Wednesday, February 25, 2009
Black Mangrove (Avicennia Germinans)
Black Mangroves, larger and taller than the Red and White Mangroves because of their age, they are found upland of the Red Mangroves at higher elevations. These old timers are the most cold tolerant of the three species found in Florida. They can readily be identified by:
Looking at the ground. These trees are surrounded by pneumatophores (prounounced “new-mat-afores”) – stick-like structures (growths) - pointing skyward from the soil surrounding the trunk of the tree. Pneumatophores come from the roots of the Black Mangroves and help the tree to breathe. This species of mangrove generally grows in areas where the soil is saturated with water – without the pneumatophores, which act like a diver’s snorkel, the tree would lack the oxygen it needs to survive.
The bark of a Black Mangrove is dark.
The leaves are shiny dark green on the top, oblong and pointed at the tip. The undersides of the leaves are a dull green color with short dense hairs - glands - which excrete salt – the leaves serve as a back-up system for ridding the Black Mangrove of the salt that has not been excreted by the roots. When early settlers came to Florida they harvested salt from the Black Mangrove leaves.
The seedlings produced by these trees are light green in color and shaped like large coins.
Black Mangrove (Avicennia germinans) has the highest salt tolerant leaves of all the mangroves the leaves and is equipped with special salt-extracting glands. Trees grow to 65 ft (20 m) in height; the long spreading branches are covered by a dark brown bark. Leaves grow in pairs, leathery in texture with a narrow oval shape. The top leaf is dark green and the bottom is pale with hairs often coated with salt. The trees' yellow flowers grow in clusters developing into a green lima bean shaped fruit. Black mangroves have a carpet of short aerial roots or pneumatophores surrounding the base of the tree.
Black Mangoves surrounded by pneumatophores which provide their oxygen when they are submerged by tidal flows.
living nature
4:44 PM
