By Lucía Rodríguez Sánchez, Director of Research, Finca Leola S.A.

Terminalia amazonia

Family: Combretaceae

Common name: roble coral, amarillón

Comercial name: bullywood

Roble coral’s wood is heavy or very heavy, with green weight between 1020 and 1100 kg/m3, and 50 to 80 percent moisture content; basic specific weight is 0.68. Based on its physical and mechanical properties, the timber is of high or excellent quality. Its natural durability and fungal resistance could vary with origin, and it has moderate resistance to termite attack.

The timber is commonly used in heavy general interior and exterior construction, cabinetwork, floors (parquet), decorative veneers, bridge foundations, and boats. According to Flores¹ (1994), drying is moderately difficult, but it can vary with wood origin, too. During drying, the wood may show cracks, moderate fissures, and slight twisting.

In its green state, the sapwood is grayish yellow, and the heartwood is darker. When dry, the sapwood turns orange or yellowish, and the heartwood becomes reddish yellow, light yellowish brown, or yellowish olive with darker reddish or dark brown stripes. The wood tends to oxidize rapidly when it has been exposed to air and light (Flores, 1994). The wood has an interlocked grain, medium texture, and high luster on radial planes, but it is regular on tangential planes, which makes it difficult to finish. Radial cuts are made parallel to the long axis, through the center; the grain pattern is a series of parallel lines. Tangential cuts are parallel to the long axis, anywhere but through the center; the grain pattern is wavy and variable, not all parallel. The lines and veins resulting from both types of cuts make this wood very attractive.

Terminalia amazonia is the most distributed neotropical species of this genus. It has a wide geographic distribution extending from the Gulf of Mexico in the Atlantic watershed to the Guyanas in South America, including the Antilles (Trinidad and Tobago). In Costa Rica it grows in humid forest on both the northern and southern slopes of the central range, but its frequency has been reduced due to intensive tree cutting.

It is a tall tree and a dominant species in the evergreen rainforest and very wet forest on both Costa Rica’s watersheds. It can reach heights above 50 m (164 feet), and in some forests, up to 70 m (230 feet) and reaches 120 to 150 cm (4 to 5 feet) DBH. Usually it has a straight trunk, frequently grooved in the basal third. It has conspicuous buttresses (easy to observe), which are longer and wider when the species grows in swampy areas. The bark is quite thin, dull, and grayish brown or grayish yellow colored and exfoliates medium-size flecking plates. It is a helophyte species (grows in full sunlight) and regenerates easily in open areas, forest edges, and pasturelands. It grows at altitudes between 20 and 1200 m (66 and 3937 feet) with annual rainfall above 1500 mm (60 inches), and commonly as a riparian (along the rivers and creeks). The species grows well in many different soil types, but seems to do better on clay soils.

Blooming occurs between February and April. The fruit ripens between March and May; most flowers develop a fruit, but many fruits lack seeds, so people usually report lower germination rates. The immature fruits are depredated by parrots and parakeet bands.

Experimental plots of roble coral in the northern zone of Costa Rica with spacing that varies from 2 x 2 m (6.6 x 6.6 feet) and 4 x 4 m (13.12 x 13.12 feet) at three years of age are achieving up to 85% survival, with an average growth of 5 m (16.5 feet) and 5.8 cm (2.28 inches) DBH. This species is believed to have a great future in reforestation programs in the northern and southern zones of Costa Rica.

¹Flores, E. 1994a. Arboles y Semillas del Neotropico. Vol. 3, Nº1. San Jose, Museo Nacional de Costa Rica.