Paradise Tree

Native to tropical America, distributed from southern Florida through the Caribbean, Central America, and throughout tropical South America to Bolivia and southern Brazil. The species occurs in lowland tropical wet and moist forests from sea level to approximately 1,200 m elevation. It is particularly common in the Guianas, the Amazon Basin, and the Atlantic forests of Brazil. The genus Simarouba comprises about 6 species, all native to the Neotropics, with S. amara being the most widespread and economically important.

A medium to large canopy tree: • Height: 20-35 m with trunk diameter 40-80 cm, often with small buttresses. • Bark: Gray to brown, relatively smooth with lenticels, extremely bitter tasting due to quassinoid compounds. • Leaves: Large, compound, imparipinnate, 30-60 cm long with 7-15 ovate to lanceolate leaflets, each 8-18 cm long, glossy dark green above and paler beneath. • Flowers: Small, yellowish-green to cream, unisexual (dioecious), borne in large open panicles 20-40 cm long. • Fruit: Small ellipsoid drupes 1.5-2 cm long, green ripening to dark purple or nearly black, each containing a single seed. • Wood: Heartwood pale yellow to light brown, moderately dense (specific gravity 0.45-0.55), straight-grained and easy to work.

An important canopy component of neotropical forests: • Phenology: Evergreen to semi-deciduous, typically flowering during the dry season and fruiting during the early wet season. • Pollination: Small flowers attract a variety of insect pollinators including bees, flies, and beetles. • Seed dispersal: Fleshy purple-black drupes are consumed by birds (especially toucans, trogons, and manakins) and bats that disperse seeds throughout the forest. • Chemical defense: All plant parts contain bitter quassinoids (particularly simalikalactone D) that deter herbivory by insects and mammals. • Habitat: Prefers well-drained sites on ridges and upper slopes in primary forest, less common in floodplain habitats. • Regeneration: Seedlings are moderately shade-tolerant and can persist in the understory for years awaiting canopy gaps.

Listed as Least Concern by IUCN due to its broad distribution across tropical America. However: • Selective logging for timber has reduced populations in some areas, particularly in Central America and the Brazilian Atlantic Forest. • The Brazilian Atlantic Forest, where the species occurs, has been reduced to approximately 12% of its original extent. • Conservation benefits from the species' occurrence in several large protected areas including Manu National Park (Peru) and Central Suriname Nature Reserve. • Sustainable harvest programs are being developed in parts of its range. • The species' medicinal value provides an incentive for conservation through sustainable use.

Cultivation is straightforward: • Propagation: Seeds germinate within 15-30 days without pretreatment; fresh seeds have higher viability. • Growth rate: Moderate, approximately 1-2 m/year in good conditions. • Soil: Prefers well-drained, slightly acidic to neutral soils; tolerates poor soils. • Light: Seedlings tolerate shade; saplings and mature trees require full sun. • Spacing: 6-8 m in plantation settings. • Suitability: Excellent species for reforestation and agroforestry systems in the tropics due to its moderate growth and nitrogen-rich leaf litter. • Drought tolerance: Moderate once established. • Can be grown as an ornamental shade tree in tropical landscapes for its attractive pinnate foliage.

Multiple applications: • Timber: Known as marupa or simarouba in the lumber trade; used for furniture, interior construction, plywood, and paper pulp. • Medicine: Bark extracts contain quassinoids (simalikalactone D, glaucarubinone) with demonstrated antimalarial, anti-inflammatory, amoebicidal, and anticancer properties. Traditional uses include treating dysentery, malaria, fever, and intestinal parasites. • Agroforestry: Excellent shade tree for coffee and cacao plantations. • Oil: Seeds contain 40-50% edible oil used for cooking and soap-making in parts of South America. • Wildlife: Fruits are an important food source for canopy birds and bats. • Reforestation: Used extensively in tropical reforestation programs in Brazil and Central America.