Allocasuarina muelleriana
slaty sheoak
Overview
Allocasuarina muelleriana is a shrub growing 3-13 feet (1-4 m) tall, with slender, drooping to erect green branchlets that carry out photosynthesis in place of true leaves. The leaves are reduced to small scales arranged in whorls of 9-12 around the jointed branchlets, which are 0.01-0.02 inch (0.3-0.5 mm) wide and give the plant a wiry, needle-like appearance. The species is usually dioecious, with separate male and female plants; male plants bear brownish flower spikes at the branchlet tips, and female plants bear small red flower heads that develop into woody cones. The cones are cylindrical, 0.5-1.2 inches (12-30 mm) long, holding winged seeds released after the cones dry or after fire. Flowering occurs mainly in autumn and winter. The plant grows on a woody base, tolerates poor sandy and rocky soils, and resprouts from the base after fire in many populations. Growth is slow to moderate. Foliage is held year-round, with the narrow branchlets ranging from grey-green to dark green. Old cones persist on the branches for several seasons.
Native Range
Native to south-eastern Australia, occurring in Victoria, South Australia, and southern New South Wales. Grows in heath, mallee, and dry sclerophyll woodland on shallow, sandy, gravelly, and rocky soils, often on ridges and stony rises.Suggested Uses
Grown in native gardens, windbreaks, and revegetation on poor and rocky soils, spaced 4-8 feet (1.2-2.5 m) apart. Used as a low screen or hedge and as habitat and seed for native birds. The wiry branchlets and slow growth suit low-water and coastal plantings.How to Identify
Appearance
Size & Dimensions
Height3' - 13'
Width/Spread3' - 8'
Reaches mature size in approximately 5 years
Colors
Bloom Information
Flowers mainly in autumn and winter, March to August, with male plants turning brownish as the pollen-bearing spikes mature and female plants carrying small red flower heads. Wind carries the pollen between separate male and female plants. Woody cones develop over the following months and hold seed for several seasons.
Detailed Descriptions
Flower Description
red (female), brown (male)Foliage Description
grey-green to dark greenGrowing Conditions
Sun Requirements
Requires 6-11 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
Care & Maintenance
Care Guide
Grows in full sun on free-draining sandy, gravelly, or rocky soils and tolerates drought, wind, and poor, low-nutrient ground once established. Watering through the first summer aids establishment, after which little supplementary water is needed. Like other Allocasuarina spp., it hosts nitrogen-fixing bacteria in root nodules and grows without nitrogen feeding. Separate male and female plants are needed for seed to form. Few pests trouble it, and it resprouts from the base after fire in many populations. Growth is slow on shallow soils.Pruning
Light pruning shapes the plant and encourages denser branchlet growth. It tolerates trimming as a low screen or hedge. Plants that resprout from the base can be cut harder to renew old growth.Pruning Schedule
J
F
M
A
M
J
J
A
S
O
N
D
early spring