Acacia mangium

Acacia mangium

Origin

Australia and Oceania, including Papua New Guinea.

Ecology

Annual rainfall: 1000-4000mm.

Normal temp range: 17.5-31°C

Altitude range: 0-720m.

Seasonal adaptability: poor drought tolerance.

Soils: pH from 4.5-8.0, grows well on red-yellow podsols, even if heavily eroded. Can tolerate some waterlogging.

Light requirement: strong, as it is a pioneer species.

Other site limitations: performs poorly with less than 1200 mm annual rainfall; does not tolerate strong wind.

Description

Height at maturity: 25-30m.

Diameter at breast height (1.3m) at maturity: 40-60cm.

Form: good, self pruning, straight bole without knots, especially when grown in plantation.

Coppicing ability: only in young stems, poor in old trees.

Growth: in a 13-year old plantation, can reach 23-25m height, 27-30cm diameter at breast height (1.3m).

Other: fixes nitrogen.

Primary advantages

Provides timber and other wood products; can quickly suppress imperata grass (Imperata cylindrica) on degraded acid soils.

Primary disadvantages

Flowers of Acasia Mangium

Some damage has been reported in young stands due to pinhole borers; some damage in nursery due to mildew and molds; wood has a high degree of 'spring' in milling test, a potential defect; heart rot can be a problem in older stands.

Products and yields

Wood products: timber, pulp, plywood, particle board. Yields range from 14m3/ha/yr at 4 years to 44m3/ha/yr at 10 years. Its timber has nice close grain.

Fuelwood: 4800-4900 kcal/kg, produces high quality charcoal.

Fodder: generally considered a poor fodder tree.

Other: shade and ornamental planting.

Propagation

By seed.

Seed treatment

Pour boiling water over seed, 1 part seed to 10 parts water. After 30 seconds to 1 minute remove seeds and place in cold water, then soak overnight, remove, and dry.

Management

Commonly planted at 3x3m spacing. For timber, prune every 6 months, up to the age of 2 years, and thin stands at ages 2, 6 and 10 years. To avoid heart rot, harvest at 5-7 years.

Agroforestry uses

Use in taungya systems. Closes canopy quickly, however, and must be planted at wide spacing (greater then 3x3m) to allow more than one year of annual inter crop.