Agroforestree Database

Local names:
 Creole (doliv,fwenn,bwa blan,bwa fwenn), English (simarouba,princess tree,bitter ash,bitter damson), French (quinquina d’Europe,bois amer,bois blanc,bois Frêne,bois négresse), Spanish (acajou blanc,daguillo,gavilan,juan primero,laguilla olivio,palo amarg

The mature tree attains a height of 25-27 m and a stem diameter of 40-50 cm, often with a clear, cylindrical bole to 9 m. The crown is narrow, with a width averaging 4-6 m, and a crown width-to-dbh ratio of 22:25. Simarouba glauca develops a shallow root system often suitable to mountain soils.

Leaves dark green above; oblong, and often notched or smooth at the apex.

The specific name ‘glauca’ means covered with a bloom, which refers to the bluish-green foliage; it is derived from the Greek work ‘glaukos’ (bluish).

Ecology

S. glauca is shade tolerant and occurs as an understorey tree, particularly under the canopy of large fruit trees where birds perch and deposit the seeds. It is found as an associated species of the subtropical moist forest, sharing a position with other common trees of the home and humid perennial gardens, such as mango (Mangifera indica), royal palm (Roystonea borinquena), avocado (Persea americana) and plantain (Musa x paridisiaca). The species does poorly on severely degraded sites and approaches the limits of its optimal range in regions receiving less than 1200 mm. It is resistant to storms and drought.

Native range
Bahamas, Costa Rica, Cuba, El Salvador, Guatemala, Haiti, Honduras, Jamaica, Mexico, Puerto Rico, United States of America

Tree management

If the objective of managing the trees is seed production, male plants should be eliminated and replaced with bisexual ones. For saw log production, pruning lateral branches is essential to obtain boles clear of branches. Pruning also allows flexibility in growing the tree as part of the upperstorey of a perennial garden or in pure, dense stands of a woodlot. At least 2 branch storeys or whorls must be left when pruning to avoid impairing growth rates. Plantations have been reported to resist storms and drought and in India are favoured over cashew (Anacardium occidentale) for such reasons. The species coppices, though not vigorously. The bitter leaves are avoided by livestock, an advantage for seedlings that develop slowly on tough sites. Height growth has never been observed to exceed 2 m/year. The fastest growth measured in Haiti was 1.8 m/year, with the average close to 1 m/year.

The high oil content of the seed causes it to lose viability after a couple of months when it is stored at ambient conditions. Drying seed to mc below 10% and storing in airtight containers improves seed longevity. There are 1600-1800 seeds/kg.

S. glauca is shade tolerant and occurs as an understorey tree, particularly under the canopy of large fruit trees where birds perch and deposit the seeds. It is found as an associated species of the subtropical moist forest, sharing a position with other common trees of the home and humid perennial gardens, such as mango (Mangifera indica), royal palm (Roystonea borinquena), avocado (Persea americana) and plantain (Musa x paridisiaca). The species does poorly on severely degraded sites and approaches the limits of its optimal range in regions receiving less than 1200 mm. It is resistant to storms and drought.

S. glauca usually regenerates naturally, when birds drop the seed after eating the sweet pulp. However, farmers occasionally transplant volunteer seedlings or sow seeds in new locations. It is preferred to sow fresh seed within a month following harvest, and prepare the seed by cracking the endocarp to overcome dormancy barriers exhibited as a result of the hard seed coat. Emergents have a tendency to loop or lie on their sides. Sowing the seed on its side partially overcomes this problem; extra seed is sown in germination beds for replacing deformed seedlings. Sun scalding is a problem when seedlings are moved directly from shade to the sun. This problem is avoided if the seedlings are conditioned properly. Approximately 12 weeks are required to raise seedlings in the rigid cell containers, with the initial 4 weeks in the shade and the seedlings being hardened off in the final month. 

Nursery beds for stumps or bare-root seedlings are a recent development of agroforestry and forestry projects in Haiti and are better suited for local production of seedlings where natural regeneration is scarce. Stumps or balled seedlings are planted out during the rainy season when root collar diameter reaches 7-10 mm. Vegetative techniques include air-layering, cuttings and grafting.

Poison:  The residual cake left after processing the crude fat from the seed contains a toxin. 

  The edible parts of S. glauca are the fruit and the oil from its seed.

Apiculture:  During the flowering season, S. glauca is visited by swarms of bees and considered an important honey plant.

Timber:  S. glauca wood has a moderate density, is soft and easy to work, grows fast and is broadly adapted with an ample natural regeneration. These factors ensure an adequate supply for local wood industries, thus making it a popular wood for house construction and common furniture for the local farmers. The creamy white colour of the heartwood is barely distinguishable from the sapwood. The wood is light (specific gravity 0.38) and soft, with strength properties normal for a wood its density. It is commonly reported in Haiti and India that the wood has a tendency to split during sawing. Seasoning with prolonged weather exposure causes severe surface and end splitting. The wood is generally sawn into planks that are easy to work as a general utility wood. Staining fungi that attack the wood actually enhance its appearance for decorative uses. The wood industry in Central America uses the species in match manufacture, plywood core, veneer, wood chips and lumber.

Lipids:  Seed of S. glauca yield oil. The aceituno fat is also used for soap manufacture in India, where plantations have been established for its commercial production.

Medicine:  All parts of the tree are used for medicinal purposes. The bark is taken as a decoction or tea for diarrhoea and fever. Leaves are used for rheumatism or are applied in the form of a lotion for body pain, bruises or skin itch.

Soil improver:  The press cake resulting from the milling operation is used as an organic fertilizer and has given good results on coffee, sugarcane, cotton and maize.

Intercropping:  The fast, straight growth and wide adaptability on shallow soils of Haitian mountains combine to make this tree an attractive choice for agroforestry.