Three Introduced Species
The commercial tree species most frequently planted in the Orinoco River basin are from Australia, Acacia mangium and Eucalyptus pellita. Both are fast growing hardwoods that adapt well to local climatic conditions, tolerate acidic soils and bring other benefits to a forestry project. For example, Acacia mangium is a nitrogen and carbon fixing tree, important for restoring poor soils. Eucalyptus pellita is a good tree for erosion control and helps maintain ground water levels. Both trees are used for lumber and other general carpentry needs, but also have very high kilocalorie values, making them excellent biomass trees for energy uses. Eucalyptus pellita is marketed internationally as red mahogany, but can also be used for pulp and paper. Acacia mangium is often used for decks, furniture and posts. The third species, Pinus caribaea or Caribbean Pine is from Honduras. Its wood has all the qualities of other pine species and is excellent for construction or general carpentry. Growth cycles are 10 years for Acacia mangium, 12 to 15 years for Eucalyptus pellita and 20 years for Pinus caribaea.
How are the trees cultivated?
Introduced species are planted in grids of 2.8 X 2.8 meters (9' X 9' feet), with 1,270 trees planted per hectare (2.47 acres). Acacia mangium requires formative pruning, in order to have a single main trunk and in order to avoid a lot of knots in the wood. In contrast Eucalyptus pellita is self-pruning, with a straight trunk and lower branches simply dropping off. Caribbean pine can benefit from pruning of the lower branches, to ensure less knots in the trunk. None of the 3 species like wet soils, so it is important to plant in areas with good soil drainage. Acacia mangium can pose a challenge in soils with high clay content or silty soils, as the tree has a very shallow root system and can topple over in high winds. The trees are planted in 5 to 10 hectare lots, with different species in different lots, to avoid a monoculture. We also plant other species in neighbouring lots. All lots have 20 meter wide fire breaks and controls, which are maintained every year. A small tractor is used for maintenance work in the lots, as it does not put pressure on the root systems of the trees. Acacia mangium has extra-floral nectar all year, which means we have beehives in all Acacia cultivations, with the bees doing local pollinization. One hectare of Acacia mangium will produce 100 KG of excellent honey per year. All of our trees are planted and fertilized using natural fertilizers and sustainable practices.