Nepalese Alder
Alnus nepalensis
Family: Betulaceae
What it is like
Alnus nepalensis is a deciduous Tree growing to 22 m (72ft 2in) at a fast rate. See above for USDA hardiness. It is hardy to UK zone 9. It is in flower from September to October. The species is monoecious (individual flowers are either male or female, but both sexes can be found on the same plant) and is pollinated by Wind. It can fix Nitrogen. Suitable for: medium (loamy) and heavy (clay) soils and can grow in heavy clay and nutritionally poor soils. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist or wet soil.
Height (m): 22
Where it is found
Forests in ravines, on stream banks and occasionally in drier localities, 900 - 2700 metres in the Himalayas.
E. Asia - China, Himalayas
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 0
Medicine
Rating: 1
A useful diuretic for reducing swelling of the leg. The juice of the bark is boiled and the gelatinous liquid applied to burns.
Diuretic: Acts on the kidneys, promoting the flow of urine.
Other
Rating:
The bark contains 7% tannin, it is used in dyeing and tanning. It is used to deepen the red colour of madder, Rubia cordifolia. A fast growing species, it is suitable for plantation cultivation in tropical uplands. The tree is locally cultivated by West Java Forest Service to reforest eroded slopes under ever-wet climates. The tree establishes rapidly on areas subject to landslides, binding the soil with its extensive root system and stabilizig the slope. Wood - soft, tough, even grained, rather durable, easily sawn, seasons well and does not warp. It is used to a limited extent in carpentry, house construction, tea boxes, for making furniture, rope bridges etc. A very good timber, it deserves to be more widely used. In India the trees are coppiced every two years for fuel.
Dye: Plants that provide dyes.
Fodder: Food given to the animals (including plants cut and carried to them) rather than forage for themselves.
Fuel: Usually wood, plant materials that have been mentioned as being a good fuel.
Soil stabilization: Plants that can be grown in places such as sand dunes in order to prevent erosion by wind, water or other agents.
Wood: A list of the trees and shrubs that are noted for having useful wood.
Agroforestry Services: Crop shade: Plants providing crop shade especially trees.
Agroforestry Services: Nitrogen: Plants that contribute to nitrogen fixation include the legume family – Fabaceae.
Fodder: Bank: Fodder banks are plantings of high-quality fodder species. Their goal is to maintain healthy productive animals. They can be utilized all year, but are designed to bridge the forage scarcity of annual dry seasons. Fodder bank plants are usually trees or shrubs, and often legumes. The relatively deep roots of these woody perennials allow them to reach soil nutrients and moisture not available to grasses and herbaceous plants.
Management: Coppice: Cut to the ground repeatedly - resprouting vigorously. Non-destructive management systems maintaining the soil organic carbon.
Management: Standard: Plants grow to their standard height. Harvest fruit, seeds, or other products. Non-Destructive management systems.
Regional Crop: These crops have been domesticated and cultivated regionally but have not been adopted elsewhere and are typically not traded globally, Examples in this broad category include perennial cottons and many nuts and staple fruits.
Agroforestry Services: Crop shade: Plants providing crop shade especially trees.
Agroforestry Services: Nitrogen: Plants that contribute to nitrogen fixation include the legume family – Fabaceae.
Fodder: Bank: Fodder banks are plantings of high-quality fodder species. Their goal is to maintain healthy productive animals. They can be utilized all year, but are designed to bridge the forage scarcity of annual dry seasons. Fodder bank plants are usually trees or shrubs, and often legumes. The relatively deep roots of these woody perennials allow them to reach soil nutrients and moisture not available to grasses and herbaceous plants.
Management: Coppice: Cut to the ground repeatedly - resprouting vigorously. Non-destructive management systems maintaining the soil organic carbon.
Management: Standard: Plants grow to their standard height. Harvest fruit, seeds, or other products. Non-Destructive management systems.
Regional Crop: These crops have been domesticated and cultivated regionally but have not been adopted elsewhere and are typically not traded globally, Examples in this broad category include perennial cottons and many nuts and staple fruits.
Carbon Farming: Plants that can be a critical part of the solution to climate problems. The Carbon Farming Solution - Eric Toensmeier.
Nitrogen Fixer: Plants that fix nitrogen in the soil
How it is grown
Prefers a heavy soil and a damp situation. Grows well in heavy clay soils. Succeeds in very infertile sites. The Nepalese alder is reported to tolerate clay, flooding, fog, gravel, sand, shade, slope, water-logging, and weeds. It is not tolerant of high winds. Grows best in deep well-drained loams or loamy soils of alluvial soils, but ranges from gravel to sand to clay. Prefers an annual rainfall estimated at 50 - 250cm, an annual average temperature in the range of 19 - 23°C, and a pH of 6 - 8. This species is possibly only hardy in the milder areas of Britain. 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. In garden design, as well as the above-ground architecture of a plant, root structure considerations help in choosing plants that work together for their optimal soil requirements including nutrients and water. The root pattern is branching: a heart root, dividing from the crown into several primary roots going down and out .
Propagating it: Seed - best sown in a cold frame as soon as it is ripe and only just covered. Spring sown seed should also germinate successfully so long as it is not covered. The seed should germinate in the spring as the weather warms up. When large enough to handle, prick the seedlings out into individual pots. If growth is sufficient, it is possible to plant them out into their permanent positions in the summer, otherwise keep them in pots outdoors and plant them out in the spring. If you have sufficient quantity of seed, it can be sown thinly in an outdoor seed bed in the spring. The seedlings can either be planted out into their permanent positions in the autumn/winter, or they can be allowed to grow on in the seed bed for a further season before planting them. Cuttings of mature wood, taken as soon as the leaves fall in autumn, outdoors in sandy soil.
Best place to grow: Woodland Garden Canopy; Bog Garden;
Habit: Tree
Hardiness: 8-11
Growth: Fast
Soil: Medium, heavy (clay)
Shade: Semi-shade, no shade
Moisture: Moist, wet