Common name: Bay rum tree

Bay rum tree is an essential-oil yielding tree originating in the Eastern Caribbean, its natural range extending along the chain of islands from Puerto Rico, through the Virgin Islands and Dominica, to Trinidad and Tobago.

It is a handsome small- to medium-sized tree 5 to 12 m (15 to 40 ft) tall, with an upright trunk and a dense columnar to narrowly rounded crown. The bark is off-white to light brown, smooth and peels to expose pink-white underbark, leaving a mottled surface.

The leaves are oval, glossy dark green on top, dull green underneath, thick and leathery and produce a pleasing spicy aroma when crushed. They remain on the tree in all seasons.

The flowers are small and insignificant, white, fragrant, blooming in loose clusters at the ends of the branches, usually from early spring to summer. They are followed by small green, oblong berries with up to three very small seed inside, ripening to dark purple or near black from late summer to autumn.

Use

The leaves yield on steam distillation an essential oil traded as 'Bay rum oil', a pale yellow to brown-yellow liquid with a dry woody, intensely spicy aroma reminding of Clove (Syzygium aromaticum), Cinnamon (Cinnamon verum) and Nutmeg (Myristica fragrans).

Bay Rum oil has a long history of use in men's fragrance, toiletry and grooming products, such as shaving soap, shampoo, hair tonic and toilet water, which is a weak strength splash-on cologne. Bay rum oil is also used on a limited basis and in small amounts as a flavouring in food, especially ice cream, candy, chewing gum, baked goods, beverages, and medicines.

Harvesting of the leaves begins when the tree is around four to five years old and is repeated every twelve to eighteen months after that, over the life of the tree. Between 10,000 and 20,000 kilograms of leaves can be harvested per hectare, per year, in commercial plantations and with an average oil content of 2.0%, yield 200 to 400 kgs of oil, the equivalent of 178 to 357 pounds per acre. Bay rum is made up of one part bay rum oil blended in one hundred parts rum.

The wood is fine-grained and heavy, averaging around 900 kgs per cubic meter (56 lbs per cubic ft), and has a high natural resistance to decay, making it a durable hardwood. However, the tree is not usually felled for its timber because of its importance as an essential-oil crop. The limbs are sometimes cut for durable poles or posts, including fence-posts and for making into walking sticks. The wood splits easily and makes an excellent, slow-burning firewood or smoke wood for meat and fish.

Bay rum trees are commonly cultivated in gardens in its native range and elsewhere for their handsome form, lush green foliage and the shade they give.

Health use

Bay rum oil contains phenols that have antibiotic and anti-inflammatory properties.

Climate

Grows naturally in moderately humid tropical lowland climates, generally in areas with annual lows of 18 to 25°C, annual highs of 27 to 35°C, annual rainfall of 1000 to 2600 mm and a dry season 5 months or less.

Growing

New plants are usually started from seed and perform best on deep, free-draining, fertile loam soils of a moderately acid to slightly alkaline nature, generally with a pH of 5.5 to 7.5 and on sites with full sun exposure.

Problem features

Birds eat the fruit and disperse the seed. It is listed as a weed in at least one reference publication and is assessed as a high weed risk species for Hawaii by the Hawaii Pacific Weed Risk Assessment (HPWRA) project.

The fruit and essential oil have toxic properties and should not be ingested in their pure and undiluted form.

Books

• Adams, C. D. 1972, Flowering plants of Jamaica, University of the West Indies, Mona, Greater Kingston

• Attokaran, M. 2011, Natural food flavors and colorants, Institute of Food Technologists, Wiley-Blackwell Publishing, Oxfordshire

• 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

• Fawcett, W. 1891, Economic plants, An index to economic products of the vegetable kingdom in Jamaica, Jamaica Government Printing Establishment, Kingston

• Francis, J. K. 1998, Tree species for planting in forest, rural, and urban areas of Puerto Rico, U.S. Department of Agriculture, Forest Service, International Institute of Tropical Forestry, Río Piedras, Puerto Rico

• Jones, M. 2011, The complete guide to creating oils, soaps, creams, and herbal gels for your mind and body : 101 natural body care recipes, Atlantic Publishing Group, Ocala, 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

• Kirk, T. K. 2009, Tropical trees of Florida and the Virgin Islands : a guide to identification, characteristics and uses, 1st ed, Pineapple Press, Sarasota, Florida

• Little, E. L. et al. 1964 and 1974, Common trees of Puerto Rico and the Virgin Islands (2 volumes), Forest Service, U.S. Department of Agriculture (USDA), Washington D.C.

• Macmillan, H. F. 1943, Tropical planting and gardening : with special reference to Ceylon, 5th ed, Macmillan Publishing, London

• McIlroy, R.J. 1963, An introduction to tropical cash crops, Ibadan University Press, Ibadan, Nigeria

• 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

• Randall, R. P. 2007, The introduced flora of Australia and its weed status, Cooperative Research Centre for Australian Weed Management, Glen Osmond, South Australia

• Seidemann, J. 2005, World spice plants: economic usage botany taxonomy, Springer-Verlag, Berlin

• Stewart, A. 2013, The drunken botanist : the plants that create the world's great drinks, 1st ed., Algonquin Books, Chapel Hill, North Carolina

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