Brazilian rosewood  (Dalbergia nigra)

The Brazilian rosewood is classified as Vulnerable (VU) on the IUCN Red List (1) and listed on Appendix I of CITES (3).

One of the most highly prized woods in Brazil, the timber of the Brazilian rosewood (Dalbergia nigra) has been harvested since colonial times to construct high quality furniture and musical instruments (1). The timber of this species is particularly precious as it is not only extremely strong, but also highly resistant to insect attack (4). 

The branches of the Brazilian rosewood are dark and roundish and grow in a distinct zig-zag pattern. The leaves bear 12 to 18 alternate leaflets, and the flowers are pale, violet-scented, and pea-like in shape (2).

Occurring only in the Atlantic coastal forests of Brazil, populations of the Brazilian rosewood are scattered between southern Bahia and Minas Gerais, with the highest concentrations found on rich soils between southern Bahia and northern Espírito Santo (1) (2) (5). 

The Brazilian rosewood grows in wet (hygrophilous) forests on rich soils, especially where the soil consists of clay and loam (a mix of sand, silt and clay) with good drainage. It grows across a range of climatic conditions that includes tropical lowlands and sub-montane rainforests (1) (2) (5). 

The Brazilian rosewood grows as a medium-sized tree in semi-deciduous tropical forests in Minas Gerais, but tends to be larger elsewhere. It is now rare in undisturbed forests, and is more common as a small tree in secondary growth and pastures, as it regenerates well from stumps. The Brazilian rosewood is also often cultivated in experiment stations, parks and urban areas, either as an ornamental tree or for its economic value (5).

Very little is known about the ecology and reproduction of the Brazilian rosewood, but it is known to have a short flowering period between November and December and a long fruiting period between January and September. The flowers are pollinated by bees and the seeds are dispersed by the wind (6). Germination is determined by temperature, with the optimal temperature being 30.5 degrees Celsius, although the seeds can germinate at any temperature between 10 degrees Celsius and 45 degrees Celsius (7).

The Brazilian rosewood has been harvested since colonial times to make high-quality furniture and musical instruments. It is now regarded as one of the most valuable trees in Brazil, for its timber and also for its oils and resins (1) (2). 

However, past rates of deforestation have been extremely high, and trees with thick trunks are now rare as most have been logged (1) (2). Populations are also now highly fragmented across its extensive range. Regeneration rates among existing populations are also poor, possibly because the seeds of the few remaining fruiting trees are heavily predated by rodents (1). Overexploitation has also reduced the Brazilian rosewood’s genetic diversity, with populations in areas of high human disturbance having low genetic variation (6) (8).

As a result of its severely depleted and declining populations, in 1992 the Brazilian rosewood became the first tree species to be listed on Appendix I of the Convention on International Trade in Endangered Species (CITES), so prohibiting any international trade in this species’ products (3) (7). 

Further recommended conservation measures for the Brazilian rosewood include greater protection for forest remnants with high genetic diversity, such as those in northeast Minas Gerais state (8). At present there is some small-scale cultivation of this species, but plantations may also need to be established if it is to be successfully conserved (2).

To find out more about the conservation of threatened tree species, see:

• Global Trees Campaign:
  http://www.globaltrees.org/
• Forest Stewardship Council:
  http://www.fsc.org/

For more information on conservation projects in the Atlantic forest, see:

• Conservation International – Atlantic forest:
  http://www.biodiversityhotspots.org/xp/hotspots/atlantic_forest/Pages/default.aspx
• WWF – Atlantic forest:
  http://www.wwf.org.uk/what_we_do/safeguarding_the_natural_world/forests/forest_work/atlantic_forest/