AgroForestryTree Database
Casuarina glauca
 Species identityEcology and distributionPropagation and managementFunctional usesPests and diseasesAdditional InfoBibliographyImages |
Species identity
TaxonomySynonym(s)
Common names
(Creole) : filao, pich pin
(English) : grey buloke, longleaf casuarina, scaly bark beefwood, swamp oak, swamp she oak
(French) : pin d’Australie
(Malay) : ru paya
(Spanish) : pino de Australia
(Trade name) : swamp she-oak
Botanic description
Casuarina glauca is a medium-sized tree 8-20 m high, often with buttressed and fluted stem; rarely a shrub to about 2 m that frequently regenerates through vigorous root suckers. Branchlets spreading or drooping, to 38 cm long. Bark hard, grey or grey-brown, finely fissured and scaly, with a tessellated appearance. Leaves 8-20 mm long and 0.9-1.2 mm in diameter, glabrous; leaf-teeth in whorls of 12-17, rarely 20, erect, 0.6-0.9 mm long. Leaf-teeth on new shoots long and recurved. Male flowers, clusters with pollen along 1.2-4 cm of the tips of some branchlets 7-10 whorls/cm. Rounded female ‘cones’ are 3-12 mm on stalked heads, hairy when young, reddish- to white-pubescent, becoming glabrous, about 6 mm, with dark red stigmas. Mature woody cones subglobose to shortly cylindrical, 9-18 x 7-9 mm, bracteoles broadly acute, opening to release 1 pale, winged nutlet 3.5-5 mm long. Casuarina is from the Malay word ‘kasuari’, which indicates the supposed resemblance of the twigs to the plumage of the cassowary bird. One of the common names of Casuarina species, ‘she-oak’, widely used in Australia, refers to the attractive wood pattern of large lines or rays similar to oak but weaker. The species name is derived from the Greek ‘glaukos’, in reference to the glaucous or bluish-green foliage.
Ecology and distribution
History of cultivationThe swamp she-oak has been extensively planted outside its natural habitat. It was introduced into Cyprus for trial in marshes and saline soils; introduced into Kenya in 1910, and commonly planted outside forest areas; it has been planted successfully in the Nilgiri Hills in the southwest of the Indian Peninsula.
Natural Habitat
C. glauca is one of the most widely planted species of its genus to go out of Australia, especially since it has proved to be superior under Mediterranean type climates and many difficult sites. It grows naturally on estuarine plains flooded with brackish tidal water, and it thrives on dunes at the seaside. It forms pure stands in open forest and woodlands. It tolerates a wide range of conditions such as periodic waterlogging, frost, drought, sea spray, acidity, alkaline or highly saline soils. In fine-textured clays, even in waterlogged soils, it can develop a deep root system. Although hardy to drought and frost, it rarely tolerates temperatures lower than -3 deg. C. The species has the potential to become weedy.
Geographic distribution
Native : Australia
Exotic : China, Cyprus, Dominican Republic, Egypt, Haiti, India, Israel, Kenya, Malawi, Palestine, Puerto Rico, Singapore, South Africa, Thailand, Uganda, United States of America
Biophysical limitsAltitude: 0-900 m, Mean annual temperature: 4-30 deg. C, Mean annual rainfall: 500-4 000 mm Soil type: Although most natural stands are on acidic soils, it has grown well on alkaline clay-loam soils with shallow water tables in hot, semiarid areas. It also does well in pure limestone.
Reproductive Biology
The evidence for wind pollination in casuarinas is persuasive; however, insect pollination is not ruled out. Consists of both male and female trees, that is, it is dioecious (2n = 18).
Propagation and management
Propagation methodsEach cone contains about 70 seeds, with an average germination rate of 60%. Germination is best at a temperature of 20-25 deg. C. In Hawaii, seed is broadcast in spring and covered lightly with less than 1 cm soil. A density of about 200-325 seedlings/square m is recommended, but final densities should be much thinner. Often propagated by potted seedlings. After 12 months, the average height of seedlings from fresh seeds is 52 cm and from stored seed, 70 cm. Successful asexual propagation techniques with casuarinas have been developed in China using water and soil cultures. Homostatic grafting has been done successfully; however, cuttings are difficult to root. To eliminate undesirable root suckers, C. glauca can be grafted onto rootstock of C. equestifolia.Tree Management
Irrigation is required to establish trees in desert areas. Moderately fast growing, and at the age of 7 years, the tree reaches an average height of 5 m with a 72% survival rate. By the age of 12 years, a yield of 295 cubic m/ha of wood and 34 t/ha of green foliage is expected; this is equivalent to 268 tonnes of total dry weight. In Israel, C. glauca outperforms other casuarinas, reaching 20 m in 12-14 years, even on saline water tables. Coppices and produces root suckers vigorously. Inoculation of seedlings with Frankia is recommended when introducing the species to new areas.
Germplasm Management
Seed storage behaviour is orthodox. There is a relative ease of storing seed for long periods under cool conditions. A 50% reduction in viability has been reported after 14-17 years in storage. There is an average of 414 900 seeds/kg.
Functional uses
ProductsFodder: Cattle, goats and sheep will graze C. glauca seedlings, suckers and branchlets. The ground foliage has been used as an ingredient in chicken feed and also has value as a drought fodder. Apiculture: As a source of honey it has no value, and it has only a minor importance as a source of pollen. Fuel: The wood has a calorific value of 4 700 kcal/kg, splits easily, and burns slowly with little smoke or ash. Can also be burned when green, an important advantage in fuel-short areas. Produces excellent charcoal. After 4 years, trees begin to shed about 4 t of cones/year. These, too, make good pellet-sized fuel. The wood is used as firewood in rural areas of Egypt. Fibre: Average fibre length for young trees is 0.97 mm; fibre is used to make a particleboard of adequate strength and stability. Timber: Sapwood is narrow, pale, and resistant to Lyctus borers; the heartwood is brownish with conspicuous rays, hard, tough and fissile, very dense (air-dry 900-980 kg/cubic m, basic density 650-700 kg/cubic m). Used for tool handles, rafters, flooring and turnery. The brownish timber is nicely marked and is used for fencing rails, shingles, and salt-water pilings.Services
Erosion control: The low branching habit and extensive litter production help reduce soil erosion; has been used successfully for dune soil and streambank stabilization. Shade or shelter: C. glauca is an excellent tree for shelter-belts as windbreaks. Reclamation: Has a rapid colonizing ability on disturbed soils, especially in coastal or salt affected situations. Nitrogen fixing: Actively fixes atmospheric nitrogen; greatest when species are inoculated, especially with nodules from the same species. The associated symbiont is Frankia species. Although nitrogen-nodulation is most successful at pH 6-8, some natural stands are well nodulated in acidic soils (about pH 4). Ornamental: Suitable as an ornamental in coastal locations, for example in California. Intercropping: Used for wide-row intercropping. Has been found to increase yields of crops sheltered. To check spread by root suckers, a ditch can be dug between the crop and the shelterbelt, cutting the exposed shoots, or allowing goats and sheep to eat the roots before they become pests.
Pests and diseasesA member of the order Coleoptera, Stromatium fluvum, attacks only C. glauca; the larval galleries occupy the inner bark, the sapwood and the heartwood. The wood-borer makes the stem susceptible to wind damage and rot. Casuarina bacterial wilt (CBW), Pseudomonas solanacearum, is a pathogen that attacks the roots of trees of all ages. In Egypt, serious insect pests of C. glauca are the dry-wood termite, Kalotermes flavicollis, and the coleopteran wood-borers Stromatium fulvum and Macrotema palmata. The larval stage of M. palmata bores into both the sapwood and the heartwood of living trees for many years. Attack by the termites Microtermes michaelseni and Ancistrotermes latinotus has reduced survival of the species to 33% on some sites in Zimbabwe.
Bibliography
Boland DJ. et. al. 1985. Forest trees of Australia. CSIRO. AustraliaDoran CJ, Turnbull JW (eds.). 1997. Australian trees and shrubs: species for land rehabilitation and farm planting in the tropics. ACIAR monograph No. 24, 384 p.
El-Lakany MH, Turnbull JW, Brewbaker JL. 1991. Advances in Casuarina research and utilization. Proceedings of the Second International Casuarina Workshop. Cairo: Desert Development Center, American University.
Faridah Hanum I, van der Maesen LJG (eds.). 1997. Plant Resources of South-East Asia No 11. Auxillary Plants. Backhuys Publishers, Leiden, the Netherlands.
Hong TD, Linington S, Ellis RH. 1996. Seed storage behaviour: a compendium. Handbooks for Genebanks: No. 4. IPGRI.
Katende AB et al. 1995. Useful trees and shrubs for Uganda. Identification, Propagation and Management for Agricultural and Pastoral Communities. Regional Soil Conservation Unit (RSCU), Swedish International Development Authority (SIDA).
NFTA. 1991. Casuarina glauca: A hardy tree with many attributes. NFTA. 91-05. Waimanalo.
Streets RJ. 1962. Exotic forest trees of the British Commonwealth. Claredon Press, Oxford.
Timyan J. 1996. Bwa Yo: important trees of Haiti. South-East Consortium for International Development. Washington D.C.
Webb DB, Wood PJ, Henman GS. 1984. A guide to species selection for tropical and sub-tropical plantations. Tropical Forestry Papers No. 15, 2nd edition. Commonwealth Forestry Institute, Oxford University Press.