Common Name: White Alder

General Information

Alnus rhombifolia is a deciduous tree with an open, spreading crown; it can grow from 5 - 35 metres tall with mature trees typically 15 - 24 metres tall. The long, straight bole can be 60 - 90cm in diameter[, , ].
The tree is harvested from the wild for local use asa medicine, food and source of materials.
Alnus rhombifolia is a commonly occurring species in the western United States. There are no known threats that are or will adversely affect it in the foreseeable future. The plant is classified as 'Least Concern' in the IUCN Red List of Threatened Species(2013)[].

Known Hazards

The freshly harvested inner bark is emetic but is alright once it has been dried[].

Botanical References

, ,

Range

Western N. America - Washington to Montana, south to California.

Habitat

Usually found in rocky or gravelly soils along the sides of streams, in canyon bottomlands and gulches, from near sea level to 2400 metres[, ].

Properties

Conservation Status	Least Concern
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Deciduous Tree
Height	12.00 m
Growth Rate	Fast
Pollinators	Wind
Cultivation Status	Wild

Cultivation Details

Prefers a heavy soil and a damp situation[, ]. Grows well in heavy clay soils[]. Tolerates very infertile sites[].
A fairly fast-growing but short-lived species, reaching its maximum size in 50 - 60 years[].
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[].

Edible Uses

Catkins - raw or cooked. A bitter flavour[].

Inner bark[]. No more information is given, but inner bark is often dried and can be used as a flavouring in soups or can be mixed with cereal flours when making bread etc[].

Medicinal

The bark is astringent, diaphoretic, emetic, haemostatic, stomachic and tonic[, ]. A decoction of the dried bark is used in the treatment of diarrhoea, haemorrhages in consumption, stomach aches and to facilitate child birth[].
Externally the bark can be used as a wash for babies with skin diseases, nappy rash etc[].

A poultice of the wood is applied to burns[].

Other Uses

The bark and the strobils are a source of tannin[].

The inner bark can be dried, ground into a powder then mixed with flour and water for use as a dye[]. The colour is not specified[].
The fresh bark can be chewed and used as a red dye[].

The roots have been used to make baskets[].

The heartwood is light brown; the thick band of sapwood is lighter coloured, sometimes nearly white. The grain is straight and close. The wood is light in weight, soft, not strong, brittle, very durable in water[]. It is of limited value as a low-grade lumber[].
The wood is used principally for fuel[].

Propagation

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.