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Allocasuarina littoralis
black sheoak
Overview
Allocasuarina littoralis is an upright, narrow-crowned tree in the family Casuarinaceae, growing 16-33 feet (5-10 m) tall with dark, furrowed bark. In place of broad leaves it carries slender, drooping green branchlets that are jointed and grooved, taking over photosynthesis, while the true leaves are reduced to tiny scales in whorls at each joint. The tree is dioecious, with male and female flowers on separate plants. Male trees turn rusty brown in season as the branchlet tips release pollen, while female trees bear small red flowers that develop into woody, cylindrical cones 0.5-1.2 inches (1.5-3 cm) long holding winged seeds. It grows in open forest, woodland, and coastal scrub along eastern Australia, from Queensland to Tasmania, on sandy and gravelly soils. As a member of its family it fixes nitrogen through root nodules and tolerates poor, low-nutrient ground. It withstands drought, wind, salt spray, and light frost once established. The fallen branchlets form a dense litter that suppresses other plants beneath the canopy. Seed is held in the cones and released after fire or branch death. The narrow form and shedding branchlet litter limit underplanting.
Native Range
Allocasuarina littoralis is native to eastern Australia, from Queensland through New South Wales and Victoria to Tasmania. It grows in open forest, woodland, and coastal scrub on sandy and gravelly soils, often near the coast.Suggested Uses
Grown as a screen, windbreak, and habitat tree in native, coastal, and revegetation plantings, where the seed feeds black cockatoos and the canopy shelters birds. It suits poor, sandy, and salt-exposed sites. The narrow crown suits boundaries and shelterbelts.How to Identify
Appearance
Size & Dimensions
Height16' - 33'
Width/Spread8' - 16'
Bloom Information
Male trees release pollen mainly in autumn and winter, turning a rusty brown, while female trees carry small red flowers around the same time. Flowers are wind-pollinated and lack petals. Woody cones develop on female trees and persist for months, releasing seed gradually.
Detailed Descriptions
Flower Description
rusty brown (male), red (female)Foliage Description
greenGrowing Conditions
Sun Requirements
Requires 6-12 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight