Alnus firma ("Yashabushi")

Japanese name: ヤシャブシ （夜叉五倍子）
Scientific name: Alnus firma

[Overview]
A large deciduous shrub or small tree 10–15 m tall, found in sunny landslide areas and riverbeds in the mountains.
It branches well and has a crown that spreads sideways in the upper part.
The bark is grayish brown and cracks and peels irregularly.
Young branches are slightly hairy.
Leaves are simple and alternate, narrowly ovate to ovate-lanceolate, 4–10 cm long and 2–4.5 cm wide, and almost hairless.
There are 13–17 pairs of parallel lateral veins.
The leaf margins have fine double serration.
There are male and female flowers, which bloom before the leaves unfold.
The male flowers grow on cylindrical catkins 4–6 cm long, hanging down singly from the branch tips or from the leaf axils in the upper part of the branches.
The male catkins have no stalk.
The male flowers are small and borne in threes beside scale-like bracts; the perianth is 4-lobed and there are 4 stamens.
The female flowers grow on erect, cone-like inflorescences, one or two at a time, at the branch tips or in the leaf axils below the male catkins.
The female inflorescences have stalks.
The female flowers have no perianth.
The fruiting spike is broadly elliptical and cone-like, 1.5–2 cm long, with the fruits attached to the inner surface of the scales.
The fruit is a flattened nut with wings on both sides, and the style remains at the tip.

[Uses]
The fruiting spikes are used medicinally and also as a mordant.

[Cultivation]
Propagate from seed or by cuttings.
Thanks to symbiotic microbes, it grows well even in poor soil.
Plant it in a sunny place.
There are no particular pests or diseases.

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