Casuarina equisetifolia L.

M. Thulin et al. Flora of Somalia, Vol. 1-4 [updated 2008] https://plants.jstor.org/collection/FLOS

Morphology General Habit

Tree, up to 25 m or more tall, monoecious, with ± drooping branchlets

Morphology Branches

Internodes of deciduous branchlets with 6–8 pubescent furrows

Morphology Leaves

Scale-leaves pale green, in whorls of (6–)7–8, those on deciduous branchlets free for (0.4–)0.5–0.7 mm

Morphology Reproductive morphology Flowers

Male spikes 10–40 mm long and up to c. 2 mm thick, with appressed bracts Female inflorescences 3–5 mm long

Morphology Reproductive morphology Fruits Infructescences

Infructescences shortly cylindric to subglobose, 8–20(–25) x 11–16 mm, the valves pubescent and with 2 longitudinal ridges

Morphology Reproductive morphology Fruits

Fruits pale yellowish-brown, c. 5–7 mm long.

Distribution

S2, 3 native of Australia and probably also SE Asia and the islands of the Pacific, widely planted elsewhere in the tropics and often naturalized.

Ecology

Altitude range c. 5–50 m.

Vernacular

Shawro, showri (Somali).

Bernal, R., G. Galeano, A. Rodríguez, H. Sarmiento y M. Gutiérrez. 2017. Nombres Comunes de las Plantas de Colombia. http://www.biovirtual.unal.edu.co/nombrescomunes/

Vernacular

casuarina, falso pino, pino, pino australiano, pino de Australia, pino extranjero, pino falso australiano

Bernal, R., Gradstein, S.R. & Celis, M. (eds.). 2015. Catálogo de plantas y líquenes de Colombia. Instituto de Ciencias Naturales, Universidad Nacional de Colombia, Bogotá. http://catalogoplantasdecolombia.unal.edu.co

Distribution

Cultivada en Colombia; Alt. 5 - 2650 m.; Andes, Islas Caribeñas, Llanura del Caribe.

Morphology General Habit

Árbol

Casuarinaceae, C.M. Wilmot-Dear. Flora of Tropical East Africa. 1985

Morphology General Habit

Tree 7–25 m. high, monoecious, often pyramidal and much branched; trunks stout (diameter 30 cm., girth up to 1.5 m.), sometimes several from same rootstock.

Morphology General Bark

Bark dark grey or deep brownish, rough or smooth, lenticels usually visible or prominent on younger twigs on which are usually also present white remains of leaf-whorls splitting into longitudinal strips often with quite sharp recurved apices and peeling off with age to leave a ring of transverse scars and cracks at each node.

Morphology Stem

Youngest persistent stems with internodes usually 1.5–2.5 mm., rarely 8 mm. long, and whorls of (6–)7–8 scale-leaves, these straw-coloured and thickly chartaceous, extremely reflexed, free part 2–3 mm. long, 0.4 mm. wide, narrowly triangular with thick excurrent midrib, margin with numerous white or pale cilia often nearly 0.2 mm. long, similar hairs dense or sparse on adaxial surface especially midrib and more sparse on abaxial surface, midrib glabrous.

Morphology Branches

Lower branches stout, spreading, uppermost whippy and ± pendent. Deciduous branchlets arising in abundance from persistent stems especially towards apices, 0.5–0.7 mm. in diameter, bright green with 7–8 slightly paler prominent ribs; scale-leaves in whorls of (6–)7–8, small, adpressed, thinly chartaceous, pale green or straw-coloured, united at base into short tube up to 1 mm. long, free part (0.4–)0.5–0.7 mm. long, (0.2–)0.3 mm. wide, glabrous, margin with cilia similar to but shorter than those on persistent stem-leaves and continuing as a rather inconspicuous fringe of hairs along centre of grooves between stem-ribs.

Morphology Reproductive morphology Inflorescences

Male inflorescences abundant on deciduous branches (rare on persistent branches), 10–30(–40) mm. long, 1.2–2 mm. in diameter (excluding exserted anthers), tapering gradually into short sterile basal region; whorls of bracts 15–22; bracts usually 7 per whorl or less near base, ± adpressed, mucronate, straw-coloured and chartaceous, up to 1.1–1.8 mm. long, 0.4–0.5 mm. wide, glabrous inside, margin and outer surface with hairs as on scale-leaves; bracteoles membranous-scarious, ovate, 0.7–1 × 0.3 mm., apex acute and apical third of margin erose-dentate-ciliate. Perianth of 2 segments up to 0.7 mm. long, 0.4 mm. wide, membranous, rounded. Filaments exserted up to 1.5 mm. from bracts; anthers 0.8–1 mm. long, brownish, mostly maturing and exserted at same time. Female inflorescence axillary towards apices of younger persistent branches, scattered or densely clustered, often on same branches as ♂ and/or mature fruits; heads ± well-defined, ovoid or subglobose, 3–5 mm. long, stalk 3–10 mm.; bracts similar in shape, size, colour and pubescence to those of ♂. Stigmas exserted up to 3–4 mm., red.

sex Male

Male inflorescences abundant on deciduous branches (rare on persistent branches), 10–30(–40) mm. long, 1.2–2 mm. in diameter (excluding exserted anthers), tapering gradually into short sterile basal region; whorls of bracts 15–22; bracts usually 7 per whorl or less near base, ± adpressed, mucronate, straw-coloured and chartaceous, up to 1.1–1.8 mm. long, 0.4–0.5 mm. wide, glabrous inside, margin and outer surface with hairs as on scale-leaves; bracteoles membranous-scarious, ovate, 0.7–1 × 0.3 mm., apex acute and apical third of margin erose-dentate-ciliate. Perianth of 2 segments up to 0.7 mm. long, 0.4 mm. wide, membranous, rounded. Filaments exserted up to 1.5 mm. from bracts; anthers 0.8–1 mm. long, brownish, mostly maturing and exserted at same time.

sex Female

Female inflorescence axillary towards apices of younger persistent branches, scattered or densely clustered, often on same branches as ♂ and/or mature fruits; heads ± well-defined, ovoid or subglobose, 3–5 mm. long, stalk 3–10 mm.; bracts similar in shape, size, colour and pubescence to those of ♂. Stigmas exserted up to 3–4 mm., red.

Morphology Reproductive morphology Fruits Infructescences

Infructescences shortly cylindrical or subglobose with flattened apex, sparse, scattered or densely clustered, 8–17(–25) mm. long, 10–16 mm. in diameter; whorls of paired infructescence-valves (6–)8–9(–12), alternating; valves usually 7–8 per whorl, up to 1.5–3.2 mm. wide, but size and number usually less towards apex; valve-backs with 2 longitudinal ridges and densely red-brown pubescent especially at margins and towards tip, inner surfaces glabrous or pubescent at tip; valves not much thickened, ± obovate, apices acute often mucronate, projecting 1.5–3 mm. above rest of surface, valve-pairs separated from adjacent pairs by gap of 0.5–1 mm.; bracts between valves with free ± acute apex up to 1 mm. long.

Morphology Reproductive morphology Fruits

Samaras varying in size, 5–7 mm. long but those from smaller valves rather smaller; wing usually 3.5–4.5 mm. long, 2–3 mm. wide, whitish or pale brown translucent, longitudinal nerve excurrent into mucronate curved apex; seed-bearing basal part flattened-ovoid, 1.5–2.5 mm. long and wide, up to 1 mm. thick, pale straw-coloured or rarely light brown, glossy but surface not shiny since roughened by minute ± longitudinal patterning of wavy raised lines.

Figures

Figs. 1/3 and 2.

Habitat

Sandy areas above or even on seashore above high tide mark, coastal bushland; also widely planted in similar areas and up to 1500 m.

Distribution

east coast of tropical AfricaMadagascar, Malaysia, Australasia, Polynesiacultivated only: U 2T 5tropical Africa, Mascarene Is., Europe, India, Sri Lanka, N. and S. America K7 P T3 T6 T8 Z

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation

Predicted extinction risk: not threatened. Confidence: confident

Casuarinaceae, C. M. Wilmot-Dear. Flora Zambesiaca 9:6. 1991

Morphology General Habit

Tree 7–25 m. tall, monoecious; sterns stout, up to c. 30 cm. diam. breast height, sometimes several, bark grey-brown.

Morphology Branches

Deciduous branchlets numerous, especially toward the apices of the persistent branches, (0.4)0.5–0.7 mm. in diam., 7–8-ribbed; scale leaves (6)7–8 per whorl, greenish or straw-coloured, free part c. 0.5–0.7 mm. long, appressed, thinly chartaceous, glabrous, margin ciliate. Youngest persistent branches with internodes usually 1.5–2.5 mm. long; scale leaves (6)7–8 per whorl, greenish or straw-coloured, united at base into a short tube c. 1 mm. long, free part 2–3 mm. long, much reflexed, thickly chartaceous, pubescent.

sex Male

Male inflorescences abundant on deciduous branchlets (rare on persistent branches), 10–30(40) x 1.2–2 mm. (width excluding exserted anthers), cylindrical, tapering gradually into a short sterile basal part; whorls of bracts 15–25; bracts c. 7 per whorl, fewer near the base, appressed, 1.1–1.8 x 0.4–0.5 mm., pubescent outside; bracteoles 0.7–1 x 0.3 mm., ovate, acute, erose-dentate-ciliate in upper one-third; perianth segments 2, up to 0.7 x 0.4 mm., rounded, membranous; filaments exserted by 1.5 mm.; anthers 0.8–1 mm. long, brownish.

Morphology Reproductive morphology Inflorescences

Female inflorescences axillary, toward the apices of younger persistent branches, scattered or densely clustered, often on same branches as male inflorescences; heads 3–5 mm. long, ovoid or subglobose; stalk 3–10 mm. long; bracts as for the male inflorescences; stigmas exserted by 3–4 mm., red. Male inflorescences abundant on deciduous branchlets (rare on persistent branches), 10–30(40) x 1.2–2 mm. (width excluding exserted anthers), cylindrical, tapering gradually into a short sterile basal part; whorls of bracts 15–25; bracts c. 7 per whorl, fewer near the base, appressed, 1.1–1.8 x 0.4–0.5 mm., pubescent outside; bracteoles 0.7–1 x 0.3 mm., ovate, acute, erose-dentate-ciliate in upper one-third; perianth segments 2, up to 0.7 x 0.4 mm., rounded, membranous; filaments exserted by 1.5 mm.; anthers 0.8–1 mm. long, brownish.

sex Female

Female inflorescences axillary, toward the apices of younger persistent branches, scattered or densely clustered, often on same branches as male inflorescences; heads 3–5 mm. long, ovoid or subglobose; stalk 3–10 mm. long; bracts as for the male inflorescences; stigmas exserted by 3–4 mm., red.

Morphology Reproductive morphology Fruits Infructescences

Infructescences 8–17(25) x 10–16 mm., shortly cylindrical or subglobose, ± flattened at the apex, (6)8–9(12) whorls of paired infructescence valves; valve pairs 7–8 per whorl, 1.5–3.2 mm. wide (but smaller and fewer towards apex), valves ± obovate, acute to mucronate, apices projecting by 1.5–3 mm., gap between adjacent pairs 0.5–1 mm. wide, valve backs with 2(3) longitudinal ridges (TAB. 35, fig. 3).

Morphology Reproductive morphology Fruits

Samaras pale brown, dull, 5–7 mm. long, to 1 mm. thick; wing 3.5–4.5 x 2–3 mm. (those from small valves smaller), whitish or pale-brown translucent, longitudinal nerve excurrent into a mucronate curved apex.

George R. Proctor (2012). Flora of the Cayman Isands (Second Edition). Royal Botanic Gardens, Kew

Vernacular

AUSTRALIAN PINE, WEEPING WILLOW, BEEFWOOD

Morphology General Habit

A fast-growing tree up to 20 m tall or more, assuming a tall, narrow but open shape resembling a conifer; trunk to 1 m in diameter; branchlets pale or rather dark green, slender (resembling pine-needles), 0.6–0.8 mm thick; scales in whorls of 6–8, 1–3 mm long, acute, ciliate

Morphology Reproductive morphology Flowers

Staminate spikes 1–4 cm long

Morphology Reproductive morphology Fruits

Fruiting heads globose, ca. 1.5 cm in diameter.

Distribution

Grand Cayman, Cayman Brac. Native of Australia, but widely planted and naturalized in most warm countries; common in the West Indies,.

Ecology

Especially in sandy or gravelly soils near the sea, but also flourishing inland.

Note

It is not definitely known when this species was introduced to the Cayman Islands, but this probably occurred during the second half of the nineteenth century. It is now well-established and naturalized in many localities.

IUCN Red List of Threatened Species https://www.iucnredlist.org/species/16728404/16728408

Conservation

LC - least concern

Use

Ornamental tree good for hedging, windbreaks and to stabilise coastal sand, also providing excellent fire wood.

Use

It is often planted and trimmed as a hedge, and is very useful as a windbreak near seashores because of its high tolerance of salt. The wood is very hard, heavy and fine-grained, but unfortunately very susceptible to attack by termites.