Common name: Cinnamon Myrtle

Cinnamon Myrtle is an ornamental, essential-oil-yielding tree native to Australia, with a natural range along the east coast, from Bermagui in southern New South Wales to Fraser Island in central Queensland.

It is a small- to medium-sized tree that reaches up to 12 m (40 ft) in its natural habitat, though it is typically 5 to 10 m (16 to 32 ft) tall, with a stout trunk supporting a densely branched, rounded crown. The bark is pale brown, vertically fissured and becoming scaly with age.

Leaves are oval to elliptical, 4 to 7 cm (1.6 to 2.7 in) long and tapering to a fine point. On top, they are dark, glossy green beneath pale green and arranged in pairs at the ends of the branches. They remain on the tree year-round and give off a spicy, cinnamon-like aroma when crushed.

Flowers are small, creamy white, with long white stamens, and bloom in summer in profuse clusters that almost hide the green foliage from view. Fertilised flowers develop into small, brown, star-shaped seed capsules with tiny seeds inside. The seeds are released when the capsules fall to the ground and split open.

Royal Botanic Gardens Victoria, Melbourne, Australia

Material uses

Essential oil - Four varieties, or forms, of Cinnamon myrtle are known; each yields a distinct essential oil from its leaves, extracted by steam distillation. The four forms, Elemicin, Isoelemicin, Methyleugenol and Isoeugenol, are named after the chemical constituent that predominates in the oil. Essential-oil yields range from 0.5 to 2.2% of the fresh leaves by weight, depending on the variety or form, growing conditions and the proportion of new to old-growth in the distilled material.

Natural fragrance - Methyleugenol and Isoeugenol are well-known and commonly used perfume materials. Similarly, when isolated, Elemicin and Isoelemicin are used as modifiers and fixatives in perfume blends to extend fragrance longevity. Elemicin is also the main constituent of Elemi oil, derived from the resin of the Elemi tree (Canarium luzonicum) and is a constituent of Nutmeg (Myristica fragrans).​

Natural insect repellent - When crushed, the leaves can be rubbed on the skin as a natural insect repellent.

Hardwood - The wood is hard, tough, close-grained, and heavy, averaging around 1050 kg per cubic meter (66 lb per cubic ft). When sawn and seasoned, it develops an attractive pinkish-grey colour. However, the logs come in diameters too small to make sawing them into lumber practical.

Tool handles - Instead, the wood is crafted into handles for axes and other tools.

Edible uses

Natural flavouring - The leaves are also used to flavour desserts, confectionery, herbal teas, and locally produced gins in Australia.

Health uses

Natural digestive aid - A leaf infusion is used in herbal medicine as a carminative to relieve flatulence or intestinal gas.

Climate

Grows naturally in warm temperate and subtropical rainforest climates, generally best in areas with annual lows of 9 to 17°C, annual highs of 19 to 29°C, annual rainfall of 700 to 2500 mm and a dry season of 3 months or less.

Growing

New plants are usually started from semi-hardwood cuttings. It performs best in rich, moist, free-draining soil that is mildly acid to neutral, generally with a pH of 5.5 to 7.0, and in sites with partial sun exposure. It has poor tolerance to alkaline, slow-draining or waterlogged soils.

Problem features

None know.

Books

• Arctander, S. 1960, Perfume and flavor materials of natural origin, Elizabeth, New Jersey

• Boland, D. & Brooker, I. & McDonald, M. W. 2006, Forest trees of Australia, 5th ed., CSIRO Publishing (Ensis), Melbourne

• Cribb, A. B. & Cribb, J. W. 1982, Useful wild plants in Australia, William Collins, Sydney

• Floyd, A. G. 1979, N.S.W. rainforest trees, 2nd. ed., Forestry Commission of NSW, Sydney, Australia

• Weiss, E. A 2002, Spice crops, CABI Publishing, Wallingford, United Kingdom

Articles, Journals, Reports and Working Papers

• Hegarty, M. P. & Hegarty, E. E. & Wills, R. B. H. 2001, Food safety of Australian Plant Bushfoods, Centre for Advancement of Food Technology & Nutrition, University of Newcastle, Rural Industries Research and Development Corporation (RIRDC), Australian Capital Territory