Cajaput is an essential oil yield tree originating in Australia and Southeast Asia, it natural range extending from northern Australia to Papua New Guinea, Indonesia, Malaysia, Thailand and Vietnam.
It may reach heights of up to 40 m (120 ft) with a trunk diameter of 1.2 m (4ft), though is more typically a medium-sized tree 10 to 20 m (30 to 60 ft) tall. The trunk is stout and supports a heavily branched crown, which is pyramidal when young, with age becoming rounded. Bark grey-white and peeling off in papery sheets that persist in layers on the trunk.
Leaves elongated oval, up to 10 cm long, tapered at both ends, leathery, dull green and etched with longitudinal lines running from the tip to the stem end. They are alternately arranged along the stems at the ends of the branches and remain on the tree throughout the year.
The flowers have long white filaments and are in dense clusters resembling bottle brushes. These bloom on and off throughout the year but are at their fullest around autumn and are followed by small, woody, cup-shaped seed capsules up to 0.4 cm (0.2 in) in diameter enclosing many tiny seed.
The fresh leaves and young stems yield on steam distillation about 0.9 to 1% of a pale yellow essential oil traded as 'Cajeput oil'. It is mostly comprised of Cineole (also know as Eucalyptole), which is strongly antiseptic and also the principal compound found in Eucalyptus oil.
Cajeput oil has a camphor-like odour and has long been used medicinally in its native range, internally as a treatment against coughs and colds and externally for relieving pain. This mirrors its use in western medicine as an antiseptic, principally against colds, sore throat, respiratory infections and laryngitis. Similar to Eucalyptus oil in application, it is often steam inhaled. It is also useful against infections of the genito-urinary system and against roundworms.
Applied externally it acts as a counterirritant, helping to stimulate circulation and because of this, is found as an active ingredient in branded ointments, gels and liniments.
Among the many everyday products containing Cajeput oil as an ingredient are toothpaste, lip balms, mouthwashes, gargles, throat lozenges, deodorants, shampoos, acne products, sunscreens, as well as dentistry and veterinary products. It is also commonly found as a fragrance component in soaps, lotions and perfumes and here its camphor odour is very similar to Niaouli oil from Broadleaf paperbark (Melaleuca quinquenervia).
Cajeput oil in very small amounts is also used as a flavouring in non-alcoholic beverages, confectionery, frozen desserts, baked goods, condiments and relishes.
The trunk yields a medium-weight wood, in the 700 to 800 kgs per cubic meter (44 to 50 lbs per cubic ft) range, with good natural resistance to rot, decay and wood boring insects, and is as well durable in contact with fresh and salt water.
The heartwood is pale brown and fine-grained. Well-formed logs, when available, are sawn into beams used for bridge and wharf construction, or into planks for flooring, furniture and cabinets, as well as boxes and crates. It also makes an excellent firewood.
The soft, papery bark has promise as a source for fibreboard, paper and packing material, and as cork substitute in insulation. It can be easily torn off the tree by hand and has long been used as kindling for starting fires.
Honeybees are observed actively working the flowers but there does not appear to be much information on its value to honey production.
It is sometimes cultivated as a flowering ornamental and as a street tree in parts of its native range.
The name Cajaput is from the Malayan Caju puti which means white tree, referring to the tree's grey-white bark.
Grows naturally in humid tropical lowland climates, generally in frost-free areas with annual lows of 19 to 25 °C, annual highs of 29 to 35 °C, annual rainfall of 900 to 4000 mm and a dry season of 5 months or less. It occurs on low, swampy coastal plains and where there is seasonal flooding, as well in hilly terrain on dry, rocky and infertile soils.
New plants are usually started from seed and the seedlings tended in a nursery until the formation of the first flower buds, at around two years old, at which time they are planted out in the field. New plants can also be started from stem and branch cuttings.
Performs best on free- and slow-draining clay, loam and sand soils of an acid to neutral nature, generally with a pH of 4.5 to 7.0 and on sites with full to partial sun exposure. It has good tolerance to seasonal flooding, waterlogged soils, soil salt and strong wind conditions. Varieties coming from eastern Indonesia are reportedly adapted to growing in hilly inland areas on infertile, gravelly soil.
In commercial operations, harvesting starts at four years after transplanting and is usually mechanical, stripping the leaves and stems and cutting the plant back to about 1 m (3 ft) tall. Harvesting is then repeated at yearly intervals over a period of about five years, after which a replanting is done.
Harvests of fresh leaves in commercial operations average 7,500 kgs per hectare per year and on steam distillation yield about 65 kgs of oil, the equivalent of 58 lbs of oil per acre per year.
The seed that fall to the ground are easily dispersed by flowing water and germinate readily. It can form dense stands, particularly in swampy areas or low-lying land subject to seasonal flooding.
The essential oil is poisonous if ingested in large amounts and should only be taken internally under medical supervision.
Arctander, S. 1960, Perfume and flavor materials of natural origin, Elizabeth, New Jersey
Brady, G. S. & Clauser, H. R & Vaccari, J. A. 2002, Materials handbook : an encyclopedia for managers, technical professionals, purchasing and production managers, technicians and supervisors, 15th ed., McGraw-Hill, New York
C.A.B. International 2013, The CABI encyclopedia of forest trees, CABI Publishing, Wallingford, Oxfordshire
Chevallier, A. 2000, Encyclopedia of herbal medicine, 2nd American ed., Dorling Kindersley, New York
Culbreth, D. M. R. 1927, A manual of materia medica and pharmacology : comprising the organic and inorganic drugs which are or have been recognized by the United States pharmacopœia, 7th ed., Febiger, Philadelphia
Do, D. S. & Nguyen, H. N. 2003, Use of indigenous tree species in reforestation in Vietnam, Agricultural Publishing House, Hanoi
Doran, J. C & Turnbull, J. W. 1997, Australian trees and shrubs : species for land rehabilitation and farm planting in the tropics, 2nd ed, Australian Centre for International Agricultural Research (ACIAR), Canberra, Australian Capital Territory
Groom, N. 1997, The new perfume handbook, 2nd ed., Blackie Academic & Professional, London
Jelks, Mary 1986, Allergy plants : that cause sneezing and wheezing, 1st ed., World-Wide Publications, Tampa, Florida
Khan, I. A. & Abourashed, E. A. 2010, Leung's encyclopedia of common natural ingredients : used in food, drugs and cosmetics, 3rd edition, Wiley Publishing, Hoboken, New Jersey
Macmillan, H. F. 1943, Tropical planting and gardening : with special reference to Ceylon, 5th ed, Macmillan Publishing, London
National Research Council (Board on Science and Technology for International Development) 1983, Firewood crops : shrub and tree species for energy production (Volume 2), The National Academies Press, Washington D. C.
Oyen, L. P. A. & Nguyen X. D. 1999, Plant Resources of South-East Asia (PROSEA) 19 : Essential-oil plants, Backhuys Publishers, Leiden
Randall, R. P. 2002, A global compendium of weeds, R.G. and F.J. Richardson Press, Melbourne
Weiss, E. A. 1997, Essential oil crops, CABI Publishing, Wallingford, Oxfordshire
Winter, R. 2009, A consumer's dictionary of cosmetic ingredients : complete information about the harmful and desirable ingredients found in cosmetics and cosmeceuticals, 7th ed, Three Rivers Press, New York
This website is provided for general information only. Iplantz makes no statements, representations or warranties as to the accuracy or completeness of the content of this website and does not accept any liability to you or any other person for the information which is provided or referred to on this website.
In particular, Iplantz does not represent or warrant that any dataset or the data it contains is accurate, authentic or complete, or suitable for your needs. Changes in circumstances after the time of publication may impact the accuracy of datasets and their contents.
To the maximum extent permitted by law, Iplantz accepts no liability whatsoever to any person arising from or connected with the use of or reliance on any information or advice provided on this website or incorporated into it by reference, including any dataset or data it contains. No responsibility is taken for any information or services that may appear on any linked websites.