What are cankers?

What are cankers?

• A. Growth bursts on the trunk.
• B. Localized necrotic lesions primarily caused by fungi, often associated with rot.
• C. Exudates from the bark.
• D. Branches that fail to develop.

Answer: (B)

Cankers are localized necrotic lesions on the bark and underlying wood. They typically develop after wounding or infection, with fungi (and sometimes bacteria) colonizing the cambial region just beneath the bark. The result is dead tissue that forms a sunken area, often with rot in the adjacent wood. Because the necrotic tissue can expand and encircle the stem or branch, it can disrupt the tree’s water and nutrient transport. This description—localized dead tissue on trunks or branches, usually caused by fungal infection and often associated with rot—captures what cankers are. The other options describe growth spurts, sap exudation, or branches that don’t develop, which are different phenomena.

Cankers are localized necrotic lesions on the bark and underlying wood. They typically develop after wounding or infection, with fungi (and sometimes bacteria) colonizing the cambial region just beneath the bark. The result is dead tissue that forms a sunken area, often with rot in the adjacent wood. Because the necrotic tissue can expand and encircle the stem or branch, it can disrupt the tree’s water and nutrient transport. This description—localized dead tissue on trunks or branches, usually caused by fungal infection and often associated with rot—captures what cankers are. The other options describe growth spurts, sap exudation, or branches that don’t develop, which are different phenomena.