Casuarina glauca
| Casuarina glauca | |
| Light: |  |
| Moisture: |   |
| Hardiness: | 9 |
| Soil pH: | 5.6-8.4 |
| Evergreen | |
| Height: | 59' |
| Native to: | |
| Nitrogen Fixer | |
| Edible Rating: |  |
| Tea: | Yes |
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Casuarina glauca (common name: swamp oak)
Propagation: Seed - sow late winter to early summer in a greenhouse and only just cover the seed[1]. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in a greenhouse for at least their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts. There are between 700,000 - 970,000 seeds per kilo[2].
Cuttings of half-ripe wood, July/August in a frame[3][4].
Cultivation: Requires a well-drained moisture-retentive soil in full sun[4]. Succeeds in most soils in Australian gardens, including saline ones, and is tolerant of salt spray[3][5][2]. Plants are reported to tolerate high pH, limestone soils, low pH, salt and sand dunes, water-logging, weeds, and wind[2]. Reported to tolerate an annual precipitation in the range of 50 to 400cm, estimated annual temperature range of 18 to 28°C, and a pH of 5 to 8[2]. Plants have grown in Israel under a soil crust of salt (50,000 ppm)[2].
Rarely tolerates temperatures lower than -3°C[2]. Tolerates temperatures down to at least -7°c in Australian gardens[3], and plants are said to tolerate frost in South Africa[2], although this cannot be translated directly to British gardens due to our cooler summers and longer, colder and wetter winters. It might succeed outdoors in the mildest areas of the country.
Spreading by means of root suckers, this species has become a pest in some parts of Florida[2].
Closely related to C. cunninghamiana, though somewhat less hardy[2], it often hybridises in the wild with that species[6]. In fine-textured clays, even in waterlogged soils, C. glauca can develop a deep root system, while C. cunninghamiana and C. equisetifolia develop shallow roots and grow poorly[2].
This species has a symbiotic relationship with certain soil micro-organisms, these form nodules on the roots of the plants and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[3]. Although Nitrogen nodulation is most successful at pH 6 to 8, some natural stands are well nodulated in acid soils (pH ca 4)[2].
Range: Australia - New South Wales, Queensland, Victoria.
Habitat: Usually found in swampy localities[7]. Near salt water estuaries, along sluggish creeks and occasionally on rising ground[6].
Edibility: The needles are chewed to relieve thirst[8]. We assume that this means the leaves[K].
Usage: The plant suckers freely and forms a good windbreak[5]. It has been used to reclaim land, especially eroded mountainsides, and to provide shelterbelts[2]. The plant can spread very freely by means of suckers and has become a noxious weed in some areas - its planting is banned in some parts of Florida[2]. Ditches are sometimes dug on either side of the shelterbelt planting in order to control its spread[2].
Wood - tough. Used for axe handles etc, it is said to be better than hickory (Carya spp) for this purpose[7]. The brownish timber is nicely marked and is used for fencing rails, shingles, salt water pilings, poles, charcoal and fuel[2]. Casuarina spp. have very dense wood, with a specific gravity of 0.8 - 1.2, and a calorific value of ca 5,000 kcal/kg[2]. The wood splits easily, and burns slowly with little smoke or ash[2]. It also can be burned when green, an important advantage in fuel short areas[2]. From their fourth year, trees shed about 4 tons cones/year. These, too, make good pellet-sized fuel (NAS, 1983e)[2].
Soil: Can grow in light, medium, and heavy soils.
Drainage: Prefers well drained soil.
Wind: Tolerates strong winds
In Leaf: Evergreen
Flower Type: Monoecious
Known Hazards: There is a report that the pollen might be allergenic[2].
Links
References
- ↑ Bird, R. Growing from Seed Volume 3. Thompson and Morgan, 1989.
- ↑ 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 2.11 2.12 2.13 2.14 2.15 2.16 2.17 2.18 2.19 Duke, James. Handbook of Energy Crops. 1983.
- ↑ 3.0 3.1 3.2 3.3 Wrigley, John and Murray Fagg. Australian Native Plants. Collins, 1988.
- ↑ 4.0 4.1 Huxley, Anthony. The New Royal Horticultural Society Dictionary of Gardening. MacMillan Press, 1992.
- ↑ 5.0 5.1 Holliday, Ivan and Ron Hill. A Field Guide to Australian Trees. Frederick Muller, 1974.
- ↑ 6.0 6.1 Carolin, R. Flora of the Sydney Region. Reed, 1993.
- ↑ 7.0 7.1 Cribb, Alan. Useful Wild Plants in Australia. William Collins, 1981.
- ↑ Kunkel, Günther. Plants for Human Consumption. Koeltz Scientific Books, 1984.