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Alnus nepalensis D. Don
Betulaceae
Indian Alder, Nepalese Alder
Source: James A. Duke. 1983. Handbook of Energy Crops. unpublished.
- Uses
- Folk Medicine
- Chemistry
- Description
- Germplasm
- Distribution
- Ecology
- Cultivation
- Harvesting
- Yields and Economics
- Energy
- Biotic Factors
- References
Nitrogen-fixing firewood species, the wood of fair quality for use in
unexposed situations. It is used to a limited extent in carpentry and house
construction and for tea boxes. The timber is rather durable, easily sawed,
and seasons well (sp. grav. 0.32–0.37). Locally cultivated by West Java Forest
Service to reforest eroded slopes under everwet climate. A fast growing
species, suitable for plantation cultivation in tropical uplands (Ramoran and
Panot, 1981). The tanniniferous bark is used to deepen the color of Rubia
cordifolia.
The species is cited in the Dictionary of Traditional Chinese Medicine
(from which I borrowed the Illustration) as a useful diuretic to reduce
swelling of the leg.
Bark reported to contain 7% tannin.
Large tree 8–15 (to 30) m tall, to 1 m DBH with thick silver gray bark.
Twigs glabrescent, ribbed, hardly triangular. Leaves alternate, ovate to
oblong, acute or short-acuminate, rounded or cuneate at the base, 7–21 x 4–10
cm; nerves 12–16 pairs, puberulous beneath (glabrescent); vein-axils bearded;
midrib and nerves sulcate and glabrous above; petiole strong, 1.5–2 cm long.
Male catkins to 10 cm by 3–5 mm, in a terminal panicle to 16 cm. Female
inflorescences short, axillary, bearing 3–8 oblong, catkins 10–17 by 6–7 mm.
peduncles 3–6 mm long. Nuts obtrapezoid, emarginate, incl. the wing 2 mm
through, crowned by the style base (van Steenis, 1955–1958).
Reported from the Indonesia-Indochina and Hindustani Center of
Diversity, nepalese alder, or cvs' thereof, is reported to tolerate clay,
flooding, fog, gravel, sand, shade, slope, waterlogging, and weeds. It is not
tolerant of high winds. (2n = 28)
Native to southeast Asia (Burmese hills, Himalayas, Subtropical China,
Indochina). Introduced to Java, India, Hawaii, and the Philippines. I saw a
large tree near Kunming in Yunnan China.
In its native habitat it ranges from 300–3,000 m, in Hawaii from
300–1,800 m, growing well in areas with more than 500 mm annual precipitation.
Van Steenis (1955–1958) suggests it as an afforestation species on eroded
slopes under everwet climatic conditions, growing well between 700–1,800 m.
Grows best in deep well-drained loams or loamy soils of alluvial soils, but
ranges from gravel to sand to clay. I believe it ranges from Subtropical Dry
to Wet Forest Life Zones, with annual rainfall estimated at 5–25 dm, annual
temperature 19–23°C, and pH 6–8.
Seeds may be sown in nurserys for transplants or direct seeded. In
Burma, seed are broadcast during last years of shifting cultivation. It is a
fast grower, even capable of outgrowing sugar ratoon crops. Trees coppice
well, but regrowth seems to be season dependent. In Hawaii, in aseasonal
situations, the trees coppice year round.
In Himachal Pradesh, India, the trees are lopped every other year for
fuel (NAS, 1980a).
Diameters may increase at the rate of ca 2 cm/yr. In Hawaii, 26 year
old trees were 50 cm in diameter.
According to the phytomass files (Duke, 1981b), annual productivity of
other Alnus species ranges from 5 to 26 MT/ha. Although used for
nitrogen fixation, slope stabilization (both of which help the energy budget of
a country), the alder is also used for firewood and might be considered for the
generation of electricity. Heat content of Alnus rubra is about 4,600
kcal/kg atid it, a temperate species, may yield 10–21 m3/ha/yr. The wood
dries rapidly and burns evenly (Little, 1983).
Leaves are sometimes stripped from the tree by coleopterous larvae.
Trunk occasionally attacked by borers.
- Duke, J.A. 1981b. The gene revolution. Paper 1. p. 89–150. In: Office of
Technology Assessment, Background papers for innovative biological technologies
for lesser developed countries. USGPO. Washington.
- Little, E.L. Jr. 1983. Common fuelwood crops: a handbook for their
identification. McClain Printing Co., Parsons, WV.
- N.A.S. 1980a. Firewood crops. Shrub and tree species for energy production.
National Academy of Sciences, Washington, DC.
- Ramoran, E.B. and Panot, I.A. 1981. The potentials of Alnus species. Canopy
International 7(12):8–9.
- Van Steenis, C.G.G.J. 1955–1958. Flora Malesiana. P. Noordhoff Ltd.
Complete list of references for Duke, Handbook of Energy Crops
Last update December 22, 1997