The response of red mangrove, Rhizophora mangle L., to wounding was studied Young mangrove seedling hypocotyls were wounded. Wound periderm development was documented with both light microscopy and scanning electron microscopy. The separation of necrotic tissue from the living tissue by a closing layer occurred in 17 d, and the development of wound periderm enclosing the wound was observed in 52 d. Brachysclereids developed in the wound periderm, and vascular tissue proliferated near the wound. Wound periderm development compartmentalized wounds and thus may prevent the spread of pathogens from the wounded tissues to the adjacent living tissues.