Cambium miners disrupt which part of the tree?

Cambium miners disrupt which part of the tree?

• A. The heartwood
• B. The cambium or growth layer
• C. The outer bark only
• D. The resin canals

Answer: (B)

The key idea is that cambium is the growth layer of the tree. This thin, living tissue sits between the wood (inside) and the bark (outside) and is responsible for producing new xylem toward the inside and new phloem toward the outside, which drives radial growth. When cambium miners disrupt this layer, they interfere with the tree’s ability to form new cells, effectively slowing or stopping growth around the circumference and potentially girdling the tree if the damage is widespread. That disruption directly impacts how the tree transports water and nutrients and maintains its structure, which is why the cambium or growth layer is the correct focus. Heartwood is older, nonconductive interior wood; outer bark is the protective exterior; resin canals are defensive structures—not the active growth tissue that cambium miners target.

The key idea is that cambium is the growth layer of the tree. This thin, living tissue sits between the wood (inside) and the bark (outside) and is responsible for producing new xylem toward the inside and new phloem toward the outside, which drives radial growth. When cambium miners disrupt this layer, they interfere with the tree’s ability to form new cells, effectively slowing or stopping growth around the circumference and potentially girdling the tree if the damage is widespread. That disruption directly impacts how the tree transports water and nutrients and maintains its structure, which is why the cambium or growth layer is the correct focus. Heartwood is older, nonconductive interior wood; outer bark is the protective exterior; resin canals are defensive structures—not the active growth tissue that cambium miners target.