It can grow to heights of 15 m (49 ft) in the tropics.
Like many other mangrove species, it reproduces by vivipary. Seeds
are encased in a fruit, which reveals the germinated seedling when
it falls into the water.
Unlike other mangrove species, it does not grow on prop roots, but
possesses pneumatophores that allow its roots to breathe even when
submerged. It is a hardy species and expels absorbed salt mainly
from its leathery leaves.
The leaves often appear whitish from the salt excreted at night
and on cloudy days. It is often found in its native range with the
red mangrove (Rhizophora mangle) and the white mangrove (Laguncularia
racemosa). White mangroves grow inland from black mangroves which
themselves grow inland from red mangroves. The three species work
together to stabilize the shoreline, provide buffers from storm
surges, trap debris and detritus brought in by tides, and provide
feeding, breeding, and nursery grounds for a great variety of fish,
shellfish, birds, and other wildlife.
The heartwood is dark-brown to black, while the sapwood is
yellow-brown. It has the unusual property of having less dense
heartwood than sapwood. The sapwood sinks in water while the
heartwood floats. The wood is strong, heavy, and hard. The wood is
difficult to work due to its interlocked grain and somewhat
difficult to finish due to its oily texture. Uses include posts,
pilings, charcoal, and fuel. In spite of the fact the tree grows in
a marine environment, the dry wood is subject to attack by marine
borers and termites. Like many species, it contains tannin in the
bark and has been used to tan leather products.