Smooth Alder, Hazel alder
Alnus serrulata

Family: Betulaceae

What it is like

Alnus serrulata is a deciduous Shrub growing to 4.5 m (14ft 9in). See above for USDA hardiness. It is hardy to UK zone 3. 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 cannot grow in the shade. It prefers moist or wet soil.

Height (m): 4.5

Where it is found

Moist lowlands, such as swamps, and along ponds and streams where it forms thickets.

Eastern N. America - Maine to Florida, west to Oklahoma and Indiana.

Conservation Status:

Countries/locations it is found in

How it is used

Food

Rating: 0

Medicine

Rating: 2

A tea made from the bark is analgesic, astringent, blood purifier, diuretic, emetic and purgative. It is used in the treatment of diarrhoea, the pain of childbirth, coughs, toothache and sore mouths. Externally, it is used as an eye wash and a wash for hives, poison ivy rash, piles, swellings and sprains. A decoction of the cones is astringent.

Astringent: Produces contraction in living tissue, reducing the flow of secretions and discharges of blood, mucus, diarrhoea etc.

Diuretic: Acts on the kidneys, promoting the flow of urine.

Emetic: Induces vomiting.

Ophthalmic: Treats eye complaints.

Purgative: A drastic laxative causing a cleansing or watery evacuation of the bowels, usually with a griping pain.

Other

Rating: 2

Trees have extensive root systems and are sometimes planted on the banks of streams in order to prevent erosion. The wood is soft and brittle, weighing 29lb per cubic foot. It is of little commercial value.

Soil stabilization: Plants that can be grown in places such as sand dunes in order to prevent erosion by wind, water or other agents.

Food Forest: Plants for Edible Forest Gardens and Food Forests.

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. Tolerates very infertile sites. Requires a position in full sun, dying out when shaded by taller trees. A fast-growing but short-lived tree. This species is closely related to A. rugosa. 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. For polyculture design as well as the above-ground architecture (form - tree, shrub etc. and size shown above) information on the habit and root pattern is also useful and given here if available. The plant growth habit is multistemmed with multiple stems from the crown. The root pattern is flat with shallow roots forming a plate near the soil surface. The root pattern is suckering with new plants from underground runners away from the plant. 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 Secondary; Bog Garden;

Habit: Shrub

Hardiness: 3-9

Growth:

Soil: Medium, heavy (clay)

Shade: No shade

Moisture: Moist, wet

Things to keep in mind

Its other names

Local names

Synonyms

Betula serrulata.