pest and pathogen resistance helps keep a tree vigorous by limiting the damage caused by diseases and pests, so the tissues that drive growth—leaves, shoots, and the cambium—can stay healthy and photosynthesize effectively. When trees resist infection, they suffer less defoliation, less heartwood decay, and lower mortality, which preserves the canopy and the tree’s growth potential over time. This resilience translates into steadier wood production and overall forest health, even under outbreak pressure. While defenses do require some energy and resources, the net effect of resistance is to maintain growth and long-term productivity rather than slow growth or only boosting a short-term trait. The other options describe specific or short-term effects that don’t capture how resistance supports sustained growth and stand health.

Pest and pathogen resistance helps keep a tree vigorous by limiting the damage caused by diseases and pests, so the tissues that drive growth—leaves, shoots, and the cambium—can stay healthy and photosynthesize effectively. When trees resist infection, they suffer less defoliation, less heartwood decay, and lower mortality, which preserves the canopy and the tree’s growth potential over time. This resilience translates into steadier wood production and overall forest health, even under outbreak pressure.

While defenses do require some energy and resources, the net effect of resistance is to maintain growth and long-term productivity rather than slow growth or only boosting a short-term trait. The other options describe specific or short-term effects that don’t capture how resistance supports sustained growth and stand health.