In trunk implantation, the head of the implant device is placed in which tissue layer to promote wound closure?

• A. In the cambium (growth layer)
• B. In the xylem center
• C. On the bark surface
• D. In the phloem tube

Answer: (A)

Wound closure is driven by the plant’s meristematic growth, so placing the implant head in the cambium—the living growth layer between bark and wood—provides access to actively dividing cells that form new vascular tissue and callus to seal the wound. This cambial tissue can generate the necessary xylem and phloem to bridge the wound and integrate the implant with the plant’s vascular system, promoting faster and more reliable closure. The center of the xylem is typically non-living heartwood, so placing there wouldn’t support healing. The bark surface is outside the internal healing processes, and phloem tissue alone isn’t the best site for initiating the growth needed to close a deep wound; cambium is the key source of new growth for wound repair.