Abstract:
Studies were carried out on termite and fungal
resistance of the lesser known Albizia malacophylla Ken-
yan wood species. In addition wood dimensional stability,
amount and chemical nature of heartwood extractives was
also evaluated. Wood resistance against white rot tropical
fungi was based on a laboratory soil bed test and subter-
ranean termite resistance in the field according to American
Wood Protection Association: E7-93 (1993) standard.
Wood extractives were subjected to infra-red analysis
using standard laboratory procedures. Albizia malacophylla
heartwood is dimensionally stable (5.5 %) with a less
dimensionally stable sapwood (9.6 %). Heartwood extrac-
tive content is high (9.7 %) in comparison to sapwood
(4.6 %). Albizia malacophylla heartwood is resistant to
fungi (8.1 %) mass loss and very resistant to termites
(4.8 %) mass loss reported after 6 months exposure.
Removal of extractives significantly lowered heartwood
dimensional stability, termite and fungus resistance.
Heartwood extractives were able to inhibit the growth of
fungi under laboratory sterile conditions. Infra-red analysis
of crude heartwood extractives indicated presence of
aldehydes, ketones carbonyl compounds, esters, aromatic,
carboxylic acids and aliphatic carbonyl compounds. Put
together, the nature, amount of heartwood extractives and
wood dimensional stability are at the origin of the found
termite and fungus resistance of A. malacophylla wood.
