The genus Myroxylon was originally described in 1753 by Linnaeus, such description was made using a specimen collected in the province of Cartagena, and named it Toluifera balsamum. The genus Myroxylon was first established by Linnaeus filius in 1781, when he described Myroxylon peruiferum based on a specimen collected by Mutis in South America. Latex from Myroxylon trees is the source of Balsam of Peru and Tolu balsam and composition. Some authors recognize infra-specific taxa based, mainly, in their balsam phytochemistry; while other authors do not recognize such categories. There are reports of differences in composition of balsams obtained from M. balsamum, M. balsamum, and M. peruiferum. It is in the flowering plant familyFabaceae. There are two species, M. balsamum and M. peruiferum.
Distribution
Myroxylon is a genus of tree grown in Central America and South America. Myroxylon balsamum occurs in Central America, and northern and western South America, it is fairly common in tropical forest at 200–690 m altitude. In Peru and Brazil this species is mostly associated with rivers, and sometimes grows on lateritic soil. It is found in remnants of mesophillous forest. At present it is considered as being of least concern according to CITES classification. Myroxylon peruiferum is disjunctly distributed in the Americas, from Mexico to northern Argentina and southern Brazil, though it has a wide distribution, it is not abundant within its area of occurrence. It is found in remnants of mesophillous forest and dry habitats at 540–2000 m elevation. It is considered to be Near Threatened, according to CITES classification.
The tree
The trees are large, growing to tall, with evergreenpinnateleaves long, with 5–13 leaflets. The flowers are white with yellow stamens, produced in racemes. The fruit is a pod long, containing a single seed. The tree is often called Quina or Balsamo, Tolu in Colombia, Quina quina in Argentina, and sometimes Santos Mahogany or Cabreuva in the lumber trade. Members of this genus produce hydroxypipecolic acids in their leaves. The wood is dark brown, with a deep red heartwood. Natural oils grant it excellent decay resistance. In fact, it is also resistant to preservative treatment. Its specific gravity is 0.74–0.81. With regard to woodworking, the tree is moderately difficult to work but can be finished with a high natural polish; it tends to cause some tool dulling.
Invasive species
The balsam tree can become a highly invasive species when introduced into tropical countries where it is not native. In Sri Lanka, it has overgrown several hectares of the Udawatta Kele Sanctuary and is rapidly spreading there. In this Sri Lankanrain forest, Myroxylon seeds sprout in very high numbers due to tolerating more diverse light conditions than native species and due to the absence of natural enemies such as diseases and insects. This has given rise to dense stands of young trees where no other vegetation can grow, causing severe ecological disruption, i.e., the disappearance of local, native plant species and consequently of the animals and insects that feed on these. The tree has also been introduced to several Pacific islands such as Fiji and to Indonesia, and is a potential ecological threat there.
