Casuarina equisetifolia (Bekele-Tesemma, 2007)
| Casuarina equisetifolia (Bekele-Tesemma, 2007) |
Casuarina equisetifolia Casuarinaceae S.E. Asia, northern and north-eastern Australia
Common names
- English: Whistling pine
- Amargna: Arzelibanos, Shewshewe
Ecology
Occurs naturally on tropical seashores around most coastal areas of the Pacific and Indian oceans, making it the casuarina with the widest distribution. Cultivated and naturalized in Ethiopia, especially in Shoa region, in Dry, Moist, and Wet Kolla and Weyna Dega agroclimatic zones, 0–1,400m. The extensive root system enables the tree to grow in poor soils from 1200-2200m altitude.
Uses
Firewood, charcoal, timber (construction), poles, fodder (young leaves), shade, ornamental, mulch, soil conservation, soil improvement, nitrogen fixation, windbreak, dye, tannin (bark).
Description
A tree to 20 m with “weeping” foliage.
- BARK: Grey‑black cracked with age. LEAVES: Minute scale leaves just visible on the green branchlets, 30 cm long bearing 6-7 leaf scales in each of the whorls, branches hanging down.
- FLOWERS: Pollen‑bearing tips on some branchlets, female flowers in tiny heads with red stigmas.
- FRUIT: Prickly brown, like cones, in clusters, each cone to 2.5 cm long, releasing hundreds of tiny winged seeds.
Propagation
Seedlings. Nursery soil where casuarina are to be raised may need inoculation by addition of soil from beneath mature trees.
Seed
Collect cones at maturity, just before they open to release seed. Then dry cones on a cement floor or plastic sheet so seeds are released. Move around for cones to release seed, then remove cones and collect seed. Seeds prolifically. Good germination rate. 600,000–900,000 seed per kg.
- Treatment: Not necessary.
- Storage: Seed can be stored for at least one year.
Management
Fast growing. Side pruning to get a clear bole. Produces root suckers if roots are exposed. Always add soil from below old trees for root nodule formation.
Remarks
Reputed to be one of the best fuelwood species in the world. The species is said to exhaust soil moisture and lower the water table. It is tolerant to salt water and suppresses undergrowth. Dry branchlets on the ground may become a fire hazard. Termites may damage seedlings as well as young trees. The species is invasive in parts of the world (Reunion, South Africa, Bahamas, Hawaii and Florida). The charcoal produces an intense heat with little smoke or ash.
