The genus Avicennia contains about 15 species which grow along tropical and subtropical shores. It is commonly included with the family Verbenaceae. The genus Avicennia was dedicated in honor of Abu Sina, Latinized as Avicennia (980–1036 AD), of Bokhara, Arab physician and philosopher.
Avicennia alba baen
Avicennia germinans black mangrove,
black-tree, blackwood, honey mangrove,
mangle blanco, saltbush
Avicennia marina blackwood, mangle nero, mangle prieto, manglecito, parwa
Distribution: This genus grows in pure, dense stands on mud flats along the coast and estuaries, in brackish coastal swamps, and on river banks along lower brackish parts.
The Tree: The tree sometimes reaches a height of 75 ft (23 m), although normally only 25 ft (8 m), with a 2-ft (0.6-m) diameter. Towards the northern end of its limit (Dog Island, Florida) it is shrubby. Black mangroves have long heavy roots which grow extensions (pneumatophores) that aid in gas exchange and coincidentally trap silt to extend the shoreline. Seeds mature and germinate on the tree and then fall to the mud.
General Wood Characteristics: The sapwood of mangrove is wide, yellow–gray to brown–yellow. The heartwood is dark yellow–brown to very dark brown with an oily appearance. The luster is low and the wood has no distinct odor or taste. The grain is irregular and interlocked, and the texture is coarse and uneven. The wood may contain a yellow powdery substance called lapachol. The bole is 20 to 40 ft (6 to 12 m) long and unbutressed, but it is swollen due to numerous pneumatophores (aerial roots). The woods of all species are practically identical, with concentric, anastomosing layers of secondary phloem (bast).
Weighta
Weight
Moisture Specific lb/ft3 kg/m3
content gravity
Green 0.83 74 1,185
12% 0.83 58 929
Ovendry 0.96 NA NA
aReference (59).
Mechanical propertiesa
Property Green Dry
MOE 1.55 106 10.687 GPa 2.09 106 14.411 GPA
lbf/in2 lbf/in2
MOR 11.1 103 76.535 MPa 16.4 103 113.078 MPa
lbf/in2 lbf/in2
C| | 4.94 103 34.061 MPa 8.34 103 57.504 MPa
lbf/in2 lbf/in2
C 1.87 103 12.894 MPa 2.36 103 16.272 MPa
lbf/in2 lbf/in2
WML 12.3 84.809 kJ/m3 17.9 123.421
in-lbf/in3 in-lbf/in3 kJ/m3
Hardness 1,700 lbf 7,561.60 N NA NA
Shear| | 1.37 103 9.446 MPa NA NA MPa
lbf/in2
aReference (59).
Drying and shrinkagea
Percentage of shrinkage
(green to final moisture
content)b
Type of 0% MC 6% MC 20% MC
shrinkage
Tangential 9.7 NA NA
Radial 6.2 NA NA
Volumetric 15.6 NA NA
aThe wood air-dries well; kiln drying
requires a slow
schedule to prevent warping.
bReference (59).
Working Properties: The wood saws well, but it is not easy to work with because of the interlocked grain. It glues well, but nail holes must be prebored to prevent splitting.
Durability: Very susceptible to termite and marine borer attack. Resistance to impregnation variable.
Preservation: No information available at this time.
Uses: Used in the round (poles and posts for netting), underground foundations (pilings), pulp (soda process), fuel, charcoal, tannin from bark.
Toxicity: No information available at this time.
Additional Reading: 4, 14, 29, 45, 55, 68, 74, 80, 55, 66, 68, 74, 79. 28, 29, 42, 43, 44, 48, 50, 55, 56, 68, 72, 73, 74, 79, 92, 97, 102. 74, 75, 77, 99, 106. 101.