Common name: Blue mahoe

Blue Mahoe is a medium-sized timber and landscape tree native to the Caribbean Islands of Jamaica and Cuba, where it occurs mainly in humid tropical forests.

Depending on the growing conditions, it grows at a fast to moderate rate to heights of up to 35 m (115 ft), though it is more typically 15 to 20 m (50 to 65 ft) tall.

The trunk is straight and slender, up to 40 cm (15 in) in diameter and supports a rounded crown of ascending branches. The bark is grey or light brown, smooth on young trees, and becomes fissured with age.

The leaves are large and heart-shaped, 10 to 20 cm (4 to 8 in) long and wide; on top, dark green with veining and occasionally soft hairs; underneath, light green. They remain on the tree year-round and cast deep shade on the ground below.

The flowers are hibiscus-like and large, 8 to 10 cm (3 to 4 in) across, with five orange-yellow or orange-red petals that wither to deep red. They are borne singularly and bloom year-round in constantly humid climates but are short-lived, lasting only a day.

Fertilised flowers are followed by finely hairy, egg-shaped seed capsules 3 to 4 cm (1.2 to 1.6 in) long. Yellow-green when young, they mature to yellow-brown and contain small, finely hairy seeds up to 0.5 cm (0.2 in) long.

Material uses

Timber and lumber- Blue Mahoe produces a medium-weight wood, averaging around 620 kg per cubic metre (39 lb per cubic ft), which classifies it as a durable hardwood suitable for indoor and outdoor construction.

Decay- and rot-resistant wood - The wood also has high natural resistance to rot and decay. The heartwood is grey-blue or grey-green and attractively figured with purple, metallic-blue, and green streaks, resembling highly polished marble.

Furniture and cabinets - Well-formed logs are sawn into planks, prized for furniture and cabinets.

Joinery and millwork - Also suited to joinery and millwork.

Flooring and decking - Made into flooring.

Musical instruments - Crafted into musical instruments.

Wood turning - Turned into turnery items.

Carved craft - Carved into decorative items. Gun stocks are also carved from the wood.

Rope or cordage - The bark stripped from young trees is supple and was traditionally used to make rope, though this practice is now discouraged because it damages the tree.

Environmental uses

Street tree - Blue Mahoe is sometimes planted as a street tree, valued for its shapely form.

Shade tree - Also planted as a shade or landscape tree.

Foliage ornamental - Prized for its eye-catching foliage.

Flowering ornamental - Also valued for its showy flowers.

General interest

Blue Mahoe is highly regarded in Jamaica and has been declared the country's national tree.

Climate

Grows naturally in humid tropical lowland to mid-elevation climates, generally areas with annual lows of 15 to 25°C, annual highs of 25 to 35°C, annual rainfall of 1400 mm to 3800 mm and a dry season of 3 months or less. However, it develops best in areas with annual rainfall of 1600 mm or more.

In Jamaica, Blue Mahoe occurs at elevations from near sea level to 1200 m (4000 ft), where the average low of the warmest month is 16°C (61°F) or above.

Growing

New plants are usually started from seed, harvested by collecting mature seedpods before they open and drying them in the sun until they split. The seed remains viable for four to six months, after which its viability declines.

Sow the seeds in individual containers with a free-draining potting mix, and care for the seedlings in a nursery in shade until they are planted out, when about 40 to 60 cm (1.3 to 2 ft) tall.

Blue Mahoe performs best on fertile, moist, free- to slow-draining clay-loam, silt-loam, loam and sandy-loam soils of an acid to slightly alkaline nature, generally with a pH of 4.5 to 7.5, and on sites with full to partial sun exposure.

Problem features

Blue Mahoe produces many viable seeds which fall to the ground and germinate readily. However, there appears to be no record of it as a serious weed or invasive species anywhere. And this is despite its introduction to many non-native areas as a plantation timber tree.

Books

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

• Barwick, M., et al. 2004, Tropical & subtropical trees : a worldwide encyclopaedic guide, Thames and Hudson, London

• 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

• Chudnoff, M. 1984, Tropical timbers of the world, Forest Service, U.S. Department of Agriculture (USDA), Washington, D.C.

• 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

• Francis, J. K. and Liogier, H. A. 1991, Naturalized exotic tree species in Puerto Rico, General technical report SO-82, USDA Forest Service, Southern Forest Experiment Station, New Orleans

• Francis, J. K. et al. 2000, Silvics of Native and Exotic Trees of Puerto Rico and the Caribbean Islands, Technical Report IITF-15, USDA Forest Service, Rio Piedras, Puerto Rico

• Hill, A. F. 1952, Economic botany : a textbook of useful plants and plant products, 2nd ed, McGraw-Hill, New York

• Little, E. L. & Skolmen, R. G. 1989, Common forest trees of Hawaii (native and introduced), Agricultuural Handbook No. 679, Forest Service, U.S. Department of Agriculture, Washington, D.C.

• 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.

• Longwood, F. R. 1962, Present and potential commercial timbers of the Caribbean: with special reference to the West Indies, the Guianas, and British Honduras, U.S. Dept. of Agriculture Forest Service, Washington, D.C.

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

• Scheffer, T. C & Morrell, J. J. 1998, Natural durability of wood : a worldwide checklist of species, Forest Research Laboratory, Oregon State University, Corvallis, Oregon

• The Garden Section of the Woman's Club of Havana 1958, Flowering plants from Cuban gardens : Plantas floridas de los jardines cubanos, Criterion Books, New York